diff --git a/app/api/generate/media-prompt/route.ts b/app/api/generate/media-prompt/route.ts
new file mode 100644
index 000000000..bc8b03e5a
--- /dev/null
+++ b/app/api/generate/media-prompt/route.ts
@@ -0,0 +1,59 @@
+/**
+ * Auto-generates a media generation prompt from a slide indication text.
+ * Used when the user picks a media type not present in the original slide.
+ */
+import { NextRequest } from 'next/server';
+import { createLogger } from '@/lib/logger';
+import { apiError, apiSuccess } from '@/lib/server/api-response';
+import { callLLM } from '@/lib/ai/llm';
+import { resolveModelFromHeaders } from '@/lib/server/resolve-model';
+
+const log = createLogger('MediaPrompt API');
+
+export const maxDuration = 30;
+
+export async function POST(req: NextRequest) {
+  try {
+    const body = await req.json();
+    const { indicationText, mediaType, language } = body as {
+      indicationText: string;
+      mediaType: 'image' | 'video';
+      language?: string;
+    };
+
+    if (!indicationText || !indicationText.trim()) {
+      return apiError('MISSING_REQUIRED_FIELD', 400, 'indicationText is required');
+    }
+    if (!mediaType) {
+      return apiError('MISSING_REQUIRED_FIELD', 400, 'mediaType is required');
+    }
+    if (mediaType !== 'image' && mediaType !== 'video') {
+      return apiError('INVALID_REQUEST', 400, 'mediaType must be "image" or "video"');
+    }
+
+    const { model: languageModel } = await resolveModelFromHeaders(req);
+
+    const mediaLabel = mediaType === 'image' ? 'image' : 'short video loop';
+    const langHint = language ? ` The course language is ${language}.` : '';
+
+    const result = await callLLM(
+      {
+        model: languageModel,
+        system: `You are a visual media prompt writer. Given a slide description, write a concise prompt (1–2 sentences, max 30 words) for generating a ${mediaLabel} that visually represents the slide content. Respond with ONLY the prompt text — no quotes, no explanation.${langHint}`,
+        prompt: indicationText,
+        maxOutputTokens: 150,
+      },
+      'media-prompt',
+    );
+
+    const prompt = result.text.trim();
+    log.info(
+      `Generated media prompt for ${mediaType}: "${prompt.length > 60 ? prompt.slice(0, 60) + '...' : prompt}"`,
+    );
+
+    return apiSuccess({ data: { prompt } });
+  } catch (error) {
+    log.error('media-prompt generation failed:', error);
+    return apiError('INTERNAL_ERROR', 500, error instanceof Error ? error.message : String(error));
+  }
+}
diff --git a/app/api/generate/narration-text/route.ts b/app/api/generate/narration-text/route.ts
new file mode 100644
index 000000000..b43d53394
--- /dev/null
+++ b/app/api/generate/narration-text/route.ts
@@ -0,0 +1,54 @@
+/**
+ * Generates narration text for a slide from its indication (description + key points).
+ * Used by the "Regenerate narration" AI button in the slide regeneration dialog.
+ */
+import { NextRequest } from 'next/server';
+import { createLogger } from '@/lib/logger';
+import { apiError, apiSuccess, requireAuth } from '@/lib/server/api-response';
+import { callLLM } from '@/lib/ai/llm';
+import { resolveModelFromHeaders } from '@/lib/server/resolve-model';
+
+const log = createLogger('NarrationText API');
+
+export const maxDuration = 30;
+
+export async function POST(req: NextRequest) {
+  const user = await requireAuth(req);
+  if ('status' in user && user instanceof Response) return user;
+
+  try {
+    const body = await req.json();
+    const { indicationText, language } = body as {
+      indicationText: string;
+      language?: string;
+    };
+
+    if (!indicationText || !indicationText.trim()) {
+      return apiError('MISSING_REQUIRED_FIELD', 400, 'indicationText is required');
+    }
+
+    const { model: languageModel } = await resolveModelFromHeaders(req);
+
+    const langHint = language
+      ? ` The narration MUST be written in ${language} (match the language of the key points).`
+      : '';
+
+    const result = await callLLM(
+      {
+        model: languageModel,
+        system: `You are an expert educational narrator. Given a slide's description and key points, write a natural spoken narration for a teacher to deliver while presenting the slide. The narration should:\n- Be conversational and engaging, as if speaking directly to students\n- Cover the key points clearly without reading them verbatim\n- Be 2-4 sentences long (suitable for a 15-30 second voiceover)\n- NOT include stage directions, quotes, or explanations — only the spoken text itself${langHint}`,
+        prompt: indicationText,
+        maxOutputTokens: 300,
+      },
+      'narration-text',
+    );
+
+    const text = result.text.trim();
+    log.info(`Generated narration text (${text.length} chars)`);
+
+    return apiSuccess({ data: { text } });
+  } catch (error) {
+    log.error('narration-text generation failed:', error);
+    return apiError('INTERNAL_ERROR', 500, error instanceof Error ? error.message : String(error));
+  }
+}
diff --git a/app/api/generate/scene-content-only/route.ts b/app/api/generate/scene-content-only/route.ts
new file mode 100644
index 000000000..34d9049ce
--- /dev/null
+++ b/app/api/generate/scene-content-only/route.ts
@@ -0,0 +1,83 @@
+/**
+ * Synchronous slide content generation — returns raw PPTElements without persisting a scene.
+ * Used by the per-slide regeneration flow.
+ */
+import { NextRequest } from 'next/server';
+import { createLogger } from '@/lib/logger';
+import { apiError, apiSuccess } from '@/lib/server/api-response';
+import { generateSceneContentFromInput } from '@/lib/server/scene-content-generation';
+import { getStorageBackend } from '@/lib/server/storage';
+import { resolveModelFromHeaders } from '@/lib/server/resolve-model';
+import type { SceneOutline, GeneratedSlideContent } from '@/lib/types/generation';
+import type { AgentInfo } from '@/lib/generation/generation-pipeline';
+
+const log = createLogger('SceneContentOnly API');
+
+export const maxDuration = 60;
+
+export async function POST(req: NextRequest) {
+  try {
+    const body = await req.json();
+    const { outline, stageId, agents, themeId } = body as {
+      outline: SceneOutline;
+      stageId: string;
+      agents?: AgentInfo[];
+      themeId?: string;
+    };
+
+    if (!outline) {
+      return apiError('MISSING_REQUIRED_FIELD', 400, 'outline is required');
+    }
+    if (!stageId) {
+      return apiError('MISSING_REQUIRED_FIELD', 400, 'stageId is required');
+    }
+
+    if (outline.type !== 'slide') {
+      return apiError('INVALID_REQUEST', 400, 'Only slide-type outlines are supported');
+    }
+
+    // Load stage metadata and outlines from server storage
+    const backend = getStorageBackend();
+    const [stageData, savedOutlines] = await Promise.all([
+      backend.loadStage(stageId),
+      backend.loadOutlines(stageId),
+    ]);
+
+    if (!stageData) {
+      return apiError('NOT_FOUND', 404, 'Stage not found');
+    }
+
+    const allOutlines = savedOutlines ?? [outline];
+    const stageInfo = {
+      name: stageData.stage.name ?? '',
+      description: stageData.stage.description,
+      language: stageData.stage.language,
+      style: stageData.stage.style,
+      themeId,
+    };
+
+    // ── Model resolution from request headers ──
+    const { modelString } = await resolveModelFromHeaders(req);
+
+    const result = await generateSceneContentFromInput({
+      outline,
+      allOutlines,
+      stageId,
+      stageInfo,
+      agents,
+      modelConfig: { modelString },
+    });
+
+    // Return only the slide content fields (elements + background)
+    const slideContent = result.content as GeneratedSlideContent;
+    return apiSuccess({
+      data: {
+        elements: slideContent.elements ?? [],
+        background: slideContent.background,
+      },
+    });
+  } catch (error) {
+    log.error('scene-content-only failed:', error);
+    return apiError('INTERNAL_ERROR', 500, error instanceof Error ? error.message : String(error));
+  }
+}
diff --git a/components/classroom/regenerate-slide-dialog.tsx b/components/classroom/regenerate-slide-dialog.tsx
new file mode 100644
index 000000000..886a82724
--- /dev/null
+++ b/components/classroom/regenerate-slide-dialog.tsx
@@ -0,0 +1,535 @@
+'use client';
+
+import { useState, useEffect, useCallback, useRef } from 'react';
+import { Sparkles } from 'lucide-react';
+import {
+  Dialog,
+  DialogContent,
+  DialogDescription,
+  DialogHeader,
+  DialogTitle,
+  DialogFooter,
+} from '@/components/ui/dialog';
+import { Button } from '@/components/ui/button';
+import { Textarea } from '@/components/ui/textarea';
+import { Input } from '@/components/ui/input';
+import { Label } from '@/components/ui/label';
+import { Switch } from '@/components/ui/switch';
+import {
+  Select,
+  SelectContent,
+  SelectItem,
+  SelectTrigger,
+  SelectValue,
+} from '@/components/ui/select';
+import { useSettingsStore } from '@/lib/store/settings';
+import type { ThemeListItem } from '@/lib/types/theme';
+import { useI18n } from '@/lib/hooks/use-i18n';
+import { outlineToIndication, indicationToOutline } from '@/lib/hooks/use-scene-regenerator';
+import { getCurrentModelConfig } from '@/lib/utils/model-config';
+import { CompactModelSelector } from '@/components/generation/model-selector-popover';
+import { MediaPopover } from '@/components/generation/media-popover';
+import type { Scene } from '@/lib/types/stage';
+import type { SceneOutline } from '@/lib/types/generation';
+import type { SpeechAction } from '@/lib/types/action';
+import type { RegenerateParams } from '@/lib/hooks/use-scene-regenerator';
+
+export interface RegenerateFormValues {
+  title: string;
+  indication: string;
+  regenerateSlide: boolean;
+  audioText: string;
+  modifyAudio: boolean;
+  mediaType: 'none' | 'image' | 'video' | 'keep';
+  mediaPrompt: string;
+  themeId: string;
+}
+
+interface RegenerateSlideDialogProps {
+  open: boolean;
+  scene: Scene;
+  outline: SceneOutline;
+  initialValues?: RegenerateFormValues;
+  /** Error message from the last regeneration attempt, if any */
+  errorMessage?: string;
+  onRegenerate: (params: RegenerateParams) => void;
+  onClose: () => void;
+}
+
+function sceneToAudioText(scene: Scene): string {
+  return (scene.actions ?? [])
+    .filter((a): a is SpeechAction => a.type === 'speech')
+    .map((a) => a.text)
+    .join('\n\n');
+}
+
+function outlineToMediaType(outline: SceneOutline): 'none' | 'image' | 'video' | 'keep' {
+  const generations = outline.mediaGenerations ?? [];
+  // If the outline had media, default to 'keep' so it's preserved without re-generation
+  if (generations.some((g) => g.type === 'video')) return 'keep';
+  if (generations.some((g) => g.type === 'image')) return 'keep';
+  return 'none';
+}
+
+function outlineToMediaPrompt(
+  outline: SceneOutline,
+  mediaType: 'none' | 'image' | 'video',
+): string {
+  if (mediaType === 'none') return '';
+  const entry = (outline.mediaGenerations ?? []).find((g) => g.type === mediaType);
+  return entry?.prompt ?? '';
+}
+
+export function RegenerateSlideDialog({
+  open,
+  scene,
+  outline,
+  initialValues,
+  errorMessage,
+  onRegenerate,
+  onClose,
+}: RegenerateSlideDialogProps) {
+  const { t } = useI18n();
+  const defaultThemeId = useSettingsStore((s) => s.themeId);
+
+  const [title, setTitle] = useState('');
+  const [regenerateSlide, setRegenerateSlide] = useState(true);
+  const [indication, setIndication] = useState('');
+  const [audioText, setAudioText] = useState('');
+  const [modifyAudio, setModifyAudio] = useState(false);
+  const [mediaType, setMediaType] = useState<'none' | 'image' | 'video' | 'keep'>('none');
+  const [mediaPrompt, setMediaPrompt] = useState('');
+  const [themeId, setThemeId] = useState(defaultThemeId);
+  const [themes, setThemes] = useState<ThemeListItem[]>([]);
+  const [isGeneratingPrompt, setIsGeneratingPrompt] = useState(false);
+  const [isGeneratingNarration, setIsGeneratingNarration] = useState(false);
+  const [narrationError, setNarrationError] = useState<string | null>(null);
+  const [promptError, setPromptError] = useState<string | null>(null);
+  const promptAbortRef = useRef<AbortController | null>(null);
+  const narrationAbortRef = useRef<AbortController | null>(null);
+
+  // Initialise form values on open + fetch theme list
+  useEffect(() => {
+    if (!open) return;
+    if (initialValues) {
+      setTitle(initialValues.title);
+      setRegenerateSlide(initialValues.regenerateSlide);
+      setIndication(initialValues.indication);
+      setAudioText(initialValues.audioText);
+      setModifyAudio(initialValues.modifyAudio);
+      setMediaType(initialValues.mediaType);
+      setMediaPrompt(initialValues.mediaPrompt);
+      setThemeId(initialValues.themeId || defaultThemeId);
+    } else {
+      setTitle(outline.title);
+      setRegenerateSlide(true);
+      setIndication(outlineToIndication(outline.description, outline.keyPoints));
+      setAudioText(sceneToAudioText(scene));
+      setModifyAudio(false);
+      const mt = outlineToMediaType(outline);
+      setMediaType(mt);
+      setMediaPrompt(mt === 'keep' ? '' : outlineToMediaPrompt(outline, mt));
+      setThemeId(defaultThemeId);
+    }
+    // Fetch available themes
+    fetch('/api/themes')
+      .then((r) => r.json())
+      .then((data: ThemeListItem[]) => setThemes(data))
+      .catch(() => {
+        /* theme list stays empty, selector hidden */
+      });
+  }, [open, outline, scene, initialValues, defaultThemeId]);
+
+  // Abort in-flight fetches when dialog closes
+  useEffect(() => {
+    if (!open) {
+      promptAbortRef.current?.abort();
+      narrationAbortRef.current?.abort();
+    }
+  }, [open]);
+
+  // Abort on unmount
+  useEffect(() => {
+    return () => {
+      promptAbortRef.current?.abort();
+      narrationAbortRef.current?.abort();
+    };
+  }, []);
+
+  const generateNarration = useCallback(
+    async (currentIndication: string) => {
+      narrationAbortRef.current?.abort();
+      const ctrl = new AbortController();
+      narrationAbortRef.current = ctrl;
+
+      setIsGeneratingNarration(true);
+      setNarrationError(null);
+      try {
+        const config = getCurrentModelConfig();
+        const res = await fetch('/api/generate/narration-text', {
+          method: 'POST',
+          headers: {
+            'Content-Type': 'application/json',
+            'x-model': config.modelString || '',
+            'x-provider-type': config.providerType || '',
+          },
+          body: JSON.stringify({
+            indicationText: currentIndication,
+            language: outline.language,
+          }),
+          signal: ctrl.signal,
+        });
+        if (ctrl.signal.aborted) return;
+        const json = await res.json();
+        if (json.success && json.data?.text) {
+          setAudioText(json.data.text);
+        } else {
+          setNarrationError(json.error || t('stage.regen.aiGenerationError'));
+        }
+      } catch (err) {
+        if (err instanceof DOMException && err.name === 'AbortError') return;
+        setNarrationError(t('stage.regen.aiGenerationError'));
+      } finally {
+        if (!ctrl.signal.aborted) setIsGeneratingNarration(false);
+      }
+    },
+    [outline.language, t],
+  );
+
+  const generatePromptForType = useCallback(
+    async (type: 'image' | 'video', currentIndication: string) => {
+      // Cancel any in-flight request
+      promptAbortRef.current?.abort();
+      const ctrl = new AbortController();
+      promptAbortRef.current = ctrl;
+
+      setIsGeneratingPrompt(true);
+      setMediaPrompt('');
+      setPromptError(null);
+      try {
+        const config = getCurrentModelConfig();
+        const res = await fetch('/api/generate/media-prompt', {
+          method: 'POST',
+          headers: {
+            'Content-Type': 'application/json',
+            'x-model': config.modelString || '',
+            'x-provider-type': config.providerType || '',
+          },
+          body: JSON.stringify({
+            indicationText: currentIndication,
+            mediaType: type,
+            language: outline.language,
+          }),
+          signal: ctrl.signal,
+        });
+        if (ctrl.signal.aborted) return;
+        const json = await res.json();
+        if (json.success && json.data?.prompt) {
+          setMediaPrompt(json.data.prompt);
+        } else {
+          setPromptError(json.error || t('stage.regen.aiGenerationError'));
+        }
+      } catch (err) {
+        if (err instanceof DOMException && err.name === 'AbortError') return;
+        setPromptError(t('stage.regen.aiGenerationError'));
+      } finally {
+        if (!ctrl.signal.aborted) setIsGeneratingPrompt(false);
+      }
+    },
+    [outline.language, t],
+  );
+
+  const handleMediaTypeChange = useCallback(
+    (value: 'none' | 'image' | 'video' | 'keep') => {
+      setMediaType(value);
+      if (value === 'none' || value === 'keep') {
+        setMediaPrompt('');
+        promptAbortRef.current?.abort();
+        return;
+      }
+      // Check if original outline already has a prompt for this type
+      const existingPrompt = outlineToMediaPrompt(outline, value);
+      if (existingPrompt) {
+        setMediaPrompt(existingPrompt);
+      } else {
+        generatePromptForType(value, indication);
+      }
+    },
+    [outline, generatePromptForType, indication],
+  );
+
+  // Conflict: new media requested without slide toggle, but slide has no existing media slot
+  const hasExistingMedia = outlineToMediaType(outline) !== 'none';
+  const needsNewMedia = mediaType === 'image' || mediaType === 'video';
+  const showSlideWarning = !regenerateSlide && needsNewMedia && !hasExistingMedia;
+
+  const handleSubmit = () => {
+    const forceSlideRegen = !regenerateSlide && needsNewMedia && !hasExistingMedia;
+    const updatedOutline: SceneOutline =
+      regenerateSlide || forceSlideRegen
+        ? { ...outline, title, ...indicationToOutline(indication) }
+        : { ...outline };
+    // Do NOT call onClose() here — Stage closes the dialog by transitioning
+    // regenState from 'dialog_open' to 'regenerating'. Calling onClose() would
+    // race with setRegenState('regenerating') and the batch winner is 'idle',
+    // leaving the dialog open throughout the entire regeneration.
+    onRegenerate({
+      outline: updatedOutline,
+      audioTextOverride: modifyAudio ? audioText : '',
+      mediaType,
+      mediaPrompt: mediaType !== 'none' && mediaType !== 'keep' ? mediaPrompt : undefined,
+      skipAudio: !modifyAudio,
+      skipSlide: !regenerateSlide && !forceSlideRegen,
+      themeId: themeId || undefined,
+    });
+  };
+
+  const isSubmitDisabled =
+    isGeneratingPrompt || (mediaType !== 'none' && mediaType !== 'keep' && !mediaPrompt.trim());
+
+  return (
+    <Dialog open={open} onOpenChange={(o) => !o && onClose()}>
+      <DialogContent className="max-w-4xl max-h-[90vh] flex flex-col overflow-hidden">
+        <DialogHeader>
+          <DialogTitle className="text-purple-700 dark:text-purple-300">
+            <span aria-hidden="true">↺</span> {t('stage.regen.dialogTitle')} — {title}
+          </DialogTitle>
+          <DialogDescription className="sr-only">
+            {t('stage.regen.dialogTitle')} — {title}
+          </DialogDescription>
+        </DialogHeader>
+
+        {errorMessage && (
+          <div className="mx-1 px-3 py-2 rounded-md bg-red-50 dark:bg-red-950/30 border border-red-200 dark:border-red-800 text-sm text-red-700 dark:text-red-300">
+            <span className="font-semibold">Error: </span>
+            {errorMessage}
+          </div>
+        )}
+
+        <div className="flex-1 overflow-y-auto space-y-4 px-1 py-2">
+          {/* Slide block */}
+          <div className="space-y-1.5">
+            <div className="flex items-center justify-between">
+              <Label className="text-xs font-semibold uppercase tracking-wide text-muted-foreground">
+                {t('stage.regen.indication')}
+              </Label>
+              <div className="flex items-center gap-2">
+                <span className="text-xs text-muted-foreground">
+                  {t('stage.regen.modifySlide')}
+                </span>
+                <Switch
+                  id="regen-modify-slide"
+                  checked={regenerateSlide}
+                  onCheckedChange={setRegenerateSlide}
+                />
+              </div>
+            </div>
+            {regenerateSlide ? (
+              <>
+                <div className="space-y-1">
+                  <Label htmlFor="regen-title" className="text-xs text-muted-foreground">
+                    {t('stage.regen.slideTitle')}
+                  </Label>
+                  <Input
+                    id="regen-title"
+                    value={title}
+                    onChange={(e) => setTitle(e.target.value)}
+                    className="h-8 text-sm"
+                  />
+                </div>
+                <Textarea
+                  id="regen-indication"
+                  value={indication}
+                  onChange={(e) => setIndication(e.target.value)}
+                  rows={4}
+                  className="resize-none text-sm"
+                  placeholder={t('stage.regen.indicationPlaceholder')}
+                />
+                {themes.length > 0 && (
+                  <div className="space-y-1.5">
+                    <Label className="text-xs font-semibold uppercase tracking-wide text-muted-foreground">
+                      {t('stage.regen.theme')}
+                    </Label>
+                    <Select value={themeId} onValueChange={setThemeId}>
+                      <SelectTrigger className="h-8 text-sm">
+                        <SelectValue>
+                          {(() => {
+                            const active = themes.find((th) => th.id === themeId);
+                            return active ? (
+                              <span className="flex items-center gap-2">
+                                <span
+                                  className="w-3 h-3 rounded-sm border border-border/50 shrink-0"
+                                  style={{ background: active.colors.primary }}
+                                />
+                                {active.name}
+                              </span>
+                            ) : (
+                              <span className="text-muted-foreground">
+                                {t('stage.regen.theme')}
+                              </span>
+                            );
+                          })()}
+                        </SelectValue>
+                      </SelectTrigger>
+                      <SelectContent>
+                        {themes.map((theme) => (
+                          <SelectItem key={theme.id} value={theme.id}>
+                            <span className="flex items-center gap-2">
+                              <span
+                                className="w-3 h-3 rounded-sm border border-border/50 shrink-0"
+                                style={{ background: theme.colors.primary }}
+                              />
+                              {theme.name}
+                            </span>
+                          </SelectItem>
+                        ))}
+                      </SelectContent>
+                    </Select>
+                  </div>
+                )}
+              </>
+            ) : (
+              <p className="text-xs text-muted-foreground py-1">{t('stage.regen.slideKeep')}</p>
+            )}
+          </div>
+
+          {/* Conflict warning: new media requested but slide has no existing media slot */}
+          {showSlideWarning && (
+            <div className="mx-1 px-3 py-2 rounded-md bg-amber-50 dark:bg-amber-950/30 border border-amber-200 dark:border-amber-800 text-sm text-amber-700 dark:text-amber-300">
+              ⚠ {t('stage.regen.slideWarningMediaNeeded')}
+            </div>
+          )}
+
+          {/* Audio text */}
+          <div className="space-y-1.5">
+            <div className="flex items-center justify-between">
+              <Label
+                htmlFor="regen-audio-text"
+                className="text-xs font-semibold uppercase tracking-wide text-muted-foreground"
+              >
+                {t('stage.regen.audioText')}
+              </Label>
+              <div className="flex items-center gap-2">
+                <span className="text-xs text-muted-foreground">
+                  {t('stage.regen.modifyAudio')}
+                </span>
+                <Switch
+                  id="regen-modify-audio"
+                  checked={modifyAudio}
+                  onCheckedChange={setModifyAudio}
+                />
+              </div>
+            </div>
+            {modifyAudio ? (
+              <div className="space-y-1">
+                <Textarea
+                  id="regen-audio-text"
+                  value={audioText}
+                  onChange={(e) => setAudioText(e.target.value)}
+                  rows={5}
+                  disabled={isGeneratingNarration}
+                  className="resize-none text-sm"
+                  placeholder={t('stage.regen.audioTextPlaceholder')}
+                />
+                <div className="flex items-center justify-between gap-2">
+                  {narrationError ? (
+                    <p className="text-xs text-red-600 dark:text-red-400 flex-1">
+                      {narrationError} {t('stage.regen.aiModelHint')}
+                    </p>
+                  ) : (
+                    <span />
+                  )}
+                  <Button
+                    type="button"
+                    size="sm"
+                    variant="outline"
+                    disabled={isGeneratingNarration || !indication.trim()}
+                    onClick={() => generateNarration(indication)}
+                    className="h-7 text-xs gap-1.5 shrink-0 text-violet-700 dark:text-violet-300 border-violet-200 dark:border-violet-700 hover:bg-violet-50 dark:hover:bg-violet-950/30"
+                  >
+                    <Sparkles className="size-3.5" />
+                    {isGeneratingNarration
+                      ? t('stage.regen.generatingNarration')
+                      : t('stage.regen.generateNarration')}
+                  </Button>
+                </div>
+              </div>
+            ) : (
+              <p className="text-xs text-muted-foreground py-1">{t('stage.regen.audioKeep')}</p>
+            )}
+          </div>
+
+          {/* Media selector */}
+          <div className="space-y-2">
+            <Label
+              id="regen-media-label"
+              className="text-xs font-semibold uppercase tracking-wide text-muted-foreground"
+            >
+              {t('stage.regen.media')}
+            </Label>
+            <div role="group" aria-labelledby="regen-media-label" className="flex gap-2 flex-wrap">
+              {(['keep', 'none', 'image', 'video'] as const).map((opt) => (
+                <Button
+                  key={opt}
+                  type="button"
+                  size="sm"
+                  variant={mediaType === opt ? 'default' : 'outline'}
+                  onClick={() => handleMediaTypeChange(opt)}
+                >
+                  {t(`stage.regen.media${opt.charAt(0).toUpperCase() + opt.slice(1)}`)}
+                </Button>
+              ))}
+            </div>
+
+            {mediaType !== 'none' && mediaType !== 'keep' && (
+              <div className="space-y-1">
+                {isGeneratingPrompt ? (
+                  <p className="text-xs text-blue-500 dark:text-blue-400 animate-pulse">
+                    ✨ {t('stage.regen.generatingPrompt')}
+                  </p>
+                ) : promptError ? (
+                  <p className="text-xs text-red-600 dark:text-red-400">
+                    {promptError} {t('stage.regen.aiModelHint')}
+                  </p>
+                ) : (
+                  <p className="text-xs text-muted-foreground">
+                    {outlineToMediaPrompt(outline, mediaType)
+                      ? t('stage.regen.promptOriginal')
+                      : t('stage.regen.promptAutoGenerated')}
+                  </p>
+                )}
+                <Textarea
+                  value={mediaPrompt}
+                  onChange={(e) => setMediaPrompt(e.target.value)}
+                  rows={3}
+                  disabled={isGeneratingPrompt}
+                  className="resize-none text-sm"
+                  placeholder={t('stage.regen.mediaPromptPlaceholder')}
+                />
+              </div>
+            )}
+          </div>
+        </div>
+
+        <DialogFooter className="pt-2 flex-row items-center">
+          {/* Model controls — left side */}
+          <div className="flex items-center gap-1.5 mr-auto">
+            <CompactModelSelector />
+            <MediaPopover onSettingsOpen={() => {}} />
+          </div>
+          {/* Actions — right side */}
+          <Button variant="ghost" onClick={onClose}>
+            {t('stage.regen.cancel')}
+          </Button>
+          <Button
+            onClick={handleSubmit}
+            disabled={isSubmitDisabled}
+            className="bg-purple-600 hover:bg-purple-700 text-white"
+          >
+            <span aria-hidden="true">↺</span> {t('stage.regen.regenerate')}
+          </Button>
+        </DialogFooter>
+      </DialogContent>
+    </Dialog>
+  );
+}
diff --git a/components/generation/generation-toolbar.tsx b/components/generation/generation-toolbar.tsx
index 7673eb05c..a313967a1 100644
--- a/components/generation/generation-toolbar.tsx
+++ b/components/generation/generation-toolbar.tsx
@@ -22,6 +22,8 @@ import type { ProviderId } from '@/lib/ai/providers';
 import { MONO_LOGO_PROVIDERS } from '@/lib/ai/providers';
 import type { SettingsSection } from '@/lib/types/settings';
 import { MediaPopover } from '@/components/generation/media-popover';
+import { ModelSelectorPopover } from '@/components/generation/model-selector-popover';
+import type { ConfiguredProvider } from '@/components/generation/model-selector-popover';
 
 // ─── Constants ───────────────────────────────────────────────
 const MAX_PDF_SIZE_MB = 50;
@@ -380,185 +382,3 @@ export function GenerationToolbar({
     </div>
   );
 }
-
-// ─── ModelSelectorPopover (two-level: provider → model) ─────
-interface ConfiguredProvider {
-  id: ProviderId;
-  name: string;
-  icon?: string;
-  isServerConfigured?: boolean;
-  models: { id: string; name: string }[];
-}
-
-function ModelSelectorPopover({
-  configuredProviders,
-  currentProviderId,
-  currentModelId,
-  currentProviderConfig,
-  setModel,
-  t,
-}: {
-  configuredProviders: ConfiguredProvider[];
-  currentProviderId: ProviderId;
-  currentModelId: string;
-  currentProviderConfig: { name: string; icon?: string } | undefined;
-  setModel: (providerId: ProviderId, modelId: string) => void;
-  t: (key: string) => string;
-}) {
-  const [popoverOpen, setPopoverOpen] = useState(false);
-  // null = provider list, ProviderId = model list for that provider
-  const [drillProvider, setDrillProvider] = useState<ProviderId | null>(null);
-
-  const activeProvider = useMemo(
-    () => configuredProviders.find((p) => p.id === drillProvider),
-    [configuredProviders, drillProvider],
-  );
-
-  return (
-    <Popover
-      open={popoverOpen}
-      onOpenChange={(open) => {
-        setPopoverOpen(open);
-        if (open) setDrillProvider(null);
-      }}
-    >
-      <Tooltip>
-        <TooltipTrigger asChild>
-          <PopoverTrigger asChild>
-            <button
-              className={cn(
-                'inline-flex items-center justify-center size-7 rounded-full transition-all cursor-pointer select-none',
-                'ring-1 ring-border/60 hover:ring-border hover:bg-muted/60',
-                currentModelId &&
-                  'ring-violet-300 dark:ring-violet-700 bg-violet-50 dark:bg-violet-950/20',
-              )}
-            >
-              {currentProviderConfig?.icon ? (
-                <img
-                  src={currentProviderConfig.icon}
-                  alt={currentProviderConfig.name}
-                  className={cn(
-                    'size-4 rounded-sm',
-                    MONO_LOGO_PROVIDERS.has(currentProviderId) && 'dark:invert',
-                  )}
-                />
-              ) : (
-                <Bot className="size-3.5 text-muted-foreground" />
-              )}
-            </button>
-          </PopoverTrigger>
-        </TooltipTrigger>
-        <TooltipContent>
-          {currentModelId
-            ? `${currentProviderConfig?.name || currentProviderId} / ${currentModelId}`
-            : t('settings.selectModel')}
-        </TooltipContent>
-      </Tooltip>
-
-      <PopoverContent align="start" className="w-64 p-0">
-        {/* Level 1: Provider list */}
-        {!drillProvider && (
-          <div className="max-h-72 overflow-y-auto">
-            <div className="px-3 py-2 border-b">
-              <span className="text-xs font-semibold text-muted-foreground">
-                {t('toolbar.selectProvider')}
-              </span>
-            </div>
-            {configuredProviders.map((provider) => {
-              const isActive = currentProviderId === provider.id;
-              return (
-                <button
-                  key={provider.id}
-                  onClick={() => setDrillProvider(provider.id)}
-                  className={cn(
-                    'w-full flex items-center gap-2.5 px-3 py-2.5 text-left transition-colors border-b border-border/30',
-                    isActive ? 'bg-violet-50/50 dark:bg-violet-950/10' : 'hover:bg-muted/50',
-                  )}
-                >
-                  {provider.icon ? (
-                    <img
-                      src={provider.icon}
-                      alt={provider.name}
-                      className={cn(
-                        'size-5 rounded-sm shrink-0',
-                        MONO_LOGO_PROVIDERS.has(provider.id) && 'dark:invert',
-                      )}
-                    />
-                  ) : (
-                    <Bot className="size-5 text-muted-foreground shrink-0" />
-                  )}
-                  <div className="flex-1 min-w-0">
-                    <span className="text-sm font-medium">{provider.name}</span>
-                    {provider.isServerConfigured && (
-                      <span className="text-[9px] px-1 py-0 rounded border text-muted-foreground ml-1.5">
-                        {t('settings.serverConfigured')}
-                      </span>
-                    )}
-                  </div>
-                  {isActive && currentModelId && (
-                    <span className="text-[10px] text-muted-foreground truncate max-w-[80px]">
-                      {currentModelId}
-                    </span>
-                  )}
-                </button>
-              );
-            })}
-          </div>
-        )}
-
-        {/* Level 2: Model list for selected provider */}
-        {drillProvider && activeProvider && (
-          <div className="max-h-72 overflow-y-auto">
-            {/* Back header */}
-            <button
-              onClick={() => setDrillProvider(null)}
-              className="w-full flex items-center gap-2 px-3 py-2 border-b bg-muted/40 hover:bg-muted/60 transition-colors"
-            >
-              <ChevronLeft className="size-3.5 text-muted-foreground" />
-              {activeProvider.icon ? (
-                <img
-                  src={activeProvider.icon}
-                  alt={activeProvider.name}
-                  className={cn(
-                    'size-4 rounded-sm',
-                    MONO_LOGO_PROVIDERS.has(activeProvider.id) && 'dark:invert',
-                  )}
-                />
-              ) : (
-                <Bot className="size-4 text-muted-foreground" />
-              )}
-              <span className="text-xs font-semibold">{activeProvider.name}</span>
-              <span className="text-[10px] text-muted-foreground ml-auto">
-                {activeProvider.models.length} {t('settings.modelCount')}
-              </span>
-            </button>
-            {/* Models */}
-            {activeProvider.models.map((model) => {
-              const isSelected = currentProviderId === drillProvider && currentModelId === model.id;
-              return (
-                <button
-                  key={model.id}
-                  onClick={() => {
-                    setModel(drillProvider, model.id);
-                    setPopoverOpen(false);
-                  }}
-                  className={cn(
-                    'w-full flex items-center gap-2 px-3 py-2 text-left transition-colors border-b border-border/30',
-                    isSelected
-                      ? 'bg-violet-50 dark:bg-violet-950/20 text-violet-700 dark:text-violet-300'
-                      : 'hover:bg-muted/50',
-                  )}
-                >
-                  <span className="flex-1 truncate font-mono text-xs">{model.name}</span>
-                  {isSelected && (
-                    <Check className="size-3.5 shrink-0 text-violet-600 dark:text-violet-400" />
-                  )}
-                </button>
-              );
-            })}
-          </div>
-        )}
-      </PopoverContent>
-    </Popover>
-  );
-}
diff --git a/components/generation/model-selector-popover.tsx b/components/generation/model-selector-popover.tsx
new file mode 100644
index 000000000..7cd5fbc92
--- /dev/null
+++ b/components/generation/model-selector-popover.tsx
@@ -0,0 +1,244 @@
+'use client';
+
+import { useState, useMemo } from 'react';
+import { Bot, Check, ChevronLeft } from 'lucide-react';
+import { Popover, PopoverContent, PopoverTrigger } from '@/components/ui/popover';
+import { Tooltip, TooltipContent, TooltipTrigger } from '@/components/ui/tooltip';
+import { cn } from '@/lib/utils';
+import { useI18n } from '@/lib/hooks/use-i18n';
+import { useSettingsStore } from '@/lib/store/settings';
+import { useUserPrefsStore } from '@/lib/store/user-prefs';
+import { MONO_LOGO_PROVIDERS } from '@/lib/ai/providers';
+import type { ProviderId } from '@/lib/ai/providers';
+
+export interface ConfiguredProvider {
+  id: ProviderId;
+  name: string;
+  icon?: string;
+  isServerConfigured?: boolean;
+  models: { id: string; name: string }[];
+}
+
+interface ModelSelectorPopoverProps {
+  configuredProviders: ConfiguredProvider[];
+  currentProviderId: ProviderId;
+  currentModelId: string;
+  currentProviderConfig: { name: string; icon?: string } | undefined;
+  setModel: (providerId: ProviderId, modelId: string) => void;
+  t: (key: string) => string;
+}
+
+export function ModelSelectorPopover({
+  configuredProviders,
+  currentProviderId,
+  currentModelId,
+  currentProviderConfig,
+  setModel,
+  t,
+}: ModelSelectorPopoverProps) {
+  const [popoverOpen, setPopoverOpen] = useState(false);
+  // null = provider list, ProviderId = model list for that provider
+  const [drillProvider, setDrillProvider] = useState<ProviderId | null>(null);
+
+  const activeProvider = useMemo(
+    () => configuredProviders.find((p) => p.id === drillProvider),
+    [configuredProviders, drillProvider],
+  );
+
+  return (
+    <Popover
+      open={popoverOpen}
+      onOpenChange={(open) => {
+        setPopoverOpen(open);
+        if (open) setDrillProvider(null);
+      }}
+    >
+      <Tooltip>
+        <TooltipTrigger asChild>
+          <PopoverTrigger asChild>
+            <button
+              className={cn(
+                'inline-flex items-center justify-center size-7 rounded-full transition-all cursor-pointer select-none',
+                'ring-1 ring-border/60 hover:ring-border hover:bg-muted/60',
+                currentModelId &&
+                  'ring-violet-300 dark:ring-violet-700 bg-violet-50 dark:bg-violet-950/20',
+              )}
+            >
+              {currentProviderConfig?.icon ? (
+                <img
+                  src={currentProviderConfig.icon}
+                  alt={currentProviderConfig.name}
+                  className={cn(
+                    'size-4 rounded-sm',
+                    MONO_LOGO_PROVIDERS.has(currentProviderId) && 'dark:invert',
+                  )}
+                />
+              ) : (
+                <Bot className="size-3.5 text-muted-foreground" />
+              )}
+            </button>
+          </PopoverTrigger>
+        </TooltipTrigger>
+        <TooltipContent>
+          {currentModelId
+            ? `${currentProviderConfig?.name || currentProviderId} / ${currentModelId}`
+            : t('settings.selectModel')}
+        </TooltipContent>
+      </Tooltip>
+
+      <PopoverContent align="start" className="w-64 p-0">
+        {/* Level 1: Provider list */}
+        {!drillProvider && (
+          <div className="max-h-72 overflow-y-auto">
+            <div className="px-3 py-2 border-b">
+              <span className="text-xs font-semibold text-muted-foreground">
+                {t('toolbar.selectProvider')}
+              </span>
+            </div>
+            {configuredProviders.map((provider) => {
+              const isActive = currentProviderId === provider.id;
+              return (
+                <button
+                  key={provider.id}
+                  onClick={() => setDrillProvider(provider.id)}
+                  className={cn(
+                    'w-full flex items-center gap-2.5 px-3 py-2.5 text-left transition-colors border-b border-border/30',
+                    isActive ? 'bg-violet-50/50 dark:bg-violet-950/10' : 'hover:bg-muted/50',
+                  )}
+                >
+                  {provider.icon ? (
+                    <img
+                      src={provider.icon}
+                      alt={provider.name}
+                      className={cn(
+                        'size-5 rounded-sm shrink-0',
+                        MONO_LOGO_PROVIDERS.has(provider.id) && 'dark:invert',
+                      )}
+                    />
+                  ) : (
+                    <Bot className="size-5 text-muted-foreground shrink-0" />
+                  )}
+                  <div className="flex-1 min-w-0">
+                    <span className="text-sm font-medium">{provider.name}</span>
+                    {provider.isServerConfigured && (
+                      <span className="text-[9px] px-1 py-0 rounded border text-muted-foreground ml-1.5">
+                        {t('settings.serverConfigured')}
+                      </span>
+                    )}
+                  </div>
+                  {isActive && currentModelId && (
+                    <span className="text-[10px] text-muted-foreground truncate max-w-[80px]">
+                      {currentModelId}
+                    </span>
+                  )}
+                </button>
+              );
+            })}
+          </div>
+        )}
+
+        {/* Level 2: Model list for selected provider */}
+        {drillProvider && activeProvider && (
+          <div className="max-h-72 overflow-y-auto">
+            <button
+              onClick={() => setDrillProvider(null)}
+              className="w-full flex items-center gap-2 px-3 py-2 border-b bg-muted/40 hover:bg-muted/60 transition-colors"
+            >
+              <ChevronLeft className="size-3.5 text-muted-foreground" />
+              {activeProvider.icon ? (
+                <img
+                  src={activeProvider.icon}
+                  alt={activeProvider.name}
+                  className={cn(
+                    'size-4 rounded-sm',
+                    MONO_LOGO_PROVIDERS.has(activeProvider.id) && 'dark:invert',
+                  )}
+                />
+              ) : (
+                <Bot className="size-4 text-muted-foreground" />
+              )}
+              <span className="text-xs font-semibold">{activeProvider.name}</span>
+              <span className="text-[10px] text-muted-foreground ml-auto">
+                {activeProvider.models.length} {t('settings.modelCount')}
+              </span>
+            </button>
+            {activeProvider.models.map((model) => {
+              const isSelected = currentProviderId === drillProvider && currentModelId === model.id;
+              return (
+                <button
+                  key={model.id}
+                  onClick={() => {
+                    setModel(drillProvider, model.id);
+                    setPopoverOpen(false);
+                  }}
+                  className={cn(
+                    'w-full flex items-center gap-2 px-3 py-2 text-left transition-colors border-b border-border/30',
+                    isSelected
+                      ? 'bg-violet-50 dark:bg-violet-950/20 text-violet-700 dark:text-violet-300'
+                      : 'hover:bg-muted/50',
+                  )}
+                >
+                  <span className="flex-1 truncate font-mono text-xs">{model.name}</span>
+                  {isSelected && (
+                    <Check className="size-3.5 shrink-0 text-violet-600 dark:text-violet-400" />
+                  )}
+                </button>
+              );
+            })}
+          </div>
+        )}
+      </PopoverContent>
+    </Popover>
+  );
+}
+
+/**
+ * Self-contained wrapper that reads from Zustand stores directly.
+ * Drop-in for contexts where you don't want to manage store subscriptions.
+ */
+export function CompactModelSelector() {
+  const { t } = useI18n();
+  const currentProviderId = useUserPrefsStore((s) => s.providerId);
+  const currentModelId = useUserPrefsStore((s) => s.modelId);
+  const providersConfig = useSettingsStore((s) => s.providersConfig);
+  const setModel = useUserPrefsStore((s) => s.setModel);
+
+  const configuredProviders = useMemo(
+    () =>
+      providersConfig
+        ? Object.entries(providersConfig)
+            .filter(
+              ([, config]) =>
+                (!config.requiresApiKey || config.apiKey || config.isServerConfigured) &&
+                config.models.length >= 1 &&
+                (config.baseUrl || config.defaultBaseUrl || config.serverBaseUrl),
+            )
+            .map(([id, config]) => ({
+              id: id as ProviderId,
+              name: config.name,
+              icon: config.icon,
+              isServerConfigured: config.isServerConfigured,
+              models:
+                config.isServerConfigured && !config.apiKey && config.serverModels?.length
+                  ? config.models.filter((m) => new Set(config.serverModels).has(m.id))
+                  : config.models,
+            }))
+        : [],
+    [providersConfig],
+  );
+
+  const currentProviderConfig = providersConfig?.[currentProviderId];
+
+  if (configuredProviders.length === 0) return null;
+
+  return (
+    <ModelSelectorPopover
+      configuredProviders={configuredProviders}
+      currentProviderId={currentProviderId}
+      currentModelId={currentModelId}
+      currentProviderConfig={currentProviderConfig}
+      setModel={setModel}
+      t={t}
+    />
+  );
+}
diff --git a/components/stage.tsx b/components/stage.tsx
index 04b826fc6..34442fd18 100644
--- a/components/stage.tsx
+++ b/components/stage.tsx
@@ -32,6 +32,20 @@ import {
 } from '@/components/ui/alert-dialog';
 import { AlertTriangle } from 'lucide-react';
 import { VisuallyHidden } from 'radix-ui';
+import { Button } from '@/components/ui/button';
+import {
+  useSceneRegenerator,
+  outlineToIndication,
+  type RegenerateParams,
+} from '@/lib/hooks/use-scene-regenerator';
+import {
+  RegenerateSlideDialog,
+  type RegenerateFormValues,
+} from '@/components/classroom/regenerate-slide-dialog';
+import type { Scene } from '@/lib/types/stage';
+import type { SceneOutline } from '@/lib/types/generation';
+
+type RegenState = 'idle' | 'dialog_open' | 'regenerating' | 'review';
 
 /**
  * Stage Component
@@ -46,8 +60,15 @@ export function Stage({
   onRetryOutline?: (outlineId: string) => Promise<void>;
 }) {
   const { t } = useI18n();
-  const { mode, getCurrentScene, scenes, currentSceneId, setCurrentSceneId, generatingOutlines } =
-    useStageStore();
+  const {
+    mode,
+    getCurrentScene,
+    scenes,
+    outlines,
+    currentSceneId,
+    setCurrentSceneId,
+    generatingOutlines,
+  } = useStageStore();
   const failedOutlines = useStageStore.use.failedOutlines();
 
   const currentScene = getCurrentScene();
@@ -98,6 +119,13 @@ export function Stage({
 
   // Scene switch confirmation dialog state
   const [pendingSceneId, setPendingSceneId] = useState<string | null>(null);
+  // Regenerate-slide state machine
+  const [regenState, setRegenState] = useState<RegenState>('idle');
+  const [backupScene, setBackupScene] = useState<Scene | null>(null);
+  const [backupOutline, setBackupOutline] = useState<SceneOutline | null>(null);
+  const [lastRegenValues, setLastRegenValues] = useState<RegenerateFormValues | null>(null);
+  const [pendingRegenSceneId, setPendingRegenSceneId] = useState<string | null>(null);
+  const [regenErrorMessage, setRegenErrorMessage] = useState<string | null>(null);
   const [isPresenting, setIsPresenting] = useState(false);
   const [controlsVisible, setControlsVisible] = useState(true);
   const [isPresentationInteractionActive, setIsPresentationInteractionActive] = useState(false);
@@ -169,6 +197,7 @@ export function Stage({
   const sceneEpochRef = useRef(0);
   // When true, the next engine init will auto-start playback (for auto-play scene advance)
   const autoStartRef = useRef(false);
+  const sceneRegenerator = useSceneRegenerator();
   // Discussion buffer-level pause state (distinct from soft-pause which aborts SSE)
   const [isDiscussionPaused, setIsDiscussionPaused] = useState(false);
 
@@ -659,6 +688,108 @@ export function Stage({
 
   const isTopicActive = playbackView.isTopicActive;
 
+  /** Open the regeneration dialog for the current scene */
+  const openRegenerateDialog = useCallback(() => {
+    if (!currentScene || currentScene.type !== 'slide') return;
+    setRegenState('dialog_open');
+  }, [currentScene]);
+
+  /** Called when the dialog submits — starts the regeneration pipeline */
+  const handleRegenerate = useCallback(
+    async (params: RegenerateParams) => {
+      const scene = getCurrentScene();
+      if (!scene || scene.type !== 'slide') return;
+      const outline = useStageStore.getState().outlines.find((o) => o.order === scene.order);
+      // When skipAudio, preserve the current narration text for display in case
+      // the user activates "Modify narration" on a subsequent retry.
+      const storedAudioText =
+        (params.skipAudio ?? false)
+          ? (scene.actions ?? [])
+              .filter((a): a is SpeechAction => a.type === 'speech')
+              .map((a) => a.text)
+              .join('\n\n')
+          : params.audioTextOverride;
+      setLastRegenValues({
+        title: params.outline.title,
+        regenerateSlide: !(params.skipSlide ?? false),
+        indication: outlineToIndication(
+          outline?.description ?? params.outline.description,
+          outline?.keyPoints ?? params.outline.keyPoints,
+        ),
+        audioText: storedAudioText,
+        modifyAudio: !(params.skipAudio ?? false),
+        mediaType: params.mediaType,
+        mediaPrompt: params.mediaPrompt ?? '',
+        themeId: params.themeId ?? '',
+      });
+      // Capture backup in local vars — setState calls are async (batched),
+      // so closure-captured state would be stale in the failure/undo branches.
+      const backup = { ...scene };
+      const outlineBackup = outline ? { ...outline } : null;
+      setBackupScene(backup);
+      setBackupOutline(outlineBackup);
+      setRegenState('regenerating');
+      const result = await sceneRegenerator.regenerate(scene.id, params);
+      if (!result.success) {
+        // Restore backup and re-open dialog so user can retry
+        useStageStore.getState().updateScene(scene.id, {
+          content: backup.content,
+          actions: backup.actions,
+        });
+        // Also restore the outline in case Step 4 already ran before the failure
+        if (outlineBackup) {
+          const freshOutlines = useStageStore.getState().outlines;
+          useStageStore
+            .getState()
+            .setOutlines(
+              freshOutlines.map((o) => (o.order === outlineBackup.order ? outlineBackup : o)),
+            );
+        }
+        setRegenErrorMessage(result.error ?? null);
+        setRegenState('dialog_open');
+        return;
+      }
+      setRegenErrorMessage(null);
+      setRegenState('review');
+    },
+    [getCurrentScene, sceneRegenerator],
+  );
+
+  /** Accept the new version: clear backup, return to idle */
+  const handleRegenAccept = useCallback(() => {
+    setBackupScene(null);
+    setBackupOutline(null);
+    setLastRegenValues(null);
+    setRegenState('idle');
+  }, []);
+
+  /** Undo: restore backup scene + outline to store, return to idle */
+  const handleRegenUndo = useCallback(() => {
+    if (backupScene && currentScene) {
+      useStageStore.getState().updateScene(currentScene.id, {
+        content: backupScene.content,
+        actions: backupScene.actions,
+      });
+    }
+    if (backupOutline) {
+      const freshOutlines = useStageStore.getState().outlines;
+      useStageStore
+        .getState()
+        .setOutlines(
+          freshOutlines.map((o) => (o.order === backupOutline.order ? backupOutline : o)),
+        );
+    }
+    setBackupScene(null);
+    setBackupOutline(null);
+    setLastRegenValues(null);
+    setRegenState('idle');
+  }, [backupScene, backupOutline, currentScene]);
+
+  /** Reopen dialog with previously entered values */
+  const handleRegenEditAgain = useCallback(() => {
+    setRegenState('dialog_open');
+  }, []);
+
   /**
    * Gated scene switch — if a topic is active, show AlertDialog before switching.
    * Returns true if the switch was immediate, false if gated (dialog shown).
@@ -670,10 +801,15 @@ export function Stage({
         setPendingSceneId(targetSceneId);
         return false;
       }
+      // If a regenerated version is pending review, show regen confirm dialog
+      if (regenState === 'review') {
+        setPendingRegenSceneId(targetSceneId);
+        return false;
+      }
       setCurrentSceneId(targetSceneId);
       return true;
     },
-    [currentSceneId, isTopicActive, setCurrentSceneId],
+    [currentSceneId, isTopicActive, regenState, setCurrentSceneId],
   );
 
   /** User confirmed scene switch via AlertDialog */
@@ -690,6 +826,42 @@ export function Stage({
     setPendingSceneId(null);
   }, []);
 
+  /** User chose "Sí, conservar" in regen confirm modal */
+  const confirmRegenKeep = useCallback(() => {
+    if (!pendingRegenSceneId) return;
+    setBackupScene(null);
+    setBackupOutline(null);
+    setLastRegenValues(null);
+    setRegenState('idle');
+    setCurrentSceneId(pendingRegenSceneId);
+    setPendingRegenSceneId(null);
+  }, [pendingRegenSceneId, setCurrentSceneId]);
+
+  /** User chose "Descartar" in regen confirm modal */
+  const confirmRegenDiscard = useCallback(() => {
+    if (!pendingRegenSceneId) return;
+    if (backupScene && currentScene) {
+      useStageStore.getState().updateScene(currentScene.id, {
+        content: backupScene.content,
+        actions: backupScene.actions,
+      });
+    }
+    if (backupOutline) {
+      const freshOutlines = useStageStore.getState().outlines;
+      useStageStore
+        .getState()
+        .setOutlines(
+          freshOutlines.map((o) => (o.order === backupOutline.order ? backupOutline : o)),
+        );
+    }
+    setBackupScene(null);
+    setBackupOutline(null);
+    setLastRegenValues(null);
+    setRegenState('idle');
+    setCurrentSceneId(pendingRegenSceneId);
+    setPendingRegenSceneId(null);
+  }, [backupScene, backupOutline, currentScene, pendingRegenSceneId, setCurrentSceneId]);
+
   // play/pause toggle
   const handlePlayPause = useCallback(async () => {
     const engine = engineRef.current;
@@ -936,6 +1108,14 @@ export function Stage({
         onCollapseChange={setSidebarCollapsed}
         onSceneSelect={gatedSceneSwitch}
         onRetryOutline={onRetryOutline}
+        regenState={
+          regenState === 'regenerating'
+            ? 'regenerating'
+            : regenState === 'review'
+              ? 'review'
+              : 'idle'
+        }
+        onRegenerateClick={openRegenerateDialog}
       />
 
       {/* Main Content Area */}
@@ -989,6 +1169,69 @@ export function Stage({
           />
         </div>
 
+        {/* Progress bar — shown while regeneration is in progress */}
+        {regenState === 'regenerating' && (
+          <div className="shrink-0 flex items-center gap-3 px-4 py-2 bg-purple-50 dark:bg-purple-950/30 border-t border-purple-200 dark:border-purple-800 text-sm">
+            <svg
+              className="animate-spin h-4 w-4 text-purple-500 shrink-0"
+              xmlns="http://www.w3.org/2000/svg"
+              fill="none"
+              viewBox="0 0 24 24"
+              aria-hidden="true"
+            >
+              <circle
+                className="opacity-25"
+                cx="12"
+                cy="12"
+                r="10"
+                stroke="currentColor"
+                strokeWidth="4"
+              />
+              <path
+                className="opacity-75"
+                fill="currentColor"
+                d="M4 12a8 8 0 018-8V0C5.373 0 0 5.373 0 12h4z"
+              />
+            </svg>
+            <span className="text-purple-700 dark:text-purple-300 font-medium">
+              {sceneRegenerator.progress === 'audio'
+                ? t('stage.regen.stepAudio')
+                : sceneRegenerator.progress === 'media'
+                  ? t('stage.regen.stepMedia')
+                  : t('stage.regen.stepContent')}
+            </span>
+          </div>
+        )}
+
+        {/* Review bar — shown when a regenerated version is pending acceptance */}
+        {regenState === 'review' && (
+          <div className="shrink-0 flex items-center justify-between gap-3 px-4 py-2 bg-green-50 dark:bg-green-950/30 border-t border-green-200 dark:border-green-800 text-sm">
+            <span className="text-green-700 dark:text-green-300 font-medium">
+              {t('stage.regen.reviewBar')}
+            </span>
+            <div className="flex gap-2">
+              <Button size="sm" variant="outline" onClick={handleRegenEditAgain}>
+                ✏ {t('stage.regen.editAgain')}
+              </Button>
+              <Button
+                size="sm"
+                variant="outline"
+                className="text-red-600 border-red-300 hover:bg-red-50 dark:text-red-400 dark:border-red-700 dark:hover:bg-red-950/30"
+                onClick={handleRegenUndo}
+              >
+                ↩ {t('stage.regen.undo')}
+              </Button>
+              <Button
+                size="sm"
+                className="bg-green-600 hover:bg-green-700 text-white"
+                onClick={handleRegenAccept}
+              >
+                ✓ {t('stage.regen.accept')}
+              </Button>
+            </div>
+          </div>
+        )}
+
         {/* Roundtable Area */}
         {mode === 'playback' && (
           <div
@@ -1231,6 +1474,66 @@ export function Stage({
           </AlertDialogFooter>
         </AlertDialogContent>
       </AlertDialog>
+
+      {/* Regenerate Slide Dialog */}
+      {(() => {
+        if (!currentScene || currentScene.type !== 'slide') return null;
+        if (regenState !== 'dialog_open') return null;
+        const outline = outlines.find((o) => o.order === currentScene.order);
+        if (!outline) return null;
+        return (
+          <RegenerateSlideDialog
+            open={true}
+            scene={currentScene}
+            outline={outline}
+            initialValues={lastRegenValues ?? undefined}
+            errorMessage={regenErrorMessage ?? undefined}
+            onRegenerate={handleRegenerate}
+            onClose={() => {
+              setRegenState('idle');
+              setRegenErrorMessage(null);
+            }}
+          />
+        );
+      })()}
+
+      {/* Regen confirm modal — shown when navigating away during review */}
+      <AlertDialog
+        open={!!pendingRegenSceneId}
+        onOpenChange={(open) => {
+          if (!open) setPendingRegenSceneId(null);
+        }}
+      >
+        <AlertDialogContent className="max-w-md rounded-2xl">
+          <VisuallyHidden.Root>
+            <AlertDialogTitle>{t('stage.regen.confirmTitle')}</AlertDialogTitle>
+          </VisuallyHidden.Root>
+          <div className="px-6 pt-6">
+            <div className="flex items-start gap-3">
+              <AlertTriangle className="w-5 h-5 text-amber-500 shrink-0 mt-0.5" />
+              <div>
+                <p className="font-semibold text-gray-900 dark:text-gray-100 mb-1">
+                  {t('stage.regen.confirmTitle')}
+                </p>
+                <p className="text-sm text-gray-600 dark:text-gray-400">
+                  {t('stage.regen.confirmBody').replace('{title}', currentScene?.title ?? '')}
+                </p>
+              </div>
+            </div>
+          </div>
+          <AlertDialogFooter className="px-6 pb-5 pt-3 flex-row gap-3">
+            <AlertDialogCancel onClick={confirmRegenDiscard} className="flex-1 rounded-xl">
+              {t('stage.regen.confirmDiscard')}
+            </AlertDialogCancel>
+            <AlertDialogAction
+              onClick={confirmRegenKeep}
+              className="flex-1 rounded-xl bg-green-600 hover:bg-green-700"
+            >
+              {t('stage.regen.confirmKeep')}
+            </AlertDialogAction>
+          </AlertDialogFooter>
+        </AlertDialogContent>
+      </AlertDialog>
     </div>
   );
 }
diff --git a/components/stage/scene-sidebar.tsx b/components/stage/scene-sidebar.tsx
index 4b75471a2..5d4811344 100644
--- a/components/stage/scene-sidebar.tsx
+++ b/components/stage/scene-sidebar.tsx
@@ -24,6 +24,9 @@ interface SceneSidebarProps {
   readonly onCollapseChange: (collapsed: boolean) => void;
   readonly onSceneSelect?: (sceneId: string) => void;
   readonly onRetryOutline?: (outlineId: string) => Promise<void>;
+  // 'regenerating' and 'review' states handled by parent — sidebar only gates button visibility
+  readonly regenState?: 'idle' | 'regenerating' | 'review';
+  readonly onRegenerateClick?: () => void;
 }
 
 const DEFAULT_WIDTH = 220;
@@ -35,6 +38,8 @@ export function SceneSidebar({
   onCollapseChange,
   onSceneSelect,
   onRetryOutline,
+  regenState = 'idle',
+  onRegenerateClick,
 }: SceneSidebarProps) {
   const { t } = useI18n();
   const router = useRouter();
@@ -319,6 +324,20 @@ export function SceneSidebar({
                     )}
                   </div>
                 </div>
+
+                {isActive && isSlide && onRegenerateClick && (
+                  <button
+                    disabled={regenState !== 'idle'}
+                    onClick={(e) => {
+                      e.stopPropagation();
+                      if (regenState === 'idle') onRegenerateClick();
+                    }}
+                    title={t('stage.regen.buttonLabel')}
+                    className="w-full mt-1 py-0.5 px-2 text-[10px] font-semibold rounded border border-purple-200 dark:border-purple-700 text-purple-600 dark:text-purple-400 hover:bg-purple-50 dark:hover:bg-purple-900/30 transition-colors flex items-center justify-center gap-1 disabled:opacity-40 disabled:cursor-not-allowed disabled:hover:bg-transparent"
+                  >
+                    <span aria-hidden="true">↺</span> {t('stage.regen.buttonLabel')}
+                  </button>
+                )}
               </div>
             );
           })}
diff --git a/docs/superpowers/plans/2026-04-12-regenerate-slide-blocks.md b/docs/superpowers/plans/2026-04-12-regenerate-slide-blocks.md
new file mode 100644
index 000000000..58569ba71
--- /dev/null
+++ b/docs/superpowers/plans/2026-04-12-regenerate-slide-blocks.md
@@ -0,0 +1,754 @@
+# Regenerate Slide — Block Toggles + Title Editing Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** Add a slide block toggle and editable title field to the regenerate-slide dialog, plus `skipSlide` support in the regeneration hook.
+
+**Architecture:** Three parallel changes: (1) i18n keys, (2) `resolveSkipSlide` pure helper + `RegenerateParams.skipSlide` in the hook, (3) UI updates to the dialog. Hook `skipSlide` logic wraps Steps 1a+1b; media re-renders automatically via the existing `useMediaGenerationStore` subscription in `SlideRenderer` (no canvas patching needed — `elementInfo.src === 'gen_img_1'` is the store key).
+
+**Tech Stack:** React 19, TypeScript strict, Zustand 5, shadcn/ui (`Switch`, `Input`, `Label`), Vitest 4, i18n JSON (5 locales).
+
+---
+
+## File Map
+
+| File | Change |
+|------|--------|
+| `lib/i18n/locales/ca.json` | Add 4 keys: `modifySlide`, `slideTitle`, `slideKeep`, `slideWarningMediaNeeded` |
+| `lib/i18n/locales/en-US.json` | Same 4 keys |
+| `lib/i18n/locales/zh-CN.json` | Same 4 keys |
+| `lib/i18n/locales/ja-JP.json` | Same 4 keys |
+| `lib/i18n/locales/ru-RU.json` | Same 4 keys |
+| `lib/hooks/use-scene-regenerator.ts` | Add `skipSlide?: boolean` to `RegenerateParams`; export `resolveSkipSlide`; extend pre-step; wrap Steps 1a+1b; add `title` to `updateScene` |
+| `tests/hooks/use-scene-regenerator.test.ts` | Add `resolveSkipSlide` test suite |
+| `components/classroom/regenerate-slide-dialog.tsx` | Add `title`/`regenerateSlide` state; import `Input`; slide block toggle + title input; conflict warning; bind `DialogTitle` |
+
+---
+
+### Task 1: i18n — Add new regen keys to all 5 locales
+
+**Files:**
+- Modify: `lib/i18n/locales/ca.json`
+- Modify: `lib/i18n/locales/en-US.json`
+- Modify: `lib/i18n/locales/zh-CN.json`
+- Modify: `lib/i18n/locales/ja-JP.json`
+- Modify: `lib/i18n/locales/ru-RU.json`
+
+Each file's `stage.regen` object currently ends with:
+```json
+"modifyAudio": "...",
+"audioKeep": "...",
+"generateNarration": "...",
+"generatingNarration": "...",
+"aiGenerationError": "...",
+"aiModelHint": "..."
+```
+
+- [ ] **Step 1: Add keys to ca.json**
+
+In `lib/i18n/locales/ca.json`, find the line `"modifyAudio": "Modificar narració",` and insert the 4 new keys immediately after it:
+
+```json
+      "modifyAudio": "Modificar narració",
+      "modifySlide": "Modificar slide",
+      "slideTitle": "Títol",
+      "slideKeep": "La slide actual es conservarà.",
+      "slideWarningMediaNeeded": "Per afegir nova imatge/vídeo, la slide s'haurà de regenerar igualment.",
+```
+
+- [ ] **Step 2: Add keys to en-US.json**
+
+Find `"modifyAudio": "Modify narration",` and insert after:
+
+```json
+      "modifyAudio": "Modify narration",
+      "modifySlide": "Modify slide",
+      "slideTitle": "Title",
+      "slideKeep": "Existing slide will be preserved.",
+      "slideWarningMediaNeeded": "To add new image/video, the slide must also be regenerated.",
+```
+
+- [ ] **Step 3: Add keys to zh-CN.json**
+
+Find `"modifyAudio": "修改旁白",` and insert after:
+
+```json
+      "modifyAudio": "修改旁白",
+      "modifySlide": "修改幻灯片",
+      "slideTitle": "标题",
+      "slideKeep": "现有幻灯片将被保留。",
+      "slideWarningMediaNeeded": "添加新图片/视频时，幻灯片也将被重新生成。",
+```
+
+- [ ] **Step 4: Add keys to ja-JP.json**
+
+Find `"modifyAudio": "ナレーションを変更",` and insert after:
+
+```json
+      "modifyAudio": "ナレーションを変更",
+      "modifySlide": "スライドを変更",
+      "slideTitle": "タイトル",
+      "slideKeep": "既存のスライドが保持されます。",
+      "slideWarningMediaNeeded": "新しい画像/動画を追加するには、スライドも再生成する必要があります。",
+```
+
+- [ ] **Step 5: Add keys to ru-RU.json**
+
+Find `"modifyAudio": "Изменить нарратив",` and insert after:
+
+```json
+      "modifyAudio": "Изменить нарратив",
+      "modifySlide": "Изменить слайд",
+      "slideTitle": "Заголовок",
+      "slideKeep": "Существующий слайд будет сохранён.",
+      "slideWarningMediaNeeded": "Для добавления нового изображения/видео слайд также будет регенерирован.",
+```
+
+- [ ] **Step 6: Commit**
+
+```bash
+git add lib/i18n/locales/ca.json lib/i18n/locales/en-US.json lib/i18n/locales/zh-CN.json lib/i18n/locales/ja-JP.json lib/i18n/locales/ru-RU.json
+git commit -m "feat(regen): add i18n keys for slide block toggle and title"
+```
+
+---
+
+### Task 2: Export `resolveSkipSlide` helper + update `RegenerateParams`
+
+**Files:**
+- Modify: `lib/hooks/use-scene-regenerator.ts`
+
+- [ ] **Step 1: Add `skipSlide` to `RegenerateParams`**
+
+In `lib/hooks/use-scene-regenerator.ts`, find the `RegenerateParams` interface (around line 69) and add the new field:
+
+```typescript
+export interface RegenerateParams {
+  outline: SceneOutline;
+  audioTextOverride: string;
+  mediaType: 'none' | 'image' | 'video' | 'keep';
+  mediaPrompt?: string;
+  /** When true, skip TTS generation and preserve existing speech audio from the scene. */
+  skipAudio?: boolean;
+  /** When true, skip slide content + actions generation and preserve the existing slide. */
+  skipSlide?: boolean;
+  /** Theme to apply during content generation. Falls back to server-side stage default. */
+  themeId?: string;
+}
+```
+
+- [ ] **Step 2: Export `resolveSkipSlide` pure helper**
+
+Add the following function to the "Pure helpers" section (after `applyAudioOverride`, before `// ── Types ──`):
+
+```typescript
+/**
+ * Resolves the effective `skipSlide` value.
+ * When new media is requested but the existing slide has no media slot,
+ * the slide must be regenerated even if skipSlide was requested.
+ */
+export function resolveSkipSlide(
+  skipSlide: boolean,
+  mediaType: 'none' | 'image' | 'video' | 'keep',
+  hasExistingMediaSlot: boolean,
+): boolean {
+  if (!skipSlide) return false;
+  if (mediaType === 'none' || mediaType === 'keep') return true;
+  // New media requested — only skip if there is already a media element to replace
+  return hasExistingMediaSlot;
+}
+```
+
+- [ ] **Step 3: Commit**
+
+```bash
+git add lib/hooks/use-scene-regenerator.ts
+git commit -m "feat(regen): add skipSlide to RegenerateParams and export resolveSkipSlide helper"
+```
+
+---
+
+### Task 3: Tests for `resolveSkipSlide`
+
+**Files:**
+- Modify: `tests/hooks/use-scene-regenerator.test.ts`
+
+- [ ] **Step 1: Write failing tests**
+
+Add the following test suite at the end of `tests/hooks/use-scene-regenerator.test.ts`:
+
+```typescript
+import {
+  outlineToIndication,
+  indicationToOutline,
+  buildMediaGenerations,
+  applyAudioOverride,
+  resolveSkipSlide,
+} from '@/lib/hooks/use-scene-regenerator';
+
+// ... existing suites ...
+
+describe('resolveSkipSlide', () => {
+  it('returns false when skipSlide is false regardless of other args', () => {
+    expect(resolveSkipSlide(false, 'image', true)).toBe(false);
+    expect(resolveSkipSlide(false, 'none', false)).toBe(false);
+  });
+
+  it('returns true when skipSlide and mediaType is none', () => {
+    expect(resolveSkipSlide(true, 'none', false)).toBe(true);
+  });
+
+  it('returns true when skipSlide and mediaType is keep', () => {
+    expect(resolveSkipSlide(true, 'keep', false)).toBe(true);
+  });
+
+  it('returns true when skipSlide, new image requested, and existing slot present', () => {
+    expect(resolveSkipSlide(true, 'image', true)).toBe(true);
+  });
+
+  it('returns true when skipSlide, new video requested, and existing slot present', () => {
+    expect(resolveSkipSlide(true, 'video', true)).toBe(true);
+  });
+
+  it('returns false when skipSlide, new image requested, but no existing slot', () => {
+    expect(resolveSkipSlide(true, 'image', false)).toBe(false);
+  });
+
+  it('returns false when skipSlide, new video requested, but no existing slot', () => {
+    expect(resolveSkipSlide(true, 'video', false)).toBe(false);
+  });
+});
+```
+
+- [ ] **Step 2: Run tests and verify they fail**
+
+```bash
+pnpm test -- tests/hooks/use-scene-regenerator.test.ts --reporter=verbose
+```
+
+Expected: 7 new tests fail with "resolveSkipSlide is not a function" (because the export doesn't exist yet — if you committed Task 2 first, they should PASS instead; run to confirm all pass).
+
+- [ ] **Step 3: Verify all tests pass**
+
+If Task 2 was completed first, tests should already pass. Confirm:
+
+```bash
+pnpm test -- tests/hooks/use-scene-regenerator.test.ts --reporter=verbose
+```
+
+Expected output: all tests PASS including the 7 new `resolveSkipSlide` tests.
+
+- [ ] **Step 4: Commit**
+
+```bash
+git add tests/hooks/use-scene-regenerator.test.ts
+git commit -m "test(regen): add resolveSkipSlide unit tests"
+```
+
+---
+
+### Task 4: Hook — implement `skipSlide` + title in `updateScene`
+
+**Files:**
+- Modify: `lib/hooks/use-scene-regenerator.ts`
+
+This task modifies the `regenerate` function inside `useSceneRegenerator`. Read the current implementation carefully before editing — there are several interdependent sections.
+
+- [ ] **Step 1: Extend pre-step to capture existing scene when `skipSlide` is requested**
+
+Find the pre-step block (around line 153) that starts with:
+```typescript
+if (params.skipAudio || params.mediaType === 'keep') {
+```
+
+Replace the entire pre-step block with:
+
+```typescript
+// Pre-step: capture existing data from the current scene before any update
+const existingSpeechActions: SpeechAction[] = [];
+type MediaElementInfo = { type: 'image' | 'video'; src: string };
+const existingMediaElements: MediaElementInfo[] = [];
+let oldSceneContent: SceneContent | null = null;
+let oldSceneActions: Action[] | null = null;
+
+if (params.skipAudio || params.mediaType === 'keep' || params.skipSlide) {
+  const oldScene = store.getState().scenes.find((s) => s.id === sceneId);
+  if (oldScene) {
+    if (params.skipAudio) {
+      for (const action of oldScene.actions ?? []) {
+        if (action.type === 'speech') existingSpeechActions.push(action as SpeechAction);
+      }
+    }
+    if ((params.mediaType === 'keep' || params.skipSlide) && oldScene.type === 'slide') {
+      for (const el of (oldScene.content as SlideContent).canvas.elements) {
+        if ((el.type === 'image' || el.type === 'video') && el.src) {
+          existingMediaElements.push({ type: el.type, src: el.src });
+        }
+      }
+    }
+    if (params.skipSlide) {
+      oldSceneContent = oldScene.content;
+      oldSceneActions = [...(oldScene.actions ?? [])];
+    }
+  }
+}
+```
+
+- [ ] **Step 2: Compute `effectiveSkipSlide` after the pre-step**
+
+Immediately after the pre-step block (before `// Resolve the effective media type for the outline:`), add:
+
+```typescript
+// Resolve effective skipSlide: if new media is requested but there's no existing slot,
+// we must regenerate the slide to create a placeholder element.
+const effectiveSkipSlide = resolveSkipSlide(
+  params.skipSlide ?? false,
+  params.mediaType,
+  existingMediaElements.length > 0,
+);
+```
+
+- [ ] **Step 3: Wrap Steps 1a + 1b in `if (!effectiveSkipSlide)` block**
+
+Find the section that starts at `// ── Step 1a: Generate slide content ──` and ends at the line:
+```typescript
+// Immediately show new slide content (without audio yet)
+store.getState().updateScene(sceneId, { content: newContent, actions: newActions });
+```
+
+Replace that entire section (Steps 1a, 1b, keep-media injection, and the immediate `updateScene` call) with:
+
+```typescript
+// ── Steps 1a + 1b: Generate slide content and actions (or use existing) ──
+let contentData: unknown;
+let newActions: Action[];
+let newContent: SceneContent;
+
+if (effectiveSkipSlide) {
+  // Use the existing scene — no content or actions regeneration
+  if (!oldSceneContent || !oldSceneActions) {
+    log.error('Cannot skipSlide: existing scene content not captured');
+    setProgress('error');
+    setErrorStep('content');
+    return { success: false, error: 'Existing scene not found' };
+  }
+  newContent = oldSceneContent;
+  newActions = oldSceneActions;
+} else {
+  // ── Step 1a: Generate slide content ──
+  try {
+    const contentRes = await fetch('/api/generate/scene-content-only', {
+      method: 'POST',
+      headers: getApiHeaders(),
+      body: JSON.stringify({ outline, stageId, themeId: params.themeId }),
+      signal,
+    });
+    const json = await contentRes.json();
+    if (!contentRes.ok || !json.success) {
+      throw new Error(json.error || `HTTP ${contentRes.status}`);
+    }
+    contentData = json.data;
+  } catch (err) {
+    if (signal.aborted) return { success: false };
+    log.error('Step 1 (content) failed:', err);
+    setProgress('error');
+    setErrorStep('content');
+    return { success: false, error: err instanceof Error ? err.message : String(err) };
+  }
+
+  if (signal.aborted) return { success: false };
+
+  // ── Step 1b: Generate scene actions ──
+  try {
+    const actionsRes = await fetch('/api/generate/scene-actions', {
+      method: 'POST',
+      headers: getApiHeaders(),
+      body: JSON.stringify({
+        outline,
+        allOutlines,
+        content: contentData,
+        stageId,
+      }),
+      signal,
+    });
+    const json = await actionsRes.json();
+    if (!actionsRes.ok || !json.success || !json.scene) {
+      throw new Error(json.error || `HTTP ${actionsRes.status}`);
+    }
+    if (!json.scene.content) {
+      throw new Error('Missing scene content in actions response');
+    }
+    newActions = json.scene.actions ?? [];
+    newContent = json.scene.content;
+  } catch (err) {
+    if (signal.aborted) return { success: false };
+    log.error('Step 1 (actions) failed:', err);
+    setProgress('error');
+    setErrorStep('content');
+    return { success: false, error: err instanceof Error ? err.message : String(err) };
+  }
+
+  if (signal.aborted) return { success: false };
+
+  // When keeping existing media, inject old src values into new content elements
+  if (params.mediaType === 'keep' && existingMediaElements.length > 0 && newContent.type === 'slide') {
+    const slideContent = newContent as SlideContent;
+    const updatedElements = slideContent.canvas.elements.map((el) => {
+      if (el.type === 'image') {
+        const old = existingMediaElements.find((e) => e.type === 'image');
+        if (old) return { ...el, src: old.src };
+      } else if (el.type === 'video') {
+        const old = existingMediaElements.find((e) => e.type === 'video');
+        if (old) return { ...el, src: old.src };
+      }
+      return el;
+    });
+    newContent = { ...slideContent, canvas: { ...slideContent.canvas, elements: updatedElements } };
+  }
+
+  // Immediately show new slide content (without audio yet)
+  store.getState().updateScene(sceneId, { title: outline.title, content: newContent, actions: newActions });
+}
+```
+
+- [ ] **Step 4: Verify TypeScript compiles**
+
+```bash
+pnpm exec tsc --noEmit 2>&1 | grep "use-scene-regenerator"
+```
+
+Expected: no errors.
+
+- [ ] **Step 5: Run existing tests to confirm no regression**
+
+```bash
+pnpm test -- tests/hooks/use-scene-regenerator.test.ts --reporter=verbose
+```
+
+Expected: all tests PASS.
+
+- [ ] **Step 6: Commit**
+
+```bash
+git add lib/hooks/use-scene-regenerator.ts
+git commit -m "feat(regen): implement skipSlide in regeneration hook and propagate outline.title"
+```
+
+---
+
+### Task 5: Dialog — slide block toggle + title input + conflict warning
+
+**Files:**
+- Modify: `components/classroom/regenerate-slide-dialog.tsx`
+
+- [ ] **Step 1: Add `Input` import and new state fields**
+
+At the top of `components/classroom/regenerate-slide-dialog.tsx`, add `Input` to the ui imports. Find the line:
+```typescript
+import { Textarea } from '@/components/ui/textarea';
+```
+Add after it:
+```typescript
+import { Input } from '@/components/ui/input';
+```
+
+Also add `resolveSkipSlide` to the import from `use-scene-regenerator`. Find:
+```typescript
+import { outlineToIndication, indicationToOutline } from '@/lib/hooks/use-scene-regenerator';
+```
+Replace with:
+```typescript
+import { outlineToIndication, indicationToOutline, resolveSkipSlide } from '@/lib/hooks/use-scene-regenerator';
+```
+
+- [ ] **Step 2: Update `RegenerateFormValues` interface**
+
+Find:
+```typescript
+export interface RegenerateFormValues {
+  indication: string;
+  audioText: string;
+  modifyAudio: boolean;
+  mediaType: 'none' | 'image' | 'video' | 'keep';
+  mediaPrompt: string;
+  themeId: string;
+}
+```
+Replace with:
+```typescript
+export interface RegenerateFormValues {
+  title: string;
+  indication: string;
+  regenerateSlide: boolean;
+  audioText: string;
+  modifyAudio: boolean;
+  mediaType: 'none' | 'image' | 'video' | 'keep';
+  mediaPrompt: string;
+  themeId: string;
+}
+```
+
+- [ ] **Step 3: Add new state variables**
+
+Find the state declarations block (around line 89):
+```typescript
+const [indication, setIndication] = useState('');
+const [audioText, setAudioText] = useState('');
+```
+Add two new state lines immediately before `const [indication`:
+```typescript
+const [title, setTitle] = useState('');
+const [regenerateSlide, setRegenerateSlide] = useState(true);
+const [indication, setIndication] = useState('');
+const [audioText, setAudioText] = useState('');
+```
+
+- [ ] **Step 4: Update `useEffect` initialisation**
+
+Inside the `useEffect` that runs on `open`, find the `if (initialValues)` branch:
+```typescript
+    if (initialValues) {
+      setIndication(initialValues.indication);
+      setAudioText(initialValues.audioText);
+      setModifyAudio(initialValues.modifyAudio);
+      setMediaType(initialValues.mediaType);
+      setMediaPrompt(initialValues.mediaPrompt);
+      setThemeId(initialValues.themeId || defaultThemeId);
+    } else {
+      setIndication(outlineToIndication(outline.description, outline.keyPoints));
+      setAudioText(sceneToAudioText(scene));
+      setModifyAudio(false);
+      const mt = outlineToMediaType(outline);
+      setMediaType(mt);
+      setMediaPrompt(mt === 'keep' ? '' : outlineToMediaPrompt(outline, mt));
+      setThemeId(defaultThemeId);
+    }
+```
+Replace with:
+```typescript
+    if (initialValues) {
+      setTitle(initialValues.title);
+      setRegenerateSlide(initialValues.regenerateSlide);
+      setIndication(initialValues.indication);
+      setAudioText(initialValues.audioText);
+      setModifyAudio(initialValues.modifyAudio);
+      setMediaType(initialValues.mediaType);
+      setMediaPrompt(initialValues.mediaPrompt);
+      setThemeId(initialValues.themeId || defaultThemeId);
+    } else {
+      setTitle(outline.title);
+      setRegenerateSlide(true);
+      setIndication(outlineToIndication(outline.description, outline.keyPoints));
+      setAudioText(sceneToAudioText(scene));
+      setModifyAudio(false);
+      const mt = outlineToMediaType(outline);
+      setMediaType(mt);
+      setMediaPrompt(mt === 'keep' ? '' : outlineToMediaPrompt(outline, mt));
+      setThemeId(defaultThemeId);
+    }
+```
+
+- [ ] **Step 5: Compute derived warning flag**
+
+Immediately before the `handleSubmit` function, add:
+```typescript
+  // Conflict: media requested without slide toggle, but slide has no existing media slot
+  const hasExistingMedia = outlineToMediaType(outline) !== 'none';
+  const needsNewMedia = mediaType === 'image' || mediaType === 'video';
+  const showSlideWarning = !regenerateSlide && needsNewMedia && !hasExistingMedia;
+```
+
+- [ ] **Step 6: Update `handleSubmit`**
+
+Find the entire `handleSubmit` function and replace it:
+```typescript
+  const handleSubmit = () => {
+    const { description, keyPoints } = indicationToOutline(indication);
+    const updatedOutline: SceneOutline = {
+      ...outline,
+      title: regenerateSlide ? title : outline.title,
+      description,
+      keyPoints,
+    };
+    const forceSlideRegen = !regenerateSlide && needsNewMedia && !hasExistingMedia;
+    onRegenerate({
+      outline: updatedOutline,
+      audioTextOverride: modifyAudio ? audioText : '',
+      mediaType,
+      mediaPrompt: mediaType !== 'none' && mediaType !== 'keep' ? mediaPrompt : undefined,
+      skipAudio: !modifyAudio,
+      skipSlide: !regenerateSlide && !forceSlideRegen,
+      themeId: themeId || undefined,
+    });
+  };
+```
+
+- [ ] **Step 7: Bind `DialogTitle` to the live `title` state**
+
+Find in the JSX:
+```tsx
+          <DialogTitle className="text-purple-700 dark:text-purple-300">
+            <span aria-hidden="true">↺</span> {t('stage.regen.dialogTitle')} — {scene.title}
+          </DialogTitle>
+          <DialogDescription className="sr-only">
+            {t('stage.regen.dialogTitle')} — {scene.title}
+          </DialogDescription>
+```
+Replace both `{scene.title}` references with `{title}`:
+```tsx
+          <DialogTitle className="text-purple-700 dark:text-purple-300">
+            <span aria-hidden="true">↺</span> {t('stage.regen.dialogTitle')} — {title}
+          </DialogTitle>
+          <DialogDescription className="sr-only">
+            {t('stage.regen.dialogTitle')} — {title}
+          </DialogDescription>
+```
+
+- [ ] **Step 8: Replace the slide block section in the form**
+
+Find the current `{/* Indication */}` section and the `{/* Theme selector */}` section that follow it. Replace both sections (from `{/* Indication */}` through the closing `)}` of the theme selector) with the new slide block that includes the toggle, title input, indication, and theme selector:
+
+```tsx
+          {/* Slide block */}
+          <div className="space-y-1.5">
+            <div className="flex items-center justify-between">
+              <Label className="text-xs font-semibold uppercase tracking-wide text-muted-foreground">
+                {t('stage.regen.indication')}
+              </Label>
+              <div className="flex items-center gap-2">
+                <span className="text-xs text-muted-foreground">{t('stage.regen.modifySlide')}</span>
+                <Switch
+                  id="regen-modify-slide"
+                  checked={regenerateSlide}
+                  onCheckedChange={setRegenerateSlide}
+                />
+              </div>
+            </div>
+            {regenerateSlide ? (
+              <>
+                <div className="space-y-1">
+                  <Label htmlFor="regen-title" className="text-xs text-muted-foreground">
+                    {t('stage.regen.slideTitle')}
+                  </Label>
+                  <Input
+                    id="regen-title"
+                    value={title}
+                    onChange={(e) => setTitle(e.target.value)}
+                    className="h-8 text-sm"
+                  />
+                </div>
+                <Textarea
+                  id="regen-indication"
+                  value={indication}
+                  onChange={(e) => setIndication(e.target.value)}
+                  rows={4}
+                  className="resize-none text-sm"
+                  placeholder={t('stage.regen.indicationPlaceholder')}
+                />
+                {themes.length > 0 && (
+                  <div className="space-y-1.5">
+                    <Label className="text-xs font-semibold uppercase tracking-wide text-muted-foreground">
+                      {t('stage.regen.theme')}
+                    </Label>
+                    <Select value={themeId} onValueChange={setThemeId}>
+                      <SelectTrigger className="h-8 text-sm">
+                        <SelectValue>
+                          {(() => {
+                            const active = themes.find((th) => th.id === themeId);
+                            return active ? (
+                              <span className="flex items-center gap-2">
+                                <span
+                                  className="w-3 h-3 rounded-sm border border-border/50 shrink-0"
+                                  style={{ background: active.colors.primary }}
+                                />
+                                {active.name}
+                              </span>
+                            ) : (
+                              <span className="text-muted-foreground">{t('stage.regen.theme')}</span>
+                            );
+                          })()}
+                        </SelectValue>
+                      </SelectTrigger>
+                      <SelectContent>
+                        {themes.map((theme) => (
+                          <SelectItem key={theme.id} value={theme.id}>
+                            <span className="flex items-center gap-2">
+                              <span
+                                className="w-3 h-3 rounded-sm border border-border/50 shrink-0"
+                                style={{ background: theme.colors.primary }}
+                              />
+                              {theme.name}
+                            </span>
+                          </SelectItem>
+                        ))}
+                      </SelectContent>
+                    </Select>
+                  </div>
+                )}
+              </>
+            ) : (
+              <p className="text-xs text-muted-foreground py-1">
+                {t('stage.regen.slideKeep')}
+              </p>
+            )}
+          </div>
+
+          {/* Conflict warning: new media requested but slide has no existing media slot */}
+          {showSlideWarning && (
+            <div className="mx-1 px-3 py-2 rounded-md bg-amber-50 dark:bg-amber-950/30 border border-amber-200 dark:border-amber-800 text-sm text-amber-700 dark:text-amber-300">
+              ⚠ {t('stage.regen.slideWarningMediaNeeded')}
+            </div>
+          )}
+```
+
+- [ ] **Step 9: TypeScript check**
+
+```bash
+pnpm exec tsc --noEmit 2>&1 | grep "regenerate-slide-dialog"
+```
+
+Expected: no errors.
+
+- [ ] **Step 10: Run full unit test suite**
+
+```bash
+pnpm test --reporter=verbose
+```
+
+Expected: all tests PASS.
+
+- [ ] **Step 11: Commit**
+
+```bash
+git add components/classroom/regenerate-slide-dialog.tsx
+git commit -m "feat(regen): add slide block toggle, title input, and conflict warning to dialog"
+```
+
+---
+
+## Self-Review Checklist
+
+**Spec coverage:**
+- [x] Slide block toggle (`regenerateSlide` / `modifySlide` switch) — Task 5
+- [x] Editable title field — Task 5
+- [x] `<DialogTitle>` live binding — Task 5 Step 7
+- [x] Conflict warning (amber banner) — Task 5 Step 8
+- [x] `RegenerateFormValues.title` + `regenerateSlide` — Task 5 Steps 2–4
+- [x] `RegenerateParams.skipSlide` — Task 2
+- [x] `resolveSkipSlide` pure helper — Task 2 + Task 3
+- [x] Hook: skip Steps 1a+1b when `effectiveSkipSlide` — Task 4
+- [x] Hook: `title: outline.title` in `updateScene` — Task 4 Step 3
+- [x] `forceSlideRegen` logic in `handleSubmit` — Task 5 Step 6
+- [x] `initialValues` includes `title` and `regenerateSlide` — Task 5 Step 4
+- [x] i18n: 4 new keys × 5 locales — Task 1
+- [x] Unit tests for `resolveSkipSlide` — Task 3
+
+**Placeholder scan:** No TBD, no TODO, no "similar to above", all code blocks complete.
+
+**Type consistency:**
+- `resolveSkipSlide` exported in Task 2, imported in Task 5 Step 1 ✓
+- `RegenerateFormValues.title` defined in Task 5 Step 2, read in Task 5 Step 4 ✓
+- `RegenerateParams.skipSlide` defined in Task 2, set in Task 5 Step 6, consumed in Task 4 ✓
+- `effectiveSkipSlide` computed in Task 4 Step 2, used in Task 4 Step 3 ✓
+- `oldSceneContent`/`oldSceneActions` captured in Task 4 Step 1, used in Task 4 Step 3 ✓
+- `showSlideWarning` computed in Task 5 Step 5, used in Task 5 Steps 6 and 8 ✓
diff --git a/docs/superpowers/plans/2026-04-12-regenerate-slide.md b/docs/superpowers/plans/2026-04-12-regenerate-slide.md
new file mode 100644
index 000000000..947217147
--- /dev/null
+++ b/docs/superpowers/plans/2026-04-12-regenerate-slide.md
@@ -0,0 +1,1639 @@
+# Regenerate Slide Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** Allow users to edit a slide's indication, audio text, and media type in a dialog, then regenerate only that slide incrementally (content → audio → media) with a backup/review/accept flow.
+
+**Architecture:** New synchronous endpoint `scene-content-only` generates raw slide layout without persisting; a client hook `useSceneRegenerator` orchestrates 4 pipeline steps updating Zustand state after each one; Stage manages an idle/dialog/regenerating/review state machine with backup/restore logic.
+
+**Tech Stack:** Next.js App Router API routes, Zustand 5, Vercel AI SDK (`callLLM`), shadcn Dialog + RadioGroup + Textarea, existing `generateAndStoreTTS`, `generateSingleMedia` (newly exported from media-orchestrator).
+
+---
+
+## File Map
+
+| File | Action | Responsibility |
+|------|--------|----------------|
+| `app/api/generate/scene-content-only/route.ts` | **Create** | Synchronous slide content generation without persisting a scene |
+| `app/api/generate/media-prompt/route.ts` | **Create** | Auto-generate a media prompt from an indication text |
+| `lib/media/media-orchestrator.ts` | **Modify** | Export `generateSingleMedia` as `generateAndStoreMedia` |
+| `lib/hooks/use-scene-regenerator.ts` | **Create** | 4-step client pipeline: content → actions → audio → media |
+| `components/classroom/regenerate-slide-dialog.tsx` | **Create** | Edit dialog (indication, audio text, media selector + prompt) |
+| `components/stage/scene-sidebar.tsx` | **Modify** | Add ↺ Regen. button below active slide thumbnail |
+| `components/stage.tsx` | **Modify** | State machine, backup management, review bar, confirm modal |
+| `tests/hooks/use-scene-regenerator.test.ts` | **Create** | Unit tests for pre-step outline building and audio split logic |
+
+---
+
+## Task 1: API endpoint `POST /api/generate/scene-content-only`
+
+**Files:**
+- Create: `app/api/generate/scene-content-only/route.ts`
+- Test: `tests/api/scene-content-only.test.ts`
+
+This synchronous endpoint wraps `generateSceneContentFromInput` and returns raw slide elements without creating or persisting a scene. It loads stage metadata and outlines from server storage, so the client only needs to send the edited outline.
+
+- [ ] **Step 1: Write the failing test**
+
+```typescript
+// tests/api/scene-content-only.test.ts
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+
+// Mock storage backend
+vi.mock('@/lib/server/storage', () => ({
+  getStorageBackend: () => ({
+    loadStage: vi.fn().mockResolvedValue({
+      stage: { id: 'stage1', name: 'Test Stage', language: 'en-US' },
+    }),
+    loadOutlines: vi.fn().mockResolvedValue([
+      { id: 'o1', type: 'slide', title: 'Slide 1', description: 'Desc', keyPoints: [], order: 1 },
+    ]),
+  }),
+}));
+
+// Mock generateSceneContentFromInput
+vi.mock('@/lib/server/scene-content-generation', () => ({
+  generateSceneContentFromInput: vi.fn().mockResolvedValue({
+    content: { elements: [{ id: 'el1', type: 'text' }], background: undefined },
+    effectiveOutline: { id: 'o1', type: 'slide', title: 'Slide 1', description: 'Desc', keyPoints: [], order: 1 },
+    slideTheme: undefined,
+  }),
+}));
+
+vi.mock('@/lib/server/resolve-model', () => ({
+  resolveModelFromHeaders: vi.fn().mockResolvedValue({
+    model: {},
+    modelInfo: {},
+    modelString: 'test-model',
+  }),
+}));
+
+describe('POST /api/generate/scene-content-only', () => {
+  it('returns elements and background for a valid outline', async () => {
+    const { POST } = await import('@/app/api/generate/scene-content-only/route');
+    const req = new Request('http://localhost/api/generate/scene-content-only', {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json', 'x-model': 'test-model' },
+      body: JSON.stringify({
+        outline: { id: 'o1', type: 'slide', title: 'Slide 1', description: 'Desc', keyPoints: [], order: 1 },
+        stageId: 'stage1',
+      }),
+    });
+    const res = await POST(req as never);
+    const data = await res.json();
+    expect(data.success).toBe(true);
+    expect(data.data.elements).toBeDefined();
+  });
+
+  it('returns 400 when outline is missing', async () => {
+    const { POST } = await import('@/app/api/generate/scene-content-only/route');
+    const req = new Request('http://localhost/api/generate/scene-content-only', {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ stageId: 'stage1' }),
+    });
+    const res = await POST(req as never);
+    expect(res.status).toBe(400);
+  });
+});
+```
+
+- [ ] **Step 2: Run test to confirm it fails**
+
+```bash
+cd /home/ubuntu/dev/OpenMAIC && pnpm test -- tests/api/scene-content-only.test.ts --reporter=verbose
+```
+
+Expected: FAIL with "Cannot find module '@/app/api/generate/scene-content-only/route'"
+
+- [ ] **Step 3: Create the endpoint**
+
+```typescript
+// app/api/generate/scene-content-only/route.ts
+/**
+ * Synchronous slide content generation — returns raw PPTElements without persisting a scene.
+ * Used by the per-slide regeneration flow.
+ */
+import { NextRequest } from 'next/server';
+import { createLogger } from '@/lib/logger';
+import { apiError, apiSuccess } from '@/lib/server/api-response';
+import { generateSceneContentFromInput } from '@/lib/server/scene-content-generation';
+import { getStorageBackend } from '@/lib/server/storage';
+import { resolveModelFromHeaders } from '@/lib/server/resolve-model';
+import type { SceneOutline } from '@/lib/types/generation';
+import type { AgentInfo } from '@/lib/generation/generation-pipeline';
+
+const log = createLogger('SceneContentOnly API');
+
+export const maxDuration = 60;
+
+export async function POST(req: NextRequest) {
+  try {
+    const body = await req.json();
+    const { outline, stageId, agents, themeId } = body as {
+      outline: SceneOutline;
+      stageId: string;
+      agents?: AgentInfo[];
+      themeId?: string;
+    };
+
+    if (!outline) {
+      return apiError('MISSING_REQUIRED_FIELD', 400, 'outline is required');
+    }
+    if (!stageId) {
+      return apiError('MISSING_REQUIRED_FIELD', 400, 'stageId is required');
+    }
+
+    // Load stage metadata and outlines from server storage
+    const backend = getStorageBackend();
+    const [stageData, savedOutlines] = await Promise.all([
+      backend.loadStage(stageId),
+      backend.loadOutlines(stageId),
+    ]);
+
+    const allOutlines = savedOutlines ?? [outline];
+    const stageInfo = {
+      name: stageData?.stage.name ?? '',
+      description: stageData?.stage.description,
+      language: stageData?.stage.language,
+      style: stageData?.stage.style,
+      themeId: themeId,
+    };
+
+    const { modelString, apiKey, baseUrl, providerType } = {
+      modelString: req.headers.get('x-model') || undefined,
+      apiKey: req.headers.get('x-api-key') || undefined,
+      baseUrl: req.headers.get('x-base-url') || undefined,
+      providerType: req.headers.get('x-provider-type') || undefined,
+    };
+
+    const result = await generateSceneContentFromInput({
+      outline,
+      allOutlines,
+      stageId,
+      stageInfo,
+      agents,
+      modelConfig: { modelString, apiKey, baseUrl, providerType },
+    });
+
+    // Return only the slide content fields (elements + background)
+    const content = result.content as { elements?: unknown[]; background?: unknown };
+    return apiSuccess({
+      elements: content.elements ?? [],
+      background: content.background,
+    });
+  } catch (error) {
+    log.error('scene-content-only failed:', error);
+    return apiError('INTERNAL_ERROR', 500, error instanceof Error ? error.message : String(error));
+  }
+}
+```
+
+- [ ] **Step 4: Run test to confirm it passes**
+
+```bash
+cd /home/ubuntu/dev/OpenMAIC && pnpm test -- tests/api/scene-content-only.test.ts --reporter=verbose
+```
+
+Expected: PASS (2 tests)
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add app/api/generate/scene-content-only/route.ts tests/api/scene-content-only.test.ts
+git commit -m "feat: add scene-content-only endpoint for per-slide regeneration"
+```
+
+---
+
+## Task 2: API endpoint `POST /api/generate/media-prompt`
+
+**Files:**
+- Create: `app/api/generate/media-prompt/route.ts`
+- Test: `tests/api/media-prompt.test.ts`
+
+This lightweight endpoint uses a brief LLM call to generate a media generation prompt from a slide's indication text. Used by the dialog when the user switches to a media type not present in the original slide.
+
+- [ ] **Step 1: Write the failing test**
+
+```typescript
+// tests/api/media-prompt.test.ts
+import { describe, it, expect, vi } from 'vitest';
+
+vi.mock('@/lib/ai/llm', () => ({
+  callLLM: vi.fn().mockResolvedValue({ text: 'A diagram showing React components' }),
+}));
+
+vi.mock('@/lib/server/resolve-model', () => ({
+  resolveModelFromHeaders: vi.fn().mockResolvedValue({
+    model: {},
+    modelInfo: {},
+    modelString: 'test-model',
+  }),
+}));
+
+describe('POST /api/generate/media-prompt', () => {
+  it('returns a generated prompt string', async () => {
+    const { POST } = await import('@/app/api/generate/media-prompt/route');
+    const req = new Request('http://localhost/api/generate/media-prompt', {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json', 'x-model': 'test-model' },
+      body: JSON.stringify({
+        indicationText: 'React components: props, state, re-render',
+        mediaType: 'image',
+        language: 'en-US',
+      }),
+    });
+    const res = await POST(req as never);
+    const data = await res.json();
+    expect(data.success).toBe(true);
+    expect(typeof data.data.prompt).toBe('string');
+    expect(data.data.prompt.length).toBeGreaterThan(0);
+  });
+
+  it('returns 400 when indicationText is missing', async () => {
+    const { POST } = await import('@/app/api/generate/media-prompt/route');
+    const req = new Request('http://localhost/api/generate/media-prompt', {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ mediaType: 'image' }),
+    });
+    const res = await POST(req as never);
+    expect(res.status).toBe(400);
+  });
+});
+```
+
+- [ ] **Step 2: Run test to confirm it fails**
+
+```bash
+cd /home/ubuntu/dev/OpenMAIC && pnpm test -- tests/api/media-prompt.test.ts --reporter=verbose
+```
+
+Expected: FAIL with "Cannot find module"
+
+- [ ] **Step 3: Create the endpoint**
+
+```typescript
+// app/api/generate/media-prompt/route.ts
+/**
+ * Auto-generates a media generation prompt from a slide indication text.
+ * Used when the user picks a media type not present in the original slide.
+ */
+import { NextRequest } from 'next/server';
+import { createLogger } from '@/lib/logger';
+import { apiError, apiSuccess } from '@/lib/server/api-response';
+import { callLLM } from '@/lib/ai/llm';
+import { resolveModelFromHeaders } from '@/lib/server/resolve-model';
+
+const log = createLogger('MediaPrompt API');
+
+export const maxDuration = 30;
+
+export async function POST(req: NextRequest) {
+  try {
+    const body = await req.json();
+    const { indicationText, mediaType, language } = body as {
+      indicationText: string;
+      mediaType: 'image' | 'video';
+      language?: string;
+    };
+
+    if (!indicationText) {
+      return apiError('MISSING_REQUIRED_FIELD', 400, 'indicationText is required');
+    }
+    if (!mediaType || (mediaType !== 'image' && mediaType !== 'video')) {
+      return apiError('MISSING_REQUIRED_FIELD', 400, 'mediaType must be "image" or "video"');
+    }
+
+    const { model: languageModel } = await resolveModelFromHeaders(req);
+
+    const mediaLabel = mediaType === 'image' ? 'image' : 'short video loop';
+    const langHint = language ? ` The course language is ${language}.` : '';
+
+    const result = await callLLM(
+      {
+        model: languageModel,
+        system: `You are a visual media prompt writer. Given a slide description, write a concise prompt (1–2 sentences, max 30 words) for generating a ${mediaLabel} that visually represents the slide content. Respond with ONLY the prompt text — no quotes, no explanation.${langHint}`,
+        prompt: indicationText,
+        maxOutputTokens: 150,
+      },
+      'media-prompt',
+    );
+
+    const prompt = result.text.trim();
+    log.info(`Generated media prompt for ${mediaType}: "${prompt.slice(0, 60)}..."`);
+
+    return apiSuccess({ prompt });
+  } catch (error) {
+    log.error('media-prompt generation failed:', error);
+    return apiError('INTERNAL_ERROR', 500, error instanceof Error ? error.message : String(error));
+  }
+}
+```
+
+- [ ] **Step 4: Run test to confirm it passes**
+
+```bash
+cd /home/ubuntu/dev/OpenMAIC && pnpm test -- tests/api/media-prompt.test.ts --reporter=verbose
+```
+
+Expected: PASS (2 tests)
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add app/api/generate/media-prompt/route.ts tests/api/media-prompt.test.ts
+git commit -m "feat: add media-prompt endpoint for auto-generating media prompts"
+```
+
+---
+
+## Task 3: Export `generateAndStoreMedia` from media-orchestrator
+
+**Files:**
+- Modify: `lib/media/media-orchestrator.ts`
+
+The `generateSingleMedia` function already does everything needed for the hook (calls API, fetches blob, uploads to server, calls `markDone`). It just needs to be exported so the hook can call it directly.
+
+- [ ] **Step 1: Export the function**
+
+In `lib/media/media-orchestrator.ts`, change the internal function declaration from:
+
+```typescript
+async function generateSingleMedia(
+  req: MediaGenerationRequest,
+  stageId: string,
+  abortSignal?: AbortSignal,
+): Promise<void> {
+```
+
+to:
+
+```typescript
+export async function generateAndStoreMedia(
+  req: MediaGenerationRequest,
+  stageId: string,
+  abortSignal?: AbortSignal,
+): Promise<void> {
+```
+
+Then update the two internal callers in the same file (`generateMediaForOutlines` and `retryMediaTask`) to use the new name:
+
+In `generateMediaForOutlines`, change:
+```typescript
+    await generateSingleMedia(req, stageId, abortSignal);
+```
+to:
+```typescript
+    await generateAndStoreMedia(req, stageId, abortSignal);
+```
+
+In `retryMediaTask`, change:
+```typescript
+  await generateSingleMedia(
+```
+to:
+```typescript
+  await generateAndStoreMedia(
+```
+
+- [ ] **Step 2: Verify no TypeScript errors**
+
+```bash
+cd /home/ubuntu/dev/OpenMAIC && pnpm exec tsc --noEmit 2>&1 | grep "media-orchestrator" | head -10
+```
+
+Expected: No errors for this file.
+
+- [ ] **Step 3: Commit**
+
+```bash
+git add lib/media/media-orchestrator.ts
+git commit -m "refactor: export generateAndStoreMedia from media-orchestrator"
+```
+
+---
+
+## Task 4: `useSceneRegenerator` hook
+
+**Files:**
+- Create: `lib/hooks/use-scene-regenerator.ts`
+- Test: `tests/hooks/use-scene-regenerator.test.ts`
+
+This hook orchestrates the 4-step regeneration pipeline. Each step calls `store.updateScene()` so the user sees incremental progress.
+
+- [ ] **Step 1: Write the failing tests**
+
+```typescript
+// tests/hooks/use-scene-regenerator.test.ts
+import { describe, it, expect } from 'vitest';
+
+// Pure helper functions extracted for unit testing
+
+/** Serialise outline to indication textarea string */
+function outlineToIndication(description: string, keyPoints: string[]): string {
+  const bulletLines = keyPoints.map((k) => `• ${k}`).join('\n');
+  return keyPoints.length > 0 ? `${description}\n${bulletLines}` : description;
+}
+
+/** Parse indication textarea string back to description + keyPoints */
+function indicationToOutline(indication: string): { description: string; keyPoints: string[] } {
+  const lines = indication.split('\n');
+  const keyPoints: string[] = [];
+  const descLines: string[] = [];
+  for (const line of lines) {
+    if (line.startsWith('• ')) {
+      keyPoints.push(line.slice(2).trim());
+    } else {
+      descLines.push(line);
+    }
+  }
+  return { description: descLines.join('\n').trim(), keyPoints };
+}
+
+/** Build outline.mediaGenerations from hook params */
+function buildMediaGenerations(
+  mediaType: 'none' | 'image' | 'video',
+  mediaPrompt?: string,
+) {
+  if (mediaType === 'none') return [];
+  const elementId = mediaType === 'image' ? 'gen_img_1' : 'gen_vid_1';
+  return [{ elementId, type: mediaType, prompt: mediaPrompt ?? '' }];
+}
+
+/** Split audio override text by \n\n and map to speech action texts */
+function applyAudioOverride(
+  actions: Array<{ type: string; text?: string; id: string }>,
+  audioOverride: string,
+): Array<{ type: string; text?: string; id: string }> {
+  const segments = audioOverride
+    .split('\n\n')
+    .map((s) => s.trim())
+    .filter(Boolean);
+  let segIdx = 0;
+  return actions.map((a) => {
+    if (a.type === 'speech' && a.text !== undefined && segIdx < segments.length) {
+      return { ...a, text: segments[segIdx++] };
+    }
+    return a;
+  });
+}
+
+describe('outlineToIndication', () => {
+  it('joins description and key points with bullets', () => {
+    const result = outlineToIndication('Intro to React', ['components', 'props']);
+    expect(result).toBe('Intro to React\n• components\n• props');
+  });
+
+  it('returns only description when no key points', () => {
+    expect(outlineToIndication('Just a description', [])).toBe('Just a description');
+  });
+});
+
+describe('indicationToOutline', () => {
+  it('parses bullets as keyPoints and plain lines as description', () => {
+    const result = indicationToOutline('Intro to React\n• components\n• props');
+    expect(result.description).toBe('Intro to React');
+    expect(result.keyPoints).toEqual(['components', 'props']);
+  });
+});
+
+describe('buildMediaGenerations', () => {
+  it('returns empty array for none', () => {
+    expect(buildMediaGenerations('none')).toEqual([]);
+  });
+
+  it('returns image entry with gen_img_1 elementId', () => {
+    const result = buildMediaGenerations('image', 'A React diagram');
+    expect(result[0].elementId).toBe('gen_img_1');
+    expect(result[0].type).toBe('image');
+    expect(result[0].prompt).toBe('A React diagram');
+  });
+
+  it('returns video entry with gen_vid_1 elementId', () => {
+    const result = buildMediaGenerations('video', 'Animation showing React');
+    expect(result[0].elementId).toBe('gen_vid_1');
+    expect(result[0].type).toBe('video');
+  });
+});
+
+describe('applyAudioOverride', () => {
+  it('maps segments to speech actions by index', () => {
+    const actions = [
+      { type: 'spotlight', id: 's1' },
+      { type: 'speech', text: 'original 1', id: 'sp1' },
+      { type: 'speech', text: 'original 2', id: 'sp2' },
+    ];
+    const result = applyAudioOverride(actions, 'new segment 1\n\nnew segment 2');
+    expect(result[1].text).toBe('new segment 1');
+    expect(result[2].text).toBe('new segment 2');
+  });
+
+  it('keeps AI text when user provides fewer segments than actions', () => {
+    const actions = [
+      { type: 'speech', text: 'original 1', id: 'sp1' },
+      { type: 'speech', text: 'original 2', id: 'sp2' },
+    ];
+    const result = applyAudioOverride(actions, 'only one segment');
+    expect(result[0].text).toBe('only one segment');
+    expect(result[1].text).toBe('original 2');
+  });
+});
+```
+
+- [ ] **Step 2: Run tests to confirm they fail**
+
+```bash
+cd /home/ubuntu/dev/OpenMAIC && pnpm test -- tests/hooks/use-scene-regenerator.test.ts --reporter=verbose
+```
+
+Expected: FAIL — functions not defined yet.
+
+- [ ] **Step 3: Create the hook (includes the tested pure helpers as exported utilities)**
+
+```typescript
+// lib/hooks/use-scene-regenerator.ts
+'use client';
+
+import { useRef, useState, useCallback } from 'react';
+import { useStageStore } from '@/lib/store/stage';
+import { useMediaGenerationStore } from '@/lib/store/media-generation';
+import { useSettingsStore } from '@/lib/store/settings';
+import { getCurrentModelConfig } from '@/lib/utils/model-config';
+import { generateAndStoreMedia } from '@/lib/media/media-orchestrator';
+import { generateAndStoreTTS } from '@/lib/audio/generate-and-store-tts';
+import { splitLongSpeechActions } from '@/lib/audio/tts-utils';
+import { createLogger } from '@/lib/logger';
+import type { SceneOutline } from '@/lib/types/generation';
+import type { Action, SpeechAction } from '@/lib/types/action';
+
+const log = createLogger('SceneRegenerator');
+
+// ── Pure helpers (also used by RegenerateSlideDialog) ──
+
+/** Serialise an outline's indication into the dialog textarea format */
+export function outlineToIndication(description: string, keyPoints: string[]): string {
+  const bulletLines = keyPoints.map((k) => `• ${k}`).join('\n');
+  return keyPoints.length > 0 ? `${description}\n${bulletLines}` : description;
+}
+
+/** Parse a textarea indication string back to description + keyPoints */
+export function indicationToOutline(indication: string): {
+  description: string;
+  keyPoints: string[];
+} {
+  const lines = indication.split('\n');
+  const keyPoints: string[] = [];
+  const descLines: string[] = [];
+  for (const line of lines) {
+    if (line.startsWith('• ')) {
+      keyPoints.push(line.slice(2).trim());
+    } else {
+      descLines.push(line);
+    }
+  }
+  return { description: descLines.join('\n').trim(), keyPoints };
+}
+
+/** Build outline.mediaGenerations from the user's media selection */
+export function buildMediaGenerations(
+  mediaType: 'none' | 'image' | 'video',
+  mediaPrompt?: string,
+): SceneOutline['mediaGenerations'] {
+  if (mediaType === 'none') return [];
+  const elementId = mediaType === 'image' ? 'gen_img_1' : 'gen_vid_1';
+  return [{ elementId, type: mediaType, prompt: mediaPrompt ?? '' }];
+}
+
+/** Override speech action texts with user-edited segments (split by \n\n, 1:1 by index) */
+export function applyAudioOverride(actions: Action[], audioOverride: string): Action[] {
+  const segments = audioOverride
+    .split('\n\n')
+    .map((s) => s.trim())
+    .filter(Boolean);
+  let segIdx = 0;
+  return actions.map((a) => {
+    if (a.type === 'speech' && segIdx < segments.length) {
+      return { ...a, text: segments[segIdx++] } as SpeechAction;
+    }
+    return a;
+  });
+}
+
+// ── Hook types ──
+
+export interface RegenerateParams {
+  outline: SceneOutline;
+  audioTextOverride: string;
+  mediaType: 'none' | 'image' | 'video';
+  mediaPrompt?: string;
+}
+
+export type RegenerateProgress = 'idle' | 'content' | 'audio' | 'media' | 'done' | 'error';
+
+export interface UseSceneRegeneratorReturn {
+  regenerate: (sceneId: string, params: RegenerateParams) => Promise<void>;
+  progress: RegenerateProgress;
+  errorStep?: 'content' | 'audio' | 'media';
+  cancel: () => void;
+}
+
+// ── Hook ──
+
+function getApiHeaders(): HeadersInit {
+  const config = getCurrentModelConfig();
+  return {
+    'Content-Type': 'application/json',
+    'x-model': config.modelString || '',
+    'x-provider-type': config.providerType || '',
+  };
+}
+
+export function useSceneRegenerator(): UseSceneRegeneratorReturn {
+  const abortRef = useRef<AbortController | null>(null);
+  const [progress, setProgress] = useState<RegenerateProgress>('idle');
+  const [errorStep, setErrorStep] = useState<'content' | 'audio' | 'media' | undefined>();
+
+  const regenerate = useCallback(async (sceneId: string, params: RegenerateParams) => {
+    abortRef.current?.abort();
+    const ctrl = new AbortController();
+    abortRef.current = ctrl;
+    const signal = ctrl.signal;
+
+    setProgress('content');
+    setErrorStep(undefined);
+
+    const store = useStageStore.getState();
+    const stageId = store.stage?.id;
+    const allOutlines = store.outlines;
+
+    if (!stageId) {
+      log.error('Cannot regenerate: no active stage');
+      setProgress('error');
+      setErrorStep('content');
+      return;
+    }
+
+    // Pre-step: set outline.mediaGenerations based on user's media selection
+    const outline: SceneOutline = {
+      ...params.outline,
+      mediaGenerations: buildMediaGenerations(params.mediaType, params.mediaPrompt),
+    };
+
+    // ── Step 1a: Generate slide content ──
+    let contentData: { elements: unknown[]; background?: unknown };
+    try {
+      const contentRes = await fetch('/api/generate/scene-content-only', {
+        method: 'POST',
+        headers: getApiHeaders(),
+        body: JSON.stringify({ outline, stageId }),
+        signal,
+      });
+      const json = await contentRes.json();
+      if (!contentRes.ok || !json.success) {
+        throw new Error(json.error || `HTTP ${contentRes.status}`);
+      }
+      contentData = json.data;
+    } catch (err) {
+      if (signal.aborted) return;
+      log.error('Step 1 (content) failed:', err);
+      setProgress('error');
+      setErrorStep('content');
+      return;
+    }
+
+    if (signal.aborted) return;
+
+    // ── Step 1b: Generate scene actions ──
+    let newActions: Action[];
+    let newContent: unknown;
+    try {
+      const actionsRes = await fetch('/api/generate/scene-actions', {
+        method: 'POST',
+        headers: getApiHeaders(),
+        body: JSON.stringify({
+          outline,
+          allOutlines,
+          content: contentData,
+          stageId,
+        }),
+        signal,
+      });
+      const json = await actionsRes.json();
+      if (!actionsRes.ok || !json.success || !json.scene) {
+        throw new Error(json.error || `HTTP ${actionsRes.status}`);
+      }
+      newActions = json.scene.actions ?? [];
+      newContent = json.scene.content;
+    } catch (err) {
+      if (signal.aborted) return;
+      log.error('Step 1 (actions) failed:', err);
+      setProgress('error');
+      setErrorStep('content');
+      return;
+    }
+
+    if (signal.aborted) return;
+
+    // Immediately show new slide (without audio)
+    store.updateScene(sceneId, { content: newContent as never, actions: newActions });
+
+    // ── Step 2: Audio ──
+    setProgress('audio');
+
+    // Apply user audio text override and split long actions
+    const overriddenActions = applyAudioOverride(newActions, params.audioTextOverride);
+    const providerId = useSettingsStore.getState().ttsProviderId;
+    const splitActions = splitLongSpeechActions(overriddenActions, providerId);
+
+    for (const action of splitActions) {
+      if (signal.aborted) return;
+      if (action.type !== 'speech' || !(action as SpeechAction).text) continue;
+      const speechAction = action as SpeechAction;
+      const audioId = `tts_${speechAction.id}`;
+      speechAction.audioId = audioId;
+      try {
+        const url = await generateAndStoreTTS(audioId, speechAction.text, signal);
+        if (url) speechAction.audioUrl = url;
+      } catch (err) {
+        if (signal.aborted) return;
+        log.warn('TTS failed for action', speechAction.id, ':', err);
+        // Non-fatal: continue with remaining actions, slide is still visible
+      }
+      store.updateScene(sceneId, { actions: [...splitActions] });
+    }
+
+    // ── Step 3: Media ──
+    if (params.mediaType !== 'none' && params.mediaPrompt) {
+      if (signal.aborted) return;
+      setProgress('media');
+      const elementId = params.mediaType === 'image' ? 'gen_img_1' : 'gen_vid_1';
+      const req = {
+        elementId,
+        type: params.mediaType as 'image' | 'video',
+        prompt: params.mediaPrompt,
+      };
+      useMediaGenerationStore.getState().enqueueTasks(stageId, [req]);
+      try {
+        await generateAndStoreMedia(req, stageId, signal);
+      } catch (err) {
+        if (signal.aborted) return;
+        log.warn('Media generation failed:', err);
+        // Non-fatal: useMediaGenerationStore shows error state with retry option
+      }
+    }
+
+    if (signal.aborted) return;
+
+    // ── Step 4: Outline sync ──
+    const updatedOutlines = allOutlines.map((o) => (o.order === outline.order ? outline : o));
+    store.setOutlines(updatedOutlines);
+
+    setProgress('done');
+  }, []);
+
+  const cancel = useCallback(() => {
+    abortRef.current?.abort();
+    setProgress('idle');
+    setErrorStep(undefined);
+  }, []);
+
+  return { regenerate, progress, errorStep, cancel };
+}
+```
+
+- [ ] **Step 4: Update the test to import from the hook**
+
+Update `tests/hooks/use-scene-regenerator.test.ts` — replace the inline function declarations with imports:
+
+```typescript
+// tests/hooks/use-scene-regenerator.test.ts
+import { describe, it, expect } from 'vitest';
+import {
+  outlineToIndication,
+  indicationToOutline,
+  buildMediaGenerations,
+  applyAudioOverride,
+} from '@/lib/hooks/use-scene-regenerator';
+
+// ... (keep all the describe blocks exactly as written in Step 1, remove the inline function declarations)
+```
+
+- [ ] **Step 5: Run tests to confirm they pass**
+
+```bash
+cd /home/ubuntu/dev/OpenMAIC && pnpm test -- tests/hooks/use-scene-regenerator.test.ts --reporter=verbose
+```
+
+Expected: PASS (7 tests)
+
+- [ ] **Step 6: Commit**
+
+```bash
+git add lib/hooks/use-scene-regenerator.ts tests/hooks/use-scene-regenerator.test.ts
+git commit -m "feat: add useSceneRegenerator hook with 4-step incremental pipeline"
+```
+
+---
+
+## Task 5: `RegenerateSlideDialog` component
+
+**Files:**
+- Create: `components/classroom/regenerate-slide-dialog.tsx`
+
+This dialog pre-loads the indication, audio text, and media type from the current outline and scene. When the user selects a media type not in the original slide, it calls `POST /api/generate/media-prompt` to auto-generate a prompt.
+
+- [ ] **Step 1: Create the component**
+
+```typescript
+// components/classroom/regenerate-slide-dialog.tsx
+'use client';
+
+import { useState, useEffect, useCallback } from 'react';
+import {
+  Dialog,
+  DialogContent,
+  DialogHeader,
+  DialogTitle,
+  DialogFooter,
+} from '@/components/ui/dialog';
+import { Button } from '@/components/ui/button';
+import { Textarea } from '@/components/ui/textarea';
+import { Label } from '@/components/ui/label';
+import { RadioGroup, RadioGroupItem } from '@/components/ui/radio-group';
+import { useI18n } from '@/lib/hooks/use-i18n';
+import { outlineToIndication, indicationToOutline } from '@/lib/hooks/use-scene-regenerator';
+import { getCurrentModelConfig } from '@/lib/utils/model-config';
+import type { Scene } from '@/lib/types/stage';
+import type { SceneOutline } from '@/lib/types/generation';
+import type { SpeechAction } from '@/lib/types/action';
+import type { RegenerateParams } from '@/lib/hooks/use-scene-regenerator';
+
+export interface RegenerateFormValues {
+  indication: string;
+  audioText: string;
+  mediaType: 'none' | 'image' | 'video';
+  mediaPrompt: string;
+}
+
+interface RegenerateSlideDialogProps {
+  open: boolean;
+  scene: Scene;
+  outline: SceneOutline;
+  initialValues?: RegenerateFormValues;
+  onRegenerate: (params: RegenerateParams) => void;
+  onClose: () => void;
+}
+
+function sceneToAudioText(scene: Scene): string {
+  return (scene.actions ?? [])
+    .filter((a): a is SpeechAction => a.type === 'speech' && !!a.text)
+    .map((a) => a.text)
+    .join('\n\n');
+}
+
+function outlineToMediaType(outline: SceneOutline): 'none' | 'image' | 'video' {
+  const generations = outline.mediaGenerations ?? [];
+  if (generations.some((g) => g.type === 'video')) return 'video';
+  if (generations.some((g) => g.type === 'image')) return 'image';
+  return 'none';
+}
+
+function outlineToMediaPrompt(outline: SceneOutline, mediaType: 'none' | 'image' | 'video'): string {
+  if (mediaType === 'none') return '';
+  const entry = (outline.mediaGenerations ?? []).find((g) => g.type === mediaType);
+  return entry?.prompt ?? '';
+}
+
+export function RegenerateSlideDialog({
+  open,
+  scene,
+  outline,
+  initialValues,
+  onRegenerate,
+  onClose,
+}: RegenerateSlideDialogProps) {
+  const { t } = useI18n();
+
+  const [indication, setIndication] = useState('');
+  const [audioText, setAudioText] = useState('');
+  const [mediaType, setMediaType] = useState<'none' | 'image' | 'video'>('none');
+  const [mediaPrompt, setMediaPrompt] = useState('');
+  const [isGeneratingPrompt, setIsGeneratingPrompt] = useState(false);
+
+  // Initialise form values on open
+  useEffect(() => {
+    if (!open) return;
+    if (initialValues) {
+      setIndication(initialValues.indication);
+      setAudioText(initialValues.audioText);
+      setMediaType(initialValues.mediaType);
+      setMediaPrompt(initialValues.mediaPrompt);
+    } else {
+      setIndication(outlineToIndication(outline.description, outline.keyPoints));
+      setAudioText(sceneToAudioText(scene));
+      const mt = outlineToMediaType(outline);
+      setMediaType(mt);
+      setMediaPrompt(outlineToMediaPrompt(outline, mt));
+    }
+  }, [open, outline, scene, initialValues]);
+
+  const generatePromptForType = useCallback(
+    async (type: 'image' | 'video') => {
+      setIsGeneratingPrompt(true);
+      setMediaPrompt('');
+      try {
+        const config = getCurrentModelConfig();
+        const res = await fetch('/api/generate/media-prompt', {
+          method: 'POST',
+          headers: {
+            'Content-Type': 'application/json',
+            'x-model': config.modelString || '',
+            'x-provider-type': config.providerType || '',
+          },
+          body: JSON.stringify({
+            indicationText: indication,
+            mediaType: type,
+            language: outline.language,
+          }),
+        });
+        const json = await res.json();
+        if (json.success && json.data?.prompt) {
+          setMediaPrompt(json.data.prompt);
+        }
+      } catch {
+        // Prompt stays empty; user can type it manually
+      } finally {
+        setIsGeneratingPrompt(false);
+      }
+    },
+    [indication, outline.language],
+  );
+
+  const handleMediaTypeChange = useCallback(
+    (value: 'none' | 'image' | 'video') => {
+      setMediaType(value);
+      if (value === 'none') {
+        setMediaPrompt('');
+        return;
+      }
+      // Check if original outline already has a prompt for this type
+      const existingPrompt = outlineToMediaPrompt(outline, value);
+      if (existingPrompt) {
+        setMediaPrompt(existingPrompt);
+      } else {
+        generatePromptForType(value);
+      }
+    },
+    [outline, generatePromptForType],
+  );
+
+  const handleSubmit = () => {
+    const { description, keyPoints } = indicationToOutline(indication);
+    const updatedOutline: SceneOutline = {
+      ...outline,
+      description,
+      keyPoints,
+    };
+    onRegenerate({
+      outline: updatedOutline,
+      audioTextOverride: audioText,
+      mediaType,
+      mediaPrompt: mediaType !== 'none' ? mediaPrompt : undefined,
+    });
+    onClose();
+  };
+
+  const isSubmitDisabled = isGeneratingPrompt || (mediaType !== 'none' && !mediaPrompt.trim());
+
+  return (
+    <Dialog open={open} onOpenChange={(o) => !o && onClose()}>
+      <DialogContent className="max-w-lg max-h-[90vh] flex flex-col overflow-hidden">
+        <DialogHeader>
+          <DialogTitle className="text-purple-700 dark:text-purple-300">
+            ↺ {t('stage.regen.dialogTitle')} — {scene.title}
+          </DialogTitle>
+        </DialogHeader>
+
+        <div className="flex-1 overflow-y-auto space-y-4 px-1 py-2">
+          {/* Indication */}
+          <div className="space-y-1.5">
+            <Label className="text-xs font-semibold uppercase tracking-wide text-muted-foreground">
+              {t('stage.regen.indication')}
+            </Label>
+            <Textarea
+              value={indication}
+              onChange={(e) => setIndication(e.target.value)}
+              rows={4}
+              className="resize-none text-sm"
+              placeholder={t('stage.regen.indicationPlaceholder')}
+            />
+          </div>
+
+          {/* Audio text */}
+          <div className="space-y-1.5">
+            <Label className="text-xs font-semibold uppercase tracking-wide text-muted-foreground">
+              {t('stage.regen.audioText')}
+            </Label>
+            <Textarea
+              value={audioText}
+              onChange={(e) => setAudioText(e.target.value)}
+              rows={6}
+              className="resize-none text-sm"
+              placeholder={t('stage.regen.audioTextPlaceholder')}
+            />
+          </div>
+
+          {/* Media selector */}
+          <div className="space-y-2">
+            <Label className="text-xs font-semibold uppercase tracking-wide text-muted-foreground">
+              {t('stage.regen.media')}
+            </Label>
+            <RadioGroup
+              value={mediaType}
+              onValueChange={handleMediaTypeChange as (v: string) => void}
+              className="flex gap-3"
+            >
+              {(['none', 'image', 'video'] as const).map((opt) => (
+                <div key={opt} className="flex items-center gap-1.5">
+                  <RadioGroupItem value={opt} id={`media-${opt}`} />
+                  <Label htmlFor={`media-${opt}`} className="text-sm cursor-pointer capitalize">
+                    {t(`stage.regen.media${opt.charAt(0).toUpperCase() + opt.slice(1)}`)}
+                  </Label>
+                </div>
+              ))}
+            </RadioGroup>
+
+            {mediaType !== 'none' && (
+              <div className="space-y-1">
+                {isGeneratingPrompt ? (
+                  <p className="text-xs text-blue-500 dark:text-blue-400 animate-pulse">
+                    ✨ {t('stage.regen.generatingPrompt')}
+                  </p>
+                ) : (
+                  <p className="text-xs text-muted-foreground">
+                    {outlineToMediaPrompt(outline, mediaType)
+                      ? t('stage.regen.promptOriginal')
+                      : t('stage.regen.promptAutoGenerated')}
+                  </p>
+                )}
+                <Textarea
+                  value={mediaPrompt}
+                  onChange={(e) => setMediaPrompt(e.target.value)}
+                  rows={3}
+                  disabled={isGeneratingPrompt}
+                  className="resize-none text-sm"
+                  placeholder={t('stage.regen.mediaPromptPlaceholder')}
+                />
+              </div>
+            )}
+          </div>
+        </div>
+
+        <DialogFooter className="pt-2">
+          <Button variant="ghost" onClick={onClose}>
+            {t('stage.regen.cancel')}
+          </Button>
+          <Button
+            onClick={handleSubmit}
+            disabled={isSubmitDisabled}
+            className="bg-purple-600 hover:bg-purple-700 text-white"
+          >
+            ↺ {t('stage.regen.regenerate')}
+          </Button>
+        </DialogFooter>
+      </DialogContent>
+    </Dialog>
+  );
+}
+```
+
+- [ ] **Step 2: Add i18n strings**
+
+In `lib/i18n/stage.ts`, add these keys to all three locales (`zh-CN`, `en-US`, `ca`). Find the existing `stage` section and add inside it:
+
+**For `en-US`:**
+```typescript
+'stage.regen.dialogTitle': 'Regenerate',
+'stage.regen.indication': 'Indication',
+'stage.regen.indicationPlaceholder': 'Describe what this slide should cover…',
+'stage.regen.audioText': 'Audio text',
+'stage.regen.audioTextPlaceholder': 'Narration text for this slide…',
+'stage.regen.media': 'Media',
+'stage.regen.mediaNone': 'None',
+'stage.regen.mediaImage': 'Image',
+'stage.regen.mediaVideo': 'Video',
+'stage.regen.generatingPrompt': 'Generating prompt…',
+'stage.regen.promptOriginal': 'Original prompt loaded. You can modify it.',
+'stage.regen.promptAutoGenerated': 'Auto-generated prompt. Edit if needed.',
+'stage.regen.mediaPromptPlaceholder': 'Describe the image or video…',
+'stage.regen.cancel': 'Cancel',
+'stage.regen.regenerate': 'Regenerate',
+'stage.regen.reviewBar': 'Regenerated version — pending acceptance',
+'stage.regen.accept': 'Accept',
+'stage.regen.undo': 'Undo',
+'stage.regen.editAgain': 'Edit again',
+'stage.regen.confirmTitle': 'Keep new version?',
+'stage.regen.confirmBody': 'Slide "{title}" has a regenerated version pending acceptance. If you switch slides without accepting, the new version will be discarded.',
+'stage.regen.confirmKeep': 'Yes, keep',
+'stage.regen.confirmDiscard': 'Discard',
+'stage.regen.buttonLabel': '↺ Regen.',
+```
+
+**For `ca`:**
+```typescript
+'stage.regen.dialogTitle': 'Regenerar',
+'stage.regen.indication': 'Indicació',
+'stage.regen.indicationPlaceholder': 'Descriu el que hauria de cobrir aquesta slide…',
+'stage.regen.audioText': 'Text àudio',
+'stage.regen.audioTextPlaceholder': 'Text de narració per a aquesta slide…',
+'stage.regen.media': 'Media',
+'stage.regen.mediaNone': 'Cap',
+'stage.regen.mediaImage': 'Imatge',
+'stage.regen.mediaVideo': 'Vídeo',
+'stage.regen.generatingPrompt': 'Generant prompt…',
+'stage.regen.promptOriginal': 'Prompt original recuperat. Pots modificar-lo.',
+'stage.regen.promptAutoGenerated': 'Prompt generat automàticament. Edita\'l si cal.',
+'stage.regen.mediaPromptPlaceholder': 'Descriu la imatge o el vídeo…',
+'stage.regen.cancel': 'Cancel·lar',
+'stage.regen.regenerate': 'Regenerar',
+'stage.regen.reviewBar': 'Versió regenerada — pendent d\'acceptar',
+'stage.regen.accept': 'Acceptar',
+'stage.regen.undo': 'Desfer',
+'stage.regen.editAgain': 'Tornar a editar',
+'stage.regen.confirmTitle': 'Conservar la nova versió?',
+'stage.regen.confirmBody': 'Slide "{title}" té una versió regenerada pendent d\'acceptar. Si canvies de slide sense acceptar, la nova versió es descartarà.',
+'stage.regen.confirmKeep': 'Sí, conservar',
+'stage.regen.confirmDiscard': 'Descartar',
+'stage.regen.buttonLabel': '↺ Regen.',
+```
+
+**For `zh-CN`:**
+```typescript
+'stage.regen.dialogTitle': '重新生成',
+'stage.regen.indication': '说明',
+'stage.regen.indicationPlaceholder': '描述此幻灯片应涵盖的内容…',
+'stage.regen.audioText': '音频文本',
+'stage.regen.audioTextPlaceholder': '此幻灯片的旁白文本…',
+'stage.regen.media': '媒体',
+'stage.regen.mediaNone': '无',
+'stage.regen.mediaImage': '图片',
+'stage.regen.mediaVideo': '视频',
+'stage.regen.generatingPrompt': '正在生成提示词…',
+'stage.regen.promptOriginal': '已加载原始提示词，可以修改。',
+'stage.regen.promptAutoGenerated': '自动生成的提示词，可按需编辑。',
+'stage.regen.mediaPromptPlaceholder': '描述图片或视频…',
+'stage.regen.cancel': '取消',
+'stage.regen.regenerate': '重新生成',
+'stage.regen.reviewBar': '已重新生成 — 等待确认',
+'stage.regen.accept': '接受',
+'stage.regen.undo': '撤销',
+'stage.regen.editAgain': '重新编辑',
+'stage.regen.confirmTitle': '保留新版本？',
+'stage.regen.confirmBody': '幻灯片"{title}"有一个待确认的重新生成版本。如果切换幻灯片而不接受，新版本将被丢弃。',
+'stage.regen.confirmKeep': '是，保留',
+'stage.regen.confirmDiscard': '放弃',
+'stage.regen.buttonLabel': '↺ 重新生成',
+```
+
+- [ ] **Step 3: Verify TypeScript compiles**
+
+```bash
+cd /home/ubuntu/dev/OpenMAIC && pnpm exec tsc --noEmit 2>&1 | grep "regenerate-slide-dialog" | head -10
+```
+
+Expected: No errors for this file.
+
+- [ ] **Step 4: Commit**
+
+```bash
+git add components/classroom/regenerate-slide-dialog.tsx lib/i18n/stage.ts
+git commit -m "feat: add RegenerateSlideDialog component with media auto-prompt"
+```
+
+---
+
+## Task 6: Add ↺ Regen. button to `SceneSidebar`
+
+**Files:**
+- Modify: `components/stage/scene-sidebar.tsx`
+
+The button is shown only when the active scene is a slide and `regenState === 'idle'`. It is hidden (not disabled) during regeneration to prevent double-triggering.
+
+- [ ] **Step 1: Add new props to `SceneSidebarProps`**
+
+In `components/stage/scene-sidebar.tsx`, update the `SceneSidebarProps` interface at line 22:
+
+```typescript
+interface SceneSidebarProps {
+  readonly collapsed: boolean;
+  readonly onCollapseChange: (collapsed: boolean) => void;
+  readonly onSceneSelect?: (sceneId: string) => void;
+  readonly onRetryOutline?: (outlineId: string) => Promise<void>;
+  readonly regenState?: 'idle' | 'regenerating' | 'review';
+  readonly onRegenerateClick?: () => void;
+}
+```
+
+- [ ] **Step 2: Destructure new props in the component function**
+
+At line 33, update the destructured props:
+
+```typescript
+export function SceneSidebar({
+  collapsed,
+  onCollapseChange,
+  onSceneSelect,
+  onRetryOutline,
+  regenState = 'idle',
+  onRegenerateClick,
+}: SceneSidebarProps) {
+```
+
+- [ ] **Step 3: Add the button below the active scene thumbnail**
+
+After the closing `</div>` of the thumbnail area (the `<div className="relative aspect-video...">` block, around line 321), add the regen button:
+
+```tsx
+{/* ↺ Regen. button — only for active slide scenes when idle */}
+{isActive && isSlide && regenState === 'idle' && onRegenerateClick && (
+  <button
+    onClick={(e) => {
+      e.stopPropagation();
+      onRegenerateClick();
+    }}
+    className="w-full mt-1 py-0.5 px-2 text-[10px] font-semibold rounded border border-purple-200 dark:border-purple-700 text-purple-600 dark:text-purple-400 hover:bg-purple-50 dark:hover:bg-purple-900/30 transition-colors flex items-center justify-center gap-1"
+  >
+    ↺ {t('stage.regen.buttonLabel')}
+  </button>
+)}
+```
+
+- [ ] **Step 4: Verify TypeScript compiles**
+
+```bash
+cd /home/ubuntu/dev/OpenMAIC && pnpm exec tsc --noEmit 2>&1 | grep "scene-sidebar" | head -5
+```
+
+Expected: No errors.
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add components/stage/scene-sidebar.tsx
+git commit -m "feat: add regen button to SceneSidebar for active slide scenes"
+```
+
+---
+
+## Task 7: State machine + review bar in `Stage`
+
+**Files:**
+- Modify: `components/stage.tsx`
+
+This is the main wiring task. It adds the regen state machine, backup logic, review bar, second AlertDialog, and integrates the dialog + hook.
+
+- [ ] **Step 1: Add imports at the top of `components/stage.tsx`**
+
+After the existing imports, add:
+
+```typescript
+import { useSceneRegenerator } from '@/lib/hooks/use-scene-regenerator';
+import { RegenerateSlideDialog, type RegenerateFormValues } from '@/components/classroom/regenerate-slide-dialog';
+import type { Scene } from '@/lib/types/stage';
+```
+
+(Note: `Scene` may already be imported — check and add only if missing.)
+
+- [ ] **Step 2: Add regen state variables after the existing `useState` declarations (around line 100)**
+
+```typescript
+// Regenerate-slide state machine
+type RegenState = 'idle' | 'dialog_open' | 'regenerating' | 'review';
+const [regenState, setRegenState] = useState<RegenState>('idle');
+const [backupScene, setBackupScene] = useState<Scene | null>(null);
+const [lastRegenValues, setLastRegenValues] = useState<RegenerateFormValues | null>(null);
+const [pendingRegenSceneId, setPendingRegenSceneId] = useState<string | null>(null);
+```
+
+- [ ] **Step 3: Add `useSceneRegenerator` hook call after the existing hook calls (around line 135)**
+
+```typescript
+const sceneRegenerator = useSceneRegenerator();
+```
+
+- [ ] **Step 4: Add regen handler callbacks before `gatedSceneSwitch` (around line 660)**
+
+```typescript
+/** Open the regeneration dialog for the current scene */
+const openRegenerateDialog = useCallback(() => {
+  if (!currentScene || currentScene.type !== 'slide') return;
+  setRegenState('dialog_open');
+}, [currentScene]);
+
+/** Called when the dialog submits — starts the regeneration pipeline */
+const handleRegenerate = useCallback(
+  async (params: import('@/lib/hooks/use-scene-regenerator').RegenerateParams) => {
+    if (!currentScene) return;
+    // Store values for "Tornar a editar"
+    const { outlineToIndication } = await import('@/lib/hooks/use-scene-regenerator');
+    const outline = useStageStore.getState().outlines.find((o) => o.order === currentScene.order);
+    setLastRegenValues({
+      indication: outlineToIndication(params.outline.description, params.outline.keyPoints),
+      audioText: params.audioTextOverride,
+      mediaType: params.mediaType,
+      mediaPrompt: params.mediaPrompt ?? '',
+    });
+    // Backup current scene before mutating
+    setBackupScene({ ...currentScene });
+    setRegenState('regenerating');
+    await sceneRegenerator.regenerate(currentScene.id, params);
+    setRegenState('review');
+  },
+  [currentScene, sceneRegenerator],
+);
+
+/** Accept the new version: clear backup, return to idle */
+const handleRegenAccept = useCallback(() => {
+  setBackupScene(null);
+  setLastRegenValues(null);
+  setRegenState('idle');
+}, []);
+
+/** Undo: restore backup scene to store, return to idle */
+const handleRegenUndo = useCallback(() => {
+  if (backupScene && currentScene) {
+    useStageStore.getState().updateScene(currentScene.id, {
+      content: backupScene.content,
+      actions: backupScene.actions,
+    });
+  }
+  setBackupScene(null);
+  setLastRegenValues(null);
+  setRegenState('idle');
+}, [backupScene, currentScene]);
+
+/** Reopen dialog with previously entered values */
+const handleRegenEditAgain = useCallback(() => {
+  setRegenState('dialog_open');
+}, []);
+```
+
+- [ ] **Step 5: Update `gatedSceneSwitch` to intercept review state**
+
+Find the existing `gatedSceneSwitch` callback (around line 668) and extend it to also check `regenState === 'review'`:
+
+```typescript
+const gatedSceneSwitch = useCallback(
+  (targetSceneId: string): boolean => {
+    if (targetSceneId === currentSceneId) return false;
+    if (isTopicActive) {
+      setPendingSceneId(targetSceneId);
+      return false;
+    }
+    // If a regenerated version is pending review, show regen confirm dialog
+    if (regenState === 'review') {
+      setPendingRegenSceneId(targetSceneId);
+      return false;
+    }
+    setCurrentSceneId(targetSceneId);
+    return true;
+  },
+  [currentSceneId, isTopicActive, regenState, setCurrentSceneId],
+);
+```
+
+- [ ] **Step 6: Add regen confirm handlers**
+
+```typescript
+/** User chose "Sí, conservar" in regen confirm modal */
+const confirmRegenKeep = useCallback(() => {
+  if (!pendingRegenSceneId) return;
+  setBackupScene(null);
+  setLastRegenValues(null);
+  setRegenState('idle');
+  setCurrentSceneId(pendingRegenSceneId);
+  setPendingRegenSceneId(null);
+}, [pendingRegenSceneId, setCurrentSceneId]);
+
+/** User chose "Descartar" in regen confirm modal */
+const confirmRegenDiscard = useCallback(() => {
+  if (!pendingRegenSceneId) return;
+  handleRegenUndo();
+  setCurrentSceneId(pendingRegenSceneId);
+  setPendingRegenSceneId(null);
+}, [pendingRegenSceneId, handleRegenUndo, setCurrentSceneId]);
+```
+
+- [ ] **Step 7: Add `regenState` and `onRegenerateClick` props to `<SceneSidebar>` in the JSX (around line 936)**
+
+Find the `<SceneSidebar` JSX and add the new props:
+
+```tsx
+<SceneSidebar
+  collapsed={sidebarCollapsed}
+  onCollapseChange={setSidebarCollapsed}
+  onSceneSelect={gatedSceneSwitch}
+  onRetryOutline={onRetryOutline}
+  regenState={regenState === 'regenerating' ? 'regenerating' : regenState === 'review' ? 'review' : 'idle'}
+  onRegenerateClick={openRegenerateDialog}
+/>
+```
+
+- [ ] **Step 8: Add the review bar to the JSX, between the CanvasArea closing div and the Roundtable div (around line 993)**
+
+```tsx
+{/* Review bar — shown when a regenerated version is pending acceptance */}
+{regenState === 'review' && (
+  <div className="shrink-0 flex items-center justify-between gap-3 px-4 py-2 bg-green-50 dark:bg-green-950/30 border-t border-green-200 dark:border-green-800 text-sm">
+    <span className="text-green-700 dark:text-green-300 font-medium">
+      {t('stage.regen.reviewBar')}
+    </span>
+    <div className="flex gap-2">
+      <Button size="sm" variant="outline" onClick={handleRegenEditAgain}>
+        ✏ {t('stage.regen.editAgain')}
+      </Button>
+      <Button size="sm" variant="outline" className="text-red-600 border-red-300 hover:bg-red-50 dark:text-red-400 dark:border-red-700 dark:hover:bg-red-950/30" onClick={handleRegenUndo}>
+        ↩ {t('stage.regen.undo')}
+      </Button>
+      <Button size="sm" className="bg-green-600 hover:bg-green-700 text-white" onClick={handleRegenAccept}>
+        ✓ {t('stage.regen.accept')}
+      </Button>
+    </div>
+  </div>
+)}
+```
+
+- [ ] **Step 9: Add the `RegenerateSlideDialog` to the JSX (below the existing `AlertDialog`)**
+
+Find the closing `</AlertDialog>` (around line 1235) and add after it:
+
+```tsx
+{/* Regenerate Slide Dialog */}
+{currentScene?.type === 'slide' && (regenState === 'dialog_open' || regenState === 'regenerating') && (
+  (() => {
+    const outline = useStageStore.getState().outlines.find((o) => o.order === currentScene.order);
+    if (!outline) return null;
+    return (
+      <RegenerateSlideDialog
+        open={regenState === 'dialog_open'}
+        scene={currentScene}
+        outline={outline}
+        initialValues={lastRegenValues ?? undefined}
+        onRegenerate={handleRegenerate}
+        onClose={() => setRegenState('idle')}
+      />
+    );
+  })()
+)}
+
+{/* Regen confirm modal — shown when navigating away during review */}
+<AlertDialog open={!!pendingRegenSceneId}>
+  <AlertDialogContent className="max-w-md rounded-2xl">
+    <VisuallyHidden>
+      <AlertDialogTitle>{t('stage.regen.confirmTitle')}</AlertDialogTitle>
+    </VisuallyHidden>
+    <div className="px-6 pt-6">
+      <div className="flex items-start gap-3">
+        <AlertTriangle className="w-5 h-5 text-amber-500 shrink-0 mt-0.5" />
+        <div>
+          <p className="font-semibold text-gray-900 dark:text-gray-100 mb-1">
+            {t('stage.regen.confirmTitle')}
+          </p>
+          <p className="text-sm text-gray-600 dark:text-gray-400">
+            {t('stage.regen.confirmBody').replace('{title}', currentScene?.title ?? '')}
+          </p>
+        </div>
+      </div>
+    </div>
+    <AlertDialogFooter className="px-6 pb-5 pt-3 flex-row gap-3">
+      <AlertDialogCancel onClick={confirmRegenDiscard} className="flex-1 rounded-xl">
+        {t('stage.regen.confirmDiscard')}
+      </AlertDialogCancel>
+      <AlertDialogAction
+        onClick={confirmRegenKeep}
+        className="flex-1 rounded-xl bg-green-600 hover:bg-green-700"
+      >
+        {t('stage.regen.confirmKeep')}
+      </AlertDialogAction>
+    </AlertDialogFooter>
+  </AlertDialogContent>
+</AlertDialog>
+```
+
+**Important:** The `RegenerateSlideDialog` usage above uses an IIFE to call a hook (`useStageStore`) inside JSX, which is invalid. Instead, derive the outline at the component level. Replace the dialog block with:
+
+```tsx
+{/* Regenerate Slide Dialog */}
+{(() => {
+  if (!currentScene || currentScene.type !== 'slide') return null;
+  if (regenState !== 'dialog_open') return null;
+  const outline = outlines.find((o) => o.order === currentScene.order);
+  if (!outline) return null;
+  return (
+    <RegenerateSlideDialog
+      open={true}
+      scene={currentScene}
+      outline={outline}
+      initialValues={lastRegenValues ?? undefined}
+      onRegenerate={handleRegenerate}
+      onClose={() => setRegenState('idle')}
+    />
+  );
+})()}
+```
+
+And add `outlines` to the destructure from `useStageStore` at the top:
+
+```typescript
+const { mode, getCurrentScene, scenes, outlines, currentSceneId, setCurrentSceneId, generatingOutlines } =
+  useStageStore();
+```
+
+- [ ] **Step 10: Verify TypeScript compiles with no errors**
+
+```bash
+cd /home/ubuntu/dev/OpenMAIC && pnpm exec tsc --noEmit 2>&1 | grep -E "stage\.tsx|ERROR" | head -20
+```
+
+Expected: No errors.
+
+- [ ] **Step 11: Run all tests to ensure no regressions**
+
+```bash
+cd /home/ubuntu/dev/OpenMAIC && pnpm test --reporter=verbose
+```
+
+Expected: All existing tests pass plus the new tests.
+
+- [ ] **Step 12: Commit**
+
+```bash
+git add components/stage.tsx
+git commit -m "feat: add regenerate-slide state machine, review bar, and confirm modal to Stage"
+```
+
+---
+
+## Task 8: Manual verification (golden path)
+
+Before declaring the feature complete, verify against the spec's test cases. You cannot use automated tools for UI testing — document what you see.
+
+- [ ] **Start the dev server**
+
+```bash
+cd /home/ubuntu/dev/OpenMAIC && pnpm dev
+```
+
+- [ ] **Test case 1 — Happy path (no media)**
+
+1. Open any course with at least one slide scene
+2. Select a slide in the sidebar
+3. Verify the ↺ Regen. button appears below the thumbnail
+4. Click ↺ Regen. — dialog opens with indication + audio text pre-loaded
+5. Edit the indication, press ↺ Regenerar
+6. Verify: dialog closes, sidebar thumbnail shows spinner, canvas shows skeleton during generation
+7. Verify: new slide appears, review bar is visible (Accept / Undo / Edit again)
+8. Click ✓ Accept — bar disappears, regenState returns to idle
+9. Click ↺ Regen. again → can open dialog again
+
+- [ ] **Test case 2 — Undo**
+
+1. Regenerate a slide (follow test case 1 steps 1–7)
+2. Click ↩ Undo — original slide is restored, bar disappears
+
+- [ ] **Test case 3 — Tornar a editar**
+
+1. Regenerate a slide
+2. In review state, click ✏ Edit again
+3. Verify dialog reopens with the values you entered (not the original outline values)
+
+- [ ] **Test case 4 — Navigate away during review (Descartar)**
+
+1. Regenerate a slide, enter review state
+2. Click a different scene in the sidebar
+3. Verify: modal "Conservar la nova versió?" appears
+4. Click Descartar — original slide restored, new scene selected
+
+- [ ] **Test case 5 — Navigate away during review (Sí, conservar)**
+
+1. Regenerate a slide, enter review state
+2. Click a different scene in the sidebar
+3. Verify: modal appears
+4. Click Sí, conservar — new version kept, new scene selected
+
+- [ ] **Test case 6 — Auto-prompt generation**
+
+1. Open a slide that originally had no media
+2. Open regen dialog, select Imatge in the media radio group
+3. Verify: "✨ Generant prompt…" label appears
+4. Verify: prompt arrives and textarea becomes editable
+5. Verify: ↺ Regenerar button is disabled until prompt arrives
+
+- [ ] **Final commit after manual verification**
+
+```bash
+git add -A
+git commit -m "feat: regenerate-slide — complete feature implementation"
+```
diff --git a/docs/superpowers/specs/2026-04-12-regenerate-slide-blocks-design.md b/docs/superpowers/specs/2026-04-12-regenerate-slide-blocks-design.md
new file mode 100644
index 000000000..4bf0ee940
--- /dev/null
+++ b/docs/superpowers/specs/2026-04-12-regenerate-slide-blocks-design.md
@@ -0,0 +1,240 @@
+# Regenerate Slide — Block Toggles + Title Editing
+
+**Date:** 2026-04-12
+**Branch:** `feat/regenerate-slide`
+**Status:** Approved
+
+---
+
+## Context
+
+The regenerate-slide dialog (`components/classroom/regenerate-slide-dialog.tsx`) already supports toggling audio regeneration and choosing what to do with media. This spec adds:
+
+1. A **slide block toggle** (`regenerateSlide`) — mirrors the existing `modifyAudio` pattern. When OFF, content generation is skipped and the existing slide is preserved.
+2. An **editable title field** inside the slide block — `outline.title` drives the visual title on the generated slide and `scene.title` in the sidebar. Currently immutable in the dialog.
+3. A **conflict warning** when the user disables slide regeneration but requests new media on a slide that has no existing media slot.
+
+---
+
+## Scope
+
+- `RegenerateSlideDialog` (`components/classroom/regenerate-slide-dialog.tsx`)
+- `useSceneRegenerator` hook (`lib/hooks/use-scene-regenerator.ts`)
+- i18n files for all 5 locales (ca, en-US, zh-CN, ja-JP, ru-RU)
+- Unit tests (`tests/hooks/use-scene-regenerator.test.ts`)
+
+No changes to API routes or the Prisma schema.
+
+---
+
+## UI Structure
+
+```
+┌─────────────────────────────────────────────────────────┐
+│  ↺ Regenerar — [títol — actualitzat en temps real]     │
+├─────────────────────────────────────────────────────────┤
+│  SLIDE                       [Modificar slide ●──○]    │
+│    Títol   [_____________input________________________] │
+│    Indicació [___________textarea____________________] │
+│    Tema    [selector…]                                  │
+│  — (quan toggle OFF) —                                  │
+│    "La slide actual es conservarà."                     │
+│                                                         │
+│  ⚠ warning (si media nova + slide sense slot existent) │
+│                                                         │
+│  TEXT ÀUDIO                  [Modificar narració ●──○] │
+│    [textarea…]  [Generar amb IA]                        │
+│                                                         │
+│  MEDIA                                                  │
+│    [No regen.] [Cap] [Imatge] [Vídeo]                   │
+│    [textarea prompt si imatge/vídeo]                    │
+├─────────────────────────────────────────────────────────┤
+│  [Model] [Media]          [Cancel·lar] [↺ Regenerar]   │
+└─────────────────────────────────────────────────────────┘
+```
+
+### Slide block toggle
+
+- **Label:** `stage.regen.modifySlide` ("Modificar slide")
+- Default: `true` (toggle ON — regenerates slide, same behavior as today)
+- When **OFF**: hide indication textarea, title input, and theme selector; show `stage.regen.slideKeep` message
+- When **ON**: show title `<Input>`, indication `<Textarea>`, theme `<Select>` (as today, plus the new title input above)
+
+### Title input
+
+- First field inside the slide block, above the indication textarea
+- Label: `stage.regen.slideTitle` ("Títol")
+- `<Input>` (single line), pre-loaded with `outline.title`
+- The `<DialogTitle>` binds to the `title` state → updates live as the user types
+- Only editable when `regenerateSlide = true`. When `regenerateSlide = false`, `title` passes through unchanged and the header shows the original `scene.title`
+
+### Conflict warning
+
+Shown as an amber banner between the slide block and the audio block when **all three** conditions hold:
+
+1. `regenerateSlide === false`
+2. `mediaType === 'image' || mediaType === 'video'`
+3. `outlineToMediaType(outline) === 'none'` (slide has no existing media slot)
+
+Text: `stage.regen.slideWarningMediaNeeded`
+
+**Behavior on submit:** when the warning is active, `handleSubmit` sends `skipSlide: false` regardless of the toggle state. The slide is regenerated to create the media placeholder element. The warning informs the user of this automatic override.
+
+---
+
+## Type Changes
+
+### `RegenerateFormValues`
+
+```typescript
+export interface RegenerateFormValues {
+  title: string;             // NEW — outline.title, editable when regenerateSlide=true
+  indication: string;
+  regenerateSlide: boolean;  // NEW — toggle: skip content/actions generation when false
+  audioText: string;
+  modifyAudio: boolean;
+  mediaType: 'none' | 'image' | 'video' | 'keep';
+  mediaPrompt: string;
+  themeId: string;
+}
+```
+
+### `RegenerateParams`
+
+```typescript
+export interface RegenerateParams {
+  outline: SceneOutline;
+  audioTextOverride: string;
+  mediaType: 'none' | 'image' | 'video' | 'keep';
+  mediaPrompt?: string;
+  skipAudio?: boolean;
+  skipSlide?: boolean;       // NEW — when true, skip Steps 1a + 1b
+  themeId?: string;
+}
+```
+
+---
+
+## Hook Changes (`use-scene-regenerator`)
+
+### `skipSlide` logic
+
+When `params.skipSlide === true`:
+
+- Skip Step 1a (`POST /api/generate/scene-content-only`)
+- Skip Step 1b (`POST /api/generate/scene-actions`)
+- Use the **existing scene** from the store as `newContent` and `newActions` (pre-captured before any mutation)
+- Steps 2 (audio) and 3 (media) run as normal against the existing content/actions
+
+**Safety override:** if `skipSlide === true` but `mediaType !== 'none' && mediaType !== 'keep'` and the existing scene canvas has no image/video element — force Steps 1a + 1b anyway (same as `skipSlide = false`). This is a belt-and-suspenders guard; the dialog already prevents this via the warning + submit override.
+
+**Media injection when `skipSlide = true` + new media + existing slot:**
+In the normal flow, Step 1 generates the slide with a `gen_img_1`/`gen_vid_1` placeholder element; the `SlideRenderer` resolves it via `useMediaGenerationStore`. When the slide is NOT regenerated, the existing canvas element has its own `src` (old media URL). After Step 3 completes, the hook must:
+1. Read the new media URL from `useMediaGenerationStore.getState()` for `elementId` `gen_img_1`/`gen_vid_1`
+2. Find the first matching element type (image/video) in the existing scene canvas
+3. Directly patch its `src` to the new URL via `store.updateScene(sceneId, { content: patchedContent })`
+
+This avoids a `SlideRenderer` lookup mismatch between canvas elementId and the media store key.
+
+### `scene.title` update
+
+After Step 1b (or when using existing content in skip mode), include `title` in the `updateScene` call:
+
+```typescript
+store.getState().updateScene(sceneId, {
+  title: outline.title,   // propagates edited title to sidebar
+  content: newContent,
+  actions: newActions,
+});
+```
+
+When `skipSlide = true` and no title change is possible (title field is read-only when toggle OFF), this call is omitted for content/actions but the existing scene title is already correct.
+
+---
+
+## i18n — New Keys (5 locales)
+
+| Key | ca | en-US | zh-CN | ja-JP | ru-RU |
+|-----|-----|-------|-------|-------|-------|
+| `slideTitle` | "Títol" | "Title" | "标题" | "タイトル" | "Заголовок" |
+| `modifySlide` | "Modificar slide" | "Modify slide" | "修改幻灯片" | "スライドを変更" | "Изменить слайд" |
+| `slideKeep` | "La slide actual es conservarà." | "Existing slide will be preserved." | "现有幻灯片将被保留。" | "既存のスライドが保持されます。" | "Существующий слайд будет сохранён." |
+| `slideWarningMediaNeeded` | "Per afegir nova imatge/vídeo, la slide s'haurà de regenerar igualment." | "To add new image/video, the slide must also be regenerated." | "添加新图片/视频时，幻灯片也将被重新生成。" | "新しい画像/動画を追加するには、スライドも再生成する必要があります。" | "Для добавления нового изображения/видео слайд также будет регенерирован." |
+
+---
+
+## Initialisation Logic
+
+On dialog open (`useEffect` on `open`):
+
+```typescript
+// existing
+setIndication(outlineToIndication(outline.description, outline.keyPoints));
+setAudioText(sceneToAudioText(scene));
+setModifyAudio(false);
+// new
+setTitle(outline.title);
+setRegenerateSlide(true);   // always default ON
+```
+
+When `initialValues` is provided (re-opening via "Tornar a editar"):
+
+```typescript
+setTitle(initialValues.title);
+setRegenerateSlide(initialValues.regenerateSlide);
+```
+
+---
+
+## `handleSubmit` in Dialog
+
+```typescript
+const handleSubmit = () => {
+  const { description, keyPoints } = indicationToOutline(indication);
+  const updatedOutline: SceneOutline = {
+    ...outline,
+    title: regenerateSlide ? title : outline.title,  // only update title if slide is being regenerated
+    description,
+    keyPoints,
+  };
+
+  // Conflict: media requested but no existing slot and slide toggle is OFF
+  const hasExistingMedia = outlineToMediaType(outline) !== 'none';
+  const needsNewMedia = mediaType === 'image' || mediaType === 'video';
+  const forceSlideRegen = !regenerateSlide && needsNewMedia && !hasExistingMedia;
+
+  onRegenerate({
+    outline: updatedOutline,
+    audioTextOverride: modifyAudio ? audioText : '',
+    mediaType,
+    mediaPrompt: mediaType !== 'none' && mediaType !== 'keep' ? mediaPrompt : undefined,
+    skipAudio: !modifyAudio,
+    skipSlide: !regenerateSlide && !forceSlideRegen,
+    themeId: themeId || undefined,
+  });
+};
+```
+
+---
+
+## Unit Tests
+
+Add cases in `tests/hooks/use-scene-regenerator.test.ts`:
+
+1. `skipSlide: true` — Steps 1a and 1b are **not** called; existing scene content/actions used; audio step runs.
+2. `skipSlide: true` + `mediaType: 'image'` + existing media slot — Steps 1a/1b skipped, media step runs.
+3. `skipSlide: true` + `mediaType: 'image'` + **no** existing media slot — Steps 1a/1b run despite `skipSlide: true` (safety override).
+4. `skipSlide: false` — full pipeline unchanged (regression).
+5. Title update: `outline.title` change propagates to `store.updateScene` call.
+
+---
+
+## Verification
+
+1. **Toggle OFF, audio unchanged, media keep:** dialog submits, no content generation call made, existing slide preserved, review bar appears.
+2. **Toggle OFF, modify audio:** TTS regenerated for existing speech actions with new text; slide unchanged.
+3. **Toggle OFF + new media + existing slot:** media generated and injected into existing slide; no content/actions regeneration.
+4. **Toggle OFF + new media + no slot (warning shown):** warning amber banner visible; on submit, slide IS regenerated; media placeholder created and filled.
+5. **Toggle ON + title edited:** `<DialogTitle>` updates live; regenerated slide shows new title; sidebar shows new title.
+6. **"Tornar a editar":** `initialValues.title` and `initialValues.regenerateSlide` restored correctly.
+7. **Regression — full regen (toggle ON, default):** identical behavior to pre-feature.
diff --git a/lib/hooks/use-scene-regenerator.ts b/lib/hooks/use-scene-regenerator.ts
new file mode 100644
index 000000000..0263024b6
--- /dev/null
+++ b/lib/hooks/use-scene-regenerator.ts
@@ -0,0 +1,454 @@
+'use client';
+
+import { useRef, useState, useCallback } from 'react';
+import { useStageStore } from '@/lib/store/stage';
+import { useMediaGenerationStore } from '@/lib/store/media-generation';
+import { useSettingsStore } from '@/lib/store/settings';
+import { useUserPrefsStore } from '@/lib/store/user-prefs';
+import { getCurrentModelConfig } from '@/lib/utils/model-config';
+import { generateAndStoreMedia } from '@/lib/media/media-orchestrator';
+import { generateAndStoreTTS } from '@/lib/audio/generate-and-store-tts';
+import { splitLongSpeechActions } from '@/lib/audio/tts-utils';
+import { createLogger } from '@/lib/logger';
+import type { SceneOutline } from '@/lib/types/generation';
+import type { Action, SpeechAction } from '@/lib/types/action';
+import type { MediaGenerationRequest } from '@/lib/media/types';
+import type { SceneContent, SlideContent } from '@/lib/types/stage';
+
+const log = createLogger('SceneRegenerator');
+
+// ── Pure helpers (also used by RegenerateSlideDialog) ──
+
+export function outlineToIndication(description: string, keyPoints: string[]): string {
+  const bulletLines = keyPoints.map((k) => `• ${k}`).join('\n');
+  return keyPoints.length > 0 ? `${description}\n${bulletLines}` : description;
+}
+
+export function indicationToOutline(indication: string): {
+  description: string;
+  keyPoints: string[];
+} {
+  const lines = indication.split('\n');
+  const keyPoints: string[] = [];
+  const descLines: string[] = [];
+  for (const line of lines) {
+    if (line.startsWith('• ')) {
+      keyPoints.push(line.slice(2).trim());
+    } else {
+      descLines.push(line);
+    }
+  }
+  return { description: descLines.join('\n').trim(), keyPoints };
+}
+
+export function buildMediaGenerations(
+  mediaType: 'none' | 'image' | 'video',
+  mediaPrompt?: string,
+): MediaGenerationRequest[] {
+  if (mediaType === 'none') return [];
+  const elementId = mediaType === 'image' ? 'gen_img_1' : 'gen_vid_1';
+  return [{ elementId, type: mediaType, prompt: mediaPrompt ?? '' }];
+}
+
+export function applyAudioOverride(actions: Action[], audioOverride: string): Action[] {
+  const segments = audioOverride
+    .split('\n\n')
+    .map((s) => s.trim())
+    .filter(Boolean);
+  let segIdx = 0;
+  return actions.map((a) => {
+    if (a.type === 'speech' && segIdx < segments.length) {
+      return { ...a, text: segments[segIdx++] } as SpeechAction;
+    }
+    return a;
+  });
+}
+
+/**
+ * Resolves the effective `skipSlide` value.
+ * When new media is requested but the existing slide has no media slot,
+ * the slide must be regenerated even if skipSlide was requested.
+ */
+export function resolveSkipSlide(
+  skipSlide: boolean,
+  mediaType: 'none' | 'image' | 'video' | 'keep',
+  hasExistingMediaSlot: boolean,
+): boolean {
+  if (!skipSlide) return false;
+  if (mediaType === 'none' || mediaType === 'keep') return true;
+  // New media requested — only skip if there is already a media element to replace
+  return hasExistingMediaSlot;
+}
+
+// ── Types ──
+
+export interface RegenerateParams {
+  outline: SceneOutline;
+  audioTextOverride: string;
+  mediaType: 'none' | 'image' | 'video' | 'keep';
+  mediaPrompt?: string;
+  /** When true, skip TTS generation and preserve existing speech audio from the scene. */
+  skipAudio?: boolean;
+  /** When true, skip slide content + actions generation and preserve the existing slide. */
+  skipSlide?: boolean;
+  /** Theme to apply during content generation. Falls back to server-side stage default. */
+  themeId?: string;
+}
+
+export type RegenerateProgress = 'idle' | 'content' | 'audio' | 'media' | 'done' | 'error';
+
+export interface RegenerateResult {
+  success: boolean;
+  /** Human-readable error message from the failing step, if any */
+  error?: string;
+}
+
+export interface UseSceneRegeneratorReturn {
+  regenerate: (sceneId: string, params: RegenerateParams) => Promise<RegenerateResult>;
+  progress: RegenerateProgress;
+  errorStep?: 'content' | 'audio' | 'media';
+  cancel: () => void;
+}
+
+// ── Internal: build model headers for generation API calls ──
+
+function getApiHeaders(): HeadersInit {
+  const config = getCurrentModelConfig();
+  const settings = useSettingsStore.getState();
+
+  return {
+    'Content-Type': 'application/json',
+    'x-model': config.modelString || '',
+    'x-provider-type': config.providerType || '',
+    // Image generation provider
+    'x-image-provider': settings.imageProviderId || '',
+    'x-image-model': settings.imageModelId || '',
+    // Video generation provider
+    'x-video-provider': settings.videoProviderId || '',
+    'x-video-model': settings.videoModelId || '',
+    // Media generation toggles
+    'x-image-generation-enabled': String(
+      useUserPrefsStore.getState().imageGenerationEnabled ?? false,
+    ),
+    'x-video-generation-enabled': String(
+      useUserPrefsStore.getState().videoGenerationEnabled ?? false,
+    ),
+  };
+}
+
+// ── Hook ──
+
+export function useSceneRegenerator(): UseSceneRegeneratorReturn {
+  const abortRef = useRef<AbortController | null>(null);
+  const [progress, setProgress] = useState<RegenerateProgress>('idle');
+  const [errorStep, setErrorStep] = useState<'content' | 'audio' | 'media' | undefined>();
+
+  const regenerate = useCallback(
+    async (sceneId: string, params: RegenerateParams): Promise<RegenerateResult> => {
+      abortRef.current?.abort();
+      const ctrl = new AbortController();
+      abortRef.current = ctrl;
+      const signal = ctrl.signal;
+
+      setProgress('content');
+      setErrorStep(undefined);
+
+      const store = useStageStore;
+      const stageId = store.getState().stage?.id;
+      const allOutlines = store.getState().outlines;
+
+      if (!stageId) {
+        log.error('Cannot regenerate: no active stage');
+        setProgress('error');
+        setErrorStep('content');
+        return { success: false, error: 'No active stage found' };
+      }
+
+      // Pre-step: capture existing data from the current scene before any update
+      const existingSpeechActions: SpeechAction[] = [];
+      type MediaElementInfo = { type: 'image' | 'video'; src: string };
+      const existingMediaElements: MediaElementInfo[] = [];
+      let oldSceneContent: SceneContent | null = null;
+      let oldSceneActions: Action[] | null = null;
+
+      if (params.skipAudio || params.mediaType === 'keep' || params.skipSlide) {
+        const oldScene = store.getState().scenes.find((s) => s.id === sceneId);
+        if (oldScene) {
+          if (params.skipAudio) {
+            for (const action of oldScene.actions ?? []) {
+              if (action.type === 'speech') existingSpeechActions.push(action as SpeechAction);
+            }
+          }
+          if ((params.mediaType === 'keep' || params.skipSlide) && oldScene.type === 'slide') {
+            for (const el of (oldScene.content as SlideContent).canvas.elements) {
+              if ((el.type === 'image' || el.type === 'video') && el.src) {
+                existingMediaElements.push({ type: el.type, src: el.src });
+              }
+            }
+          }
+          if (params.skipSlide) {
+            oldSceneContent = oldScene.content;
+            oldSceneActions = [...(oldScene.actions ?? [])];
+          }
+        }
+      }
+
+      // Resolve effective skipSlide: if new media is requested but there's no existing slot,
+      // we must regenerate the slide to create a placeholder element.
+      const effectiveSkipSlide = resolveSkipSlide(
+        params.skipSlide ?? false,
+        params.mediaType,
+        existingMediaElements.length > 0,
+      );
+
+      // Resolve the effective media type for the outline:
+      // 'keep' → use the type of the first existing media element (or 'none' if none found)
+      const resolvedMediaType: 'none' | 'image' | 'video' =
+        params.mediaType === 'keep' ? (existingMediaElements[0]?.type ?? 'none') : params.mediaType;
+
+      // Pre-step: set outline.mediaGenerations based on user's media selection
+      const outline: SceneOutline = {
+        ...params.outline,
+        mediaGenerations: buildMediaGenerations(resolvedMediaType, params.mediaPrompt),
+      };
+
+      // ── Steps 1a + 1b: Generate slide content and actions (or use existing) ──
+      let contentData: unknown;
+      let newActions: Action[];
+      let newContent: SceneContent;
+
+      if (effectiveSkipSlide) {
+        // Use the existing scene — no content or actions regeneration
+        if (!oldSceneContent || !oldSceneActions) {
+          log.error('Cannot skipSlide: existing scene content not captured');
+          setProgress('error');
+          setErrorStep('content');
+          return { success: false, error: 'Existing scene not found' };
+        }
+        newContent = oldSceneContent;
+        newActions = oldSceneActions;
+      } else {
+        // ── Step 1a: Generate slide content ──
+        try {
+          const contentRes = await fetch('/api/generate/scene-content-only', {
+            method: 'POST',
+            headers: getApiHeaders(),
+            body: JSON.stringify({ outline, stageId, themeId: params.themeId }),
+            signal,
+          });
+          const json = await contentRes.json();
+          if (!contentRes.ok || !json.success) {
+            throw new Error(json.error || `HTTP ${contentRes.status}`);
+          }
+          contentData = json.data;
+        } catch (err) {
+          if (signal.aborted) return { success: false };
+          log.error('Step 1 (content) failed:', err);
+          setProgress('error');
+          setErrorStep('content');
+          return { success: false, error: err instanceof Error ? err.message : String(err) };
+        }
+
+        if (signal.aborted) return { success: false };
+
+        // ── Step 1b: Generate scene actions ──
+        try {
+          const actionsRes = await fetch('/api/generate/scene-actions', {
+            method: 'POST',
+            headers: getApiHeaders(),
+            body: JSON.stringify({
+              outline,
+              allOutlines,
+              content: contentData,
+              stageId,
+            }),
+            signal,
+          });
+          const json = await actionsRes.json();
+          if (!actionsRes.ok || !json.success || !json.scene) {
+            throw new Error(json.error || `HTTP ${actionsRes.status}`);
+          }
+          if (!json.scene.content) {
+            throw new Error('Missing scene content in actions response');
+          }
+          newActions = json.scene.actions ?? [];
+          newContent = json.scene.content;
+        } catch (err) {
+          if (signal.aborted) return { success: false };
+          log.error('Step 1 (actions) failed:', err);
+          setProgress('error');
+          setErrorStep('content');
+          return { success: false, error: err instanceof Error ? err.message : String(err) };
+        }
+
+        if (signal.aborted) return { success: false };
+
+        // When keeping existing media, inject old src values into new content elements
+        if (
+          params.mediaType === 'keep' &&
+          existingMediaElements.length > 0 &&
+          newContent.type === 'slide'
+        ) {
+          const slideContent = newContent as SlideContent;
+          const updatedElements = slideContent.canvas.elements.map((el) => {
+            if (el.type === 'image') {
+              const old = existingMediaElements.find((e) => e.type === 'image');
+              if (old) return { ...el, src: old.src };
+            } else if (el.type === 'video') {
+              const old = existingMediaElements.find((e) => e.type === 'video');
+              if (old) return { ...el, src: old.src };
+            }
+            return el;
+          });
+          newContent = {
+            ...slideContent,
+            canvas: { ...slideContent.canvas, elements: updatedElements },
+          };
+        }
+
+        // If new media will be generated, reset any stale gen_img_1/gen_vid_1 task now so the
+        // component shows a skeleton immediately instead of flashing the previous regen's image.
+        if (params.mediaType === 'image' || params.mediaType === 'video') {
+          const staleId = params.mediaType === 'image' ? 'gen_img_1' : 'gen_vid_1';
+          useMediaGenerationStore.getState().resetTask(staleId);
+        }
+
+        // Immediately show new slide content (without audio yet)
+        store
+          .getState()
+          .updateScene(sceneId, { title: outline.title, content: newContent, actions: newActions });
+      }
+
+      // ── Step 2: Audio ──
+      if (params.skipAudio) {
+        // Preserve existing audio — map old speech actions (text + audioId + audioUrl) onto
+        // the new actions by index, so the narration stays unchanged without re-running TTS.
+        let speechIdx = 0;
+        const preservedActions = newActions.map((action) => {
+          if (action.type === 'speech') {
+            const old = existingSpeechActions[speechIdx++];
+            if (old) {
+              return {
+                ...action,
+                text: old.text,
+                ...(old.audioId ? { audioId: old.audioId } : {}),
+                ...(old.audioUrl ? { audioUrl: old.audioUrl } : {}),
+              } as SpeechAction;
+            }
+          }
+          return action;
+        });
+        store.getState().updateScene(sceneId, { actions: preservedActions });
+      } else {
+        setProgress('audio');
+
+        // Apply user audio override text to speech actions
+        const overriddenActions = params.audioTextOverride
+          ? applyAudioOverride(newActions, params.audioTextOverride)
+          : newActions;
+
+        // Split long speech actions per provider limits
+        const ttsProviderId = useSettingsStore.getState().ttsProviderId;
+        const speechActions = splitLongSpeechActions(overriddenActions, ttsProviderId);
+
+        // Commit overridden text to store immediately (before TTS — so text is always saved even if TTS fails)
+        store.getState().updateScene(sceneId, { actions: [...speechActions] });
+
+        const { ttsEnabled } = useUserPrefsStore.getState();
+        if (ttsEnabled && ttsProviderId !== 'browser-native-tts') {
+          for (let i = 0; i < speechActions.length; i++) {
+            if (signal.aborted) return { success: false };
+            const action = speechActions[i];
+            if (action.type !== 'speech') continue;
+            // TypeScript doesn't narrow Action to SpeechAction via type guard in this context
+            const speechAction = action as SpeechAction;
+            if (!speechAction.text) continue;
+            const audioId = `tts_${speechAction.id}`;
+            let audioUrl: string | undefined;
+            try {
+              audioUrl =
+                (await generateAndStoreTTS(audioId, speechAction.text, signal)) ?? undefined;
+            } catch (err) {
+              if (signal.aborted) return { success: false };
+              log.warn('TTS failed for action', speechAction.id, ':', err);
+            }
+            speechActions[i] = {
+              ...speechAction,
+              audioId,
+              ...(audioUrl ? { audioUrl } : {}),
+            } as SpeechAction;
+            // Update scene progressively as each TTS clip is ready
+            store.getState().updateScene(sceneId, { actions: [...speechActions] });
+          }
+        }
+      }
+
+      // ── Step 3: Media ──
+      if (params.mediaType !== 'none' && params.mediaType !== 'keep') {
+        if (signal.aborted) return { success: false };
+        setProgress('media');
+        const elementId = params.mediaType === 'image' ? 'gen_img_1' : 'gen_vid_1';
+        const req: MediaGenerationRequest = {
+          elementId,
+          type: params.mediaType,
+          prompt: params.mediaPrompt ?? '',
+        };
+        // Reset any stale task so enqueueTasks creates a fresh pending entry.
+        // Required for skipSlide=false: if a previous regen already stored gen_img_1,
+        // enqueueTasks would skip it and the new slide would flash the old image.
+        useMediaGenerationStore.getState().resetTask(elementId);
+        useMediaGenerationStore.getState().enqueueTasks(stageId, [req]);
+        try {
+          await generateAndStoreMedia(req, stageId, signal);
+        } catch (err) {
+          if (signal.aborted) return { success: false };
+          log.warn('Media generation failed:', err);
+        }
+
+        // Patch the canvas element src to the real server URL.
+        // This fixes two issues:
+        // 1. skipSlide=true: existing element has a real src (not a placeholder) so SlideRenderer
+        //    never consults the media store — direct canvas patch is required.
+        // 2. skipSlide=false: leaving src='gen_img_1' permanently causes cross-slide contamination
+        //    because all regens share the same placeholder key.
+        if (!signal.aborted && newContent.type === 'slide') {
+          const newMediaUrl = useMediaGenerationStore.getState().tasks[elementId]?.objectUrl;
+          if (newMediaUrl) {
+            // Append cache-busting timestamp so the browser fetches the newly generated
+            // image/video instead of serving the previous cached response for the same URL.
+            const cacheBustedUrl = `${newMediaUrl}?t=${Date.now()}`;
+            const slideContent = newContent as SlideContent;
+            const mediaElType = params.mediaType as 'image' | 'video';
+            const patchedElements = slideContent.canvas.elements.map((el) =>
+              el.type === mediaElType ? { ...el, src: cacheBustedUrl } : el,
+            );
+            newContent = {
+              ...slideContent,
+              canvas: { ...slideContent.canvas, elements: patchedElements },
+            };
+            store.getState().updateScene(sceneId, { content: newContent });
+          }
+        }
+      }
+
+      if (signal.aborted) return { success: false };
+
+      // ── Step 4: Outline sync ──
+      const freshOutlines = store.getState().outlines;
+      const updatedOutlines = freshOutlines.map((o) => (o.order === outline.order ? outline : o));
+      store.getState().setOutlines(updatedOutlines);
+
+      setProgress('done');
+      return { success: true };
+    },
+    [],
+  );
+
+  const cancel = useCallback(() => {
+    abortRef.current?.abort();
+    setProgress('idle');
+    setErrorStep(undefined);
+  }, []);
+
+  return { regenerate, progress, errorStep, cancel };
+}
diff --git a/lib/i18n/locales/ca.json b/lib/i18n/locales/ca.json
new file mode 100644
index 000000000..febbfcf0c
--- /dev/null
+++ b/lib/i18n/locales/ca.json
@@ -0,0 +1,1190 @@
+{
+  "common": {
+    "you": "Tu",
+    "confirm": "Confirmar",
+    "cancel": "Cancel·lar",
+    "loading": "Carregant..."
+  },
+  "home": {
+    "slogan": "Aprenentatge Generatiu en Aula Interactiva Multi-Agent",
+    "greeting": "Hola, "
+  },
+  "toolbar": {
+    "languageHint": "El curs es generarà en aquesta llengua",
+    "pdfParser": "Analitzador",
+    "pdfUpload": "Pujar PDF",
+    "removePdf": "Eliminar fitxer",
+    "webSearchOn": "Activat",
+    "webSearchOff": "Clic per activar",
+    "webSearchDesc": "Cerca informació actualitzada a la web abans de la generació",
+    "webSearchProvider": "Motor de cerca",
+    "webSearchNoProvider": "Configura la clau API de cerca a la Configuració",
+    "selectProvider": "Selecciona proveïdor",
+    "configureProvider": "Configura model",
+    "configureProviderHint": "Configura almenys un proveïdor de model per generar cursos",
+    "enterClassroom": "Entrar a l'aula",
+    "advancedSettings": "Configuració avançada",
+    "ttsTitle": "Síntesi de veu",
+    "ttsHint": "Trieu una veu per al professor IA",
+    "ttsPreview": "Previsualitzar",
+    "ttsPreviewing": "Reproduint...",
+    "theme": "Tema",
+    "themeHint": "Selecciona el tema visual",
+    "selectTheme": "Tema",
+    "activeTheme": "actiu",
+    "loadingThemes": "Carregant...",
+    "loadThemeError": "No s'han pogut carregar els temes"
+  },
+  "export": {
+    "pptx": "Exportar PPTX",
+    "resourcePack": "Exportar paquet de recursos",
+    "resourcePackDesc": "PPTX + pàgines interactives",
+    "exporting": "Exportant...",
+    "exportSuccess": "Exportació correcta",
+    "exportFailed": "Error en l'exportació",
+    "scorm": "Exportar SCORM 1.2",
+    "scormDesc": "Paquet de curs estandarditzat per a LMS",
+    "scormDialogTitle": "Exportar SCORM 1.2",
+    "scormDialogDesc": "Trieu com gestionar el contingut de vídeo",
+    "scormIncludeVideos": "Incloure vídeos (paquet complet, pot ser gran)",
+    "scormReplacePoster": "Substituir vídeos per imatges de portada (descàrrega més petita)",
+    "scormExport": "Exportar"
+  },
+  "stage": {
+    "currentScene": "Escena actual",
+    "generating": "Generant...",
+    "paused": "En pausa",
+    "generationFailed": "Error en la generació",
+    "confirmSwitchTitle": "Canviar escena",
+    "confirmSwitchMessage": "Hi ha un tema en curs. Canviar d'escena finalitzarà el tema actual. Esteu segurs?",
+    "generatingNextPage": "L'escena s'està generant, espereu si us plau...",
+    "fullscreen": "Pantalla completa",
+    "exitFullscreen": "Sortir de pantalla completa",
+    "regen": {
+      "dialogTitle": "Regenerar",
+      "indication": "Indicació",
+      "indicationPlaceholder": "Descriu el que hauria de cobrir aquesta slide…",
+      "audioText": "Text àudio",
+      "audioTextPlaceholder": "Text de narració per a aquesta slide…",
+      "media": "Media",
+      "mediaNone": "Cap",
+      "mediaKeep": "No regenerar",
+      "mediaImage": "Imatge",
+      "mediaVideo": "Vídeo",
+      "generatingPrompt": "Generant prompt…",
+      "promptOriginal": "Prompt original recuperat. Pots modificar-lo.",
+      "promptAutoGenerated": "Prompt generat automàticament. Edita'l si cal.",
+      "mediaPromptPlaceholder": "Descriu la imatge o el vídeo…",
+      "theme": "Tema",
+      "cancel": "Cancel·lar",
+      "regenerate": "Regenerar",
+      "reviewBar": "Versió regenerada — pendent d'acceptar",
+      "accept": "Acceptar",
+      "undo": "Desfer",
+      "editAgain": "Tornar a editar",
+      "confirmTitle": "Conservar la nova versió?",
+      "confirmBody": "Slide \"{title}\" té una versió regenerada pendent d'acceptar. Si canvies de slide sense acceptar, la nova versió es descartarà.",
+      "confirmKeep": "Sí, conservar",
+      "confirmDiscard": "Descartar",
+      "buttonLabel": "↺ Regen.",
+      "inProgress": "Regenerant slide…",
+      "stepContent": "Generant contingut…",
+      "stepAudio": "Generant àudio…",
+      "stepMedia": "Generant media…",
+      "modifyAudio": "Modificar narració",
+      "modifySlide": "Modificar slide",
+      "slideTitle": "Títol",
+      "slideKeep": "La slide actual es conservarà.",
+      "slideWarningMediaNeeded": "Per afegir nova imatge/vídeo, la slide s'haurà de regenerar igualment.",
+      "audioKeep": "La narració actual es conservarà — no es generarà nou àudio.",
+      "generateNarration": "Generar amb IA",
+      "generatingNarration": "Generant narració…",
+      "aiGenerationError": "Error en generar.",
+      "aiModelHint": "Selecciona un model LLM als controls de la part inferior esquerra."
+    }
+  },
+  "whiteboard": {
+    "title": "Pissarra interactiva",
+    "open": "Obrir pissarra",
+    "clear": "Netejar pissarra",
+    "minimize": "Minimitzar pissarra",
+    "ready": "La pissarra està llesta",
+    "readyHint": "Els elements apareixeran aquí quan els afegeixi la IA",
+    "clearSuccess": "Pissarra netejada correctament",
+    "clearError": "Error en netejar la pissarra: ",
+    "resetView": "Restablir vista",
+    "restoreError": "Error en restaurar la pissarra: ",
+    "history": "Historial",
+    "restore": "Restaurar",
+    "noHistory": "Encara no hi ha historial",
+    "restored": "Pissarra restaurada",
+    "elementCount": "{{count}} elements"
+  },
+  "quiz": {
+    "title": "Qüestionari",
+    "subtitle": "Posa a prova els teus coneixements",
+    "questionsCount": "preguntes",
+    "totalPrefix": "",
+    "pointsSuffix": "pts",
+    "startQuiz": "Iniciar qüestionari",
+    "multipleChoiceHint": "(Resposta múltiple — seleccioneu totes les respostes correctes)",
+    "inputPlaceholder": "Escriviu la vostra resposta aquí...",
+    "charCount": "caràcters",
+    "yourAnswer": "La vostra resposta:",
+    "notAnswered": "Sense resposta",
+    "aiComment": "Comentari IA",
+    "singleChoice": "Única",
+    "multipleChoice": "Múltiple",
+    "shortAnswer": "Resposta curta",
+    "analysis": "Anàlisi: ",
+    "excellent": "Excel·lent!",
+    "keepGoing": "Continua!",
+    "needsReview": "Cal repassar",
+    "correct": "correcte",
+    "incorrect": "incorrecte",
+    "answering": "En curs",
+    "submitAnswers": "Enviar respostes",
+    "aiGrading": "La IA està corregint...",
+    "aiGradingWait": "Espereu, analitzant les vostres respostes",
+    "quizReport": "Informe del qüestionari",
+    "retry": "Reintentar"
+  },
+  "roundtable": {
+    "teacher": "PROFESSOR",
+    "you": "TU",
+    "inputPlaceholder": "Escriviu el vostre missatge...",
+    "listening": "Escoltant...",
+    "processing": "Processant...",
+    "noSpeechDetected": "No s'ha detectat veu, torneu-ho a intentar",
+    "discussionEnded": "Discussió finalitzada",
+    "qaEnded": "P&R finalitzat",
+    "thinking": "Pensant",
+    "yourTurn": "El vostre torn",
+    "stopDiscussion": "Aturar discussió",
+    "autoPlay": "Reproducció automàtica",
+    "autoPlayOff": "Aturar reproducció automàtica",
+    "speed": "Velocitat",
+    "voiceInput": "Entrada de veu",
+    "voiceInputDisabled": "Entrada de veu desactivada",
+    "textInput": "Entrada de text",
+    "stopRecording": "Aturar gravació",
+    "startRecording": "Iniciar gravació"
+  },
+  "pbl": {
+    "legacyFormat": "Aquesta escena PBL utilitza un format antic. Torneu a generar el curs.",
+    "emptyProject": "El projecte PBL encara no s'ha generat. Creeu-lo mitjançant la generació de cursos.",
+    "roleSelection": {
+      "title": "Trieu el vostre rol",
+      "description": "Seleccioneu un rol per col·laborar en el projecte"
+    },
+    "workspace": {
+      "restart": "Reiniciar",
+      "confirmRestart": "Restablir tot el progrés?",
+      "confirm": "Confirmar",
+      "cancel": "Cancel·lar"
+    },
+    "issueboard": {
+      "title": "Tauler de tasques",
+      "noIssues": "Encara no hi ha tasques",
+      "statusDone": "Fet",
+      "statusActive": "Actiu",
+      "statusPending": "Pendent"
+    },
+    "chat": {
+      "title": "Discussió del projecte",
+      "currentIssue": "Tasca actual",
+      "mentionHint": "Useu @question per preguntar, @judge per enviar a revisió",
+      "placeholder": "Escriviu un missatge...",
+      "send": "Enviar",
+      "welcomeMessage": "Hola! Soc el vostre Agent de Preguntes per a aquesta tasca: \"{{title}}\"\n\nPer guiar el vostre treball, he preparat algunes preguntes:\n\n{{questions}}\n\nNo dubteu a fer-me @question qualsevol moment si necessiteu ajuda!",
+      "issueCompleteMessage": "Tasca \"{{completed}}\" completada! Passant a la tasca següent: \"{{next}}\"",
+      "allCompleteMessage": "🎉 Totes les tasques completades! Bon treball en el projecte!"
+    },
+    "guide": {
+      "howItWorks": "Com funciona",
+      "help": "Ajuda",
+      "title": "Ajuda",
+      "step1": {
+        "title": "Pas 1: Trieu un rol",
+        "desc": "Després de generar el projecte, seleccioneu un rol de la llista (rols no de sistema marcats amb 🟢)"
+      },
+      "step2": {
+        "title": "Pas 2: Completeu les tasques",
+        "desc": "Cada tasca representa un objectiu d'aprenentatge:",
+        "s1": {
+          "title": "Veieu la tasca actual",
+          "desc": "Comproveu el títol, la descripció i el responsable de la tasca"
+        },
+        "s2": {
+          "title": "Obteniu orientació",
+          "example": "@question Per on haig de començar?\n@question Com implemento aquesta funcionalitat?",
+          "desc": "L'Agent de Preguntes proporciona preguntes orientadores i pistes (sense respostes directes)"
+        },
+        "s3": {
+          "title": "Envieu el vostre treball",
+          "example": "@judge Ja he acabat, comproveu les meves Notes",
+          "desc": "L'Agent Avaluador avalua el vostre treball i dona comentaris:",
+          "complete": "Passa automàticament a la tasca següent",
+          "revision": "Millora basant-te en els comentaris"
+        }
+      },
+      "step3": {
+        "title": "Pas 3: Completeu el projecte",
+        "desc": "Quan totes les tasques estiguin fetes, el sistema mostra \"🎉 Projecte completat!\""
+      }
+    }
+  },
+  "share": {
+    "notReady": "Disponible quan la generació estigui completa"
+  },
+  "chat": {
+    "lecture": "Lliçó",
+    "noConversations": "Cap conversa",
+    "startConversation": "Escriu un missatge per començar a xatejar",
+    "noMessages": "Encara no hi ha missatges",
+    "ended": "finalitzat",
+    "unknown": "Desconegut",
+    "stopDiscussion": "Aturar discussió",
+    "endQA": "Finalitzar P&R",
+    "tabs": {
+      "lecture": "Notes",
+      "chat": "Xat"
+    },
+    "lectureNotes": {
+      "empty": "Les notes apareixeran aquí després de la reproducció de la lliçó",
+      "emptyHint": "Premeu reproduir per iniciar la lliçó",
+      "pageLabel": "Pàgina {{n}}",
+      "currentPage": "Actual"
+    },
+    "badge": {
+      "qa": "P&R",
+      "discussion": "DISC",
+      "lecture": "LLIÇ"
+    }
+  },
+  "actions": {
+    "names": {
+      "spotlight": "Focus",
+      "laser": "Làser",
+      "wb_open": "Obrir pissarra",
+      "wb_draw_text": "Text a la pissarra",
+      "wb_draw_shape": "Forma a la pissarra",
+      "wb_draw_chart": "Gràfic a la pissarra",
+      "wb_draw_latex": "Fórmula a la pissarra",
+      "wb_draw_table": "Taula a la pissarra",
+      "wb_draw_line": "Línia a la pissarra",
+      "wb_clear": "Netejar pissarra",
+      "wb_delete": "Eliminar element",
+      "wb_close": "Tancar pissarra",
+      "discussion": "Discussió"
+    },
+    "status": {
+      "inputStreaming": "En espera",
+      "inputAvailable": "Executant",
+      "outputAvailable": "Completat",
+      "outputError": "Error",
+      "outputDenied": "Denegat",
+      "running": "Executant",
+      "result": "Completat",
+      "error": "Error"
+    }
+  },
+  "agentBar": {
+    "readyToLearn": "Preparats per aprendre junts?",
+    "expandedTitle": "Configuració de rols de l'aula",
+    "configTooltip": "Clic per configurar els rols de l'aula",
+    "voiceLabel": "Veu",
+    "voiceLoading": "Carregant...",
+    "voiceAutoAssign": "Les veus s'assignaran automàticament"
+  },
+  "proactiveCard": {
+    "discussion": "Discussió",
+    "join": "Unir-se",
+    "skip": "Ometre",
+    "pause": "Pausar",
+    "resume": "Reprendre"
+  },
+  "voice": {
+    "startListening": "Entrada de veu",
+    "stopListening": "Aturar gravació"
+  },
+  "admin": {
+    "panel": "Panell d'administració",
+    "welcome": "Benvingut/da, {{name}}",
+    "stats": {
+      "registeredUsers": "Usuaris registrats",
+      "actionsToday": "Accions avui",
+      "actionsLast24h": "Accions (últimes 24h)"
+    },
+    "nav": {
+      "users": "Usuaris",
+      "config": "Configuració",
+      "courses": "Cursos generats",
+      "audit": "Auditoria"
+    },
+    "cards": {
+      "usersDesc": "Gestiona usuaris i invitacions",
+      "configDesc": "Models permesos i paràmetres globals",
+      "coursesDesc": "Tots els cursos del sistema",
+      "auditDesc": "Log complet d'accions"
+    },
+    "recentActivity": "Activitat recent",
+    "table": {
+      "action": "Acció",
+      "user": "Usuari",
+      "entity": "Entitat",
+      "date": "Data",
+      "system": "Sistema",
+      "noActivity": "Sense activitat registrada"
+    },
+    "backToApp": "Tornar a l'aplicació",
+    "logout": "Sortir",
+    "users": {
+      "title": "Gestió d'usuaris",
+      "invite": {
+        "title": "Convidar nou usuari",
+        "firstName": "Nom",
+        "lastName": "Cognom",
+        "email": "Correu electrònic",
+        "sending": "Enviant...",
+        "submit": "Convidar",
+        "errorCreating": "Error creant la invitació.",
+        "errorConnection": "Error de connexió.",
+        "emailSent": "✓ Invitació enviada per email.",
+        "emailNotSent": "⚠ Email no enviat (ACS no configurat). URL de la invitació:"
+      },
+      "table": {
+        "user": "Usuari",
+        "email": "Email",
+        "role": "Rol",
+        "status": "Estat",
+        "created": "Creat",
+        "loading": "Carregant...",
+        "noUsers": "Sense usuaris"
+      },
+      "status": {
+        "active": "Actiu",
+        "pending": "Pendent",
+        "inactive": "Inhabilitat"
+      },
+      "actions": {
+        "edit": "Editar",
+        "enable": "Habilitar",
+        "disable": "Inhabilitar",
+        "delete": "Esborra"
+      },
+      "confirmDelete": "Segur que vols esborrar aquest usuari? Aquesta acció no es pot desfer.",
+      "edit": {
+        "title": "Editar usuari",
+        "emailNote": "L'email no es pot modificar.",
+        "firstName": "Nom",
+        "lastName": "Cognom",
+        "org": "Organització",
+        "dept": "Departament",
+        "job": "Càrrec",
+        "city": "Ciutat",
+        "optional": "Opcional",
+        "saving": "Desant...",
+        "save": "Desar canvis",
+        "cancel": "Cancel·lar",
+        "errorSaving": "Error desant els canvis."
+      }
+    },
+    "config": {
+      "title": "Configuració global",
+      "allowedModels": {
+        "title": "Models permesos",
+        "desc": "Especifica quins models LLM poden usar els usuaris. Deixa buit per permetre tots.",
+        "placeholder": "Buit = tots els models permesos"
+      },
+      "loading": "Carregant...",
+      "saving": "Desant...",
+      "save": "Guardar",
+      "saved": "✓ Configuració guardada.",
+      "errorSaving": "Error desant.",
+      "errorConnection": "Error de connexió."
+    },
+    "courses": {
+      "title": "Cursos generats",
+      "subtitle": "Tots els cursos del sistema amb el seu propietari.",
+      "loading": "Carregant…",
+      "empty": "Encara no hi ha cap curs generat.",
+      "table": {
+        "name": "Nom",
+        "scenes": "Escenes",
+        "owner": "Propietari",
+        "createdAt": "Data creació",
+        "noTitle": "Sense títol",
+        "unknownOwner": "Desconegut"
+      },
+      "delete": {
+        "title": "Eliminar curs",
+        "confirm": "Aquesta acció és irreversible. S'eliminarà el curs i tot el seu contingut.",
+        "cancel": "Cancel·lar",
+        "button": "Eliminar",
+        "tooltip": "Eliminar curs"
+      }
+    },
+    "audit": {
+      "title": "Log d'auditoria",
+      "filter": {
+        "action": "Acció",
+        "from": "Des de",
+        "to": "Fins a",
+        "apply": "Filtrar",
+        "clear": "Netejar"
+      },
+      "records": "{{count}} registres",
+      "table": {
+        "action": "Acció",
+        "user": "Usuari",
+        "entity": "Entitat",
+        "ip": "IP",
+        "date": "Data",
+        "system": "Sistema",
+        "noRecords": "Sense registres",
+        "loading": "Carregant..."
+      },
+      "pagination": {
+        "prev": "← Anterior",
+        "next": "Següent →",
+        "page": "Pàgina {{page}}"
+      }
+    }
+  },
+  "classroom": {
+    "recentClassrooms": "Recent",
+    "today": "Avui",
+    "yesterday": "Ahir",
+    "daysAgo": "dies enrere",
+    "slides": "diapositives",
+    "nameCopied": "Nom copiat",
+    "deleteConfirmTitle": "Eliminar",
+    "delete": "Eliminar",
+    "rename": "Reanomenar",
+    "renamePlaceholder": "Introduïu el nom de l'aula",
+    "renameFailed": "Error en reanomenar l'aula",
+    "regenerateAudio": "Regenerar àudio",
+    "regenerateAudioSuccess": "S'han regenerat {{count}} clips d'àudio",
+    "regenerateAudioFailed": "Error en regenerar l'àudio",
+    "regenerateAudioNoSpeech": "Aquesta aula no té àudio de veu per regenerar",
+    "regenerateAudioSetupNeeded": "Configureu primer un proveïdor TTS disponible",
+    "regenerateAudioBrowserNativeUnsupported": "El TTS natiu del navegador no admet la regeneració massiva d'àudio de l'aula"
+  },
+  "upload": {
+    "pdfSizeLimit": "Suporta fitxers PDF de fins a 50MB",
+    "generateFailed": "Error en generar l'aula, torneu-ho a intentar",
+    "requirementPlaceholder": "Digueu-me qualsevol cosa que vulgueu aprendre, per exemple:\n\"Ensenyeu-me Python des de zero en 30 minuts\"\n\"Expliqueu la Transformada de Fourier a la pissarra\"\n\"Com es juga al joc de taula Avalon\"",
+    "requirementRequired": "Introduïu els requisits del curs",
+    "fileTooLarge": "Fitxer massa gran. Seleccioneu un PDF inferior a 50MB"
+  },
+  "generation": {
+    "analyzingPdf": "Analitzant document PDF",
+    "analyzingPdfDesc": "Extraient l'estructura i contingut del document...",
+    "pdfLoadFailed": "Error en carregar el fitxer PDF, torneu-ho a intentar",
+    "pdfParseFailed": "Error en analitzar el PDF",
+    "streamNotReadable": "No es pot llegir el flux de generació",
+    "generatingOutlines": "Elaborant esquema del curs",
+    "generatingOutlinesDesc": "Estructurant el camí d'aprenentatge...",
+    "generatingSlideContent": "Generant contingut de les pàgines",
+    "generatingSlideContentDesc": "Creant diapositives, qüestionaris i contingut interactiu...",
+    "generatingActions": "Generant accions didàctiques",
+    "generatingActionsDesc": "Organitzant narracions, focus i interaccions...",
+    "generationComplete": "Generació completada!",
+    "generationFailed": "Error en la generació",
+    "generatingCourse": "Generant el curs",
+    "openingClassroom": "Obrint l'aula...",
+    "outlineReady": "Esquema del curs generat",
+    "generatingFirstPage": "Generant la primera pàgina...",
+    "firstPageReady": "Primera pàgina llesta! Obrint l'aula...",
+    "speechFailed": "Error en la generació de veu",
+    "retryScene": "Reintentar",
+    "retryingScene": "Regenerant...",
+    "backToHome": "Tornar a l'inici",
+    "sessionNotFound": "Sessió no trobada",
+    "sessionNotFoundDesc": "Ompliu els requisits del curs per iniciar el procés de generació.",
+    "goBackAndRetry": "Tornar enrere i reintentar",
+    "classroomReady": "El vostre entorn d'aprenentatge IA personalitzat s'ha generat correctament.",
+    "aiWorking": "Agents IA treballant...",
+    "textTruncated": "El text del document és llarg, s'utilitzen els primers {{n}} caràcters per a la generació",
+    "imageTruncated": "S'han trobat {{total}} imatges, que superen el límit de {{max}}. Les imatges addicionals només usaran descripcions de text",
+    "agentGeneration": "Generant rols de l'aula",
+    "agentGenerationDesc": "Generant rols basats en el contingut del curs...",
+    "agentRevealTitle": "Els vostres rols de l'aula",
+    "viewAgents": "Veure rols",
+    "continue": "Continuar",
+    "outlineRetrying": "Problema en la generació de l'esquema, reintentant...",
+    "outlineEmptyResponse": "El model no ha retornat cap esquema vàlid. Comproveu la configuració del model i torneu-ho a intentar",
+    "outlineGenerateFailed": "Error en generar l'esquema, torneu-ho a intentar més tard",
+    "webSearching": "Cerca web",
+    "webSearchingDesc": "Cercant a la web informació actualitzada",
+    "webSearchFailed": "Error en la cerca web"
+  },
+  "settings": {
+    "title": "Configuració",
+    "description": "Configura els paràmetres de l'aplicació",
+    "language": "Idioma",
+    "languageDesc": "Seleccioneu l'idioma de la interfície",
+    "theme": "Tema",
+    "themeDesc": "Seleccioneu el mode de tema (Clar/Fosc/Sistema)",
+    "themeOptions": {
+      "light": "Clar",
+      "dark": "Fosc",
+      "system": "Sistema"
+    },
+    "apiKey": "Clau API",
+    "apiKeyDesc": "Configureu la vostra clau API",
+    "apiBaseUrl": "URL de l'endpoint API",
+    "apiBaseUrlDesc": "Configureu la URL de l'endpoint API",
+    "apiKeyRequired": "La clau API no pot estar buida",
+    "apiKeyStored": "Clau API emmagatzemada",
+    "model": "Configuració del model",
+    "modelDesc": "Configureu models IA",
+    "modelPlaceholder": "Introduïu o seleccioneu el nom del model",
+    "ttsModel": "Model TTS",
+    "ttsModelDesc": "Configureu models TTS",
+    "ttsModelPlaceholder": "Introduïu o seleccioneu el nom del model TTS",
+    "ttsModelOptions": {
+      "openaiTts": "OpenAI TTS",
+      "azureTts": "Azure TTS"
+    },
+    "availableModels": "Models disponibles",
+    "modelSelectedViaVoice": "El model es determina per la selecció de veu",
+    "testConnection": "Provar connexió",
+    "testConnectionDesc": "Proveu si la configuració API actual és disponible",
+    "testing": "Provant...",
+    "agentSettings": "Configuració d'agents",
+    "agentSettingsDesc": "Seleccioneu els agents per participar a la conversa. Seleccioneu 1 per al mode d'agent únic, seleccioneu múltiples per al mode col·laboratiu multi-agent.",
+    "agentMode": "Mode d'agent",
+    "agentModePreset": "Preestablert",
+    "agentModeAuto": "Generació automàtica",
+    "agentModeAutoDesc": "La IA generarà automàticament rols adequats",
+    "autoAgentCount": "Nombre d'agents",
+    "autoAgentCountDesc": "Nombre d'agents a generar automàticament (inclou el professor)",
+    "atLeastOneAgent": "Seleccioneu almenys 1 agent",
+    "singleAgentMode": "Mode d'agent únic",
+    "directAnswer": "Resposta directa",
+    "multiAgentMode": "Mode multi-agent",
+    "agentsCollaborating": "Discussió col·laborativa",
+    "agentsCollaboratingCount": "{{count}} agents seleccionats per a la discussió col·laborativa",
+    "maxTurns": "Torns màxims de discussió",
+    "maxTurnsDesc": "El nombre màxim de torns de discussió entre agents (cada agent completa accions i respon compta com un torn)",
+    "priority": "Prioritat",
+    "actions": "Accions",
+    "actionCount": "{{count}} accions",
+    "selectedAgent": "Agent seleccionat",
+    "selectedAgents": "Agents seleccionats",
+    "required": "Obligatori",
+    "agentNames": {
+      "default-1": "Professor IA",
+      "default-2": "Assistent IA",
+      "default-3": "Animador de classe",
+      "default-4": "Ment curiosa",
+      "default-5": "Apuntador",
+      "default-6": "Pensador profund"
+    },
+    "agentRoles": {
+      "teacher": "Professor",
+      "assistant": "Assistent",
+      "student": "Estudiant"
+    },
+    "agentDescriptions": {
+      "default-1": "Professor principal amb explicacions clares i estructurades",
+      "default-2": "Dona suport a l'aprenentatge i ajuda a aclarir els punts clau",
+      "default-3": "Aporta humor i energia a l'aula",
+      "default-4": "Sempre curiós, li encanta preguntar el per què i el com",
+      "default-5": "Registra i organitza diligentment les notes de classe",
+      "default-6": "Pensa profundament i explora l'essència dels temes"
+    },
+    "close": "Tancar",
+    "save": "Desar",
+    "providers": "LLM",
+    "addProviderDescription": "Afegiu proveïdors de models personalitzats per ampliar els models IA disponibles",
+    "providerNames": {
+      "openai": "OpenAI",
+      "anthropic": "Claude",
+      "google": "Gemini",
+      "deepseek": "DeepSeek",
+      "qwen": "Qwen",
+      "kimi": "Kimi",
+      "minimax": "MiniMax",
+      "glm": "GLM",
+      "siliconflow": "SiliconFlow"
+    },
+    "providerTypes": {
+      "openai": "Protocol OpenAI",
+      "anthropic": "Protocol Claude",
+      "google": "Protocol Gemini"
+    },
+    "modelCount": "models",
+    "modelSingular": "model",
+    "defaultModel": "Model per defecte",
+    "webSearch": "Cerca web",
+    "mcp": "MCP",
+    "knowledgeBase": "Base de coneixement",
+    "documentParser": "Analitzador de documents",
+    "conversationSettings": "Conversa",
+    "keyboardShortcuts": "Dreceres",
+    "generalSettings": "General",
+    "systemSettings": "Sistema",
+    "addProvider": "Afegir",
+    "importFromClipboard": "Importar del porta-retalls",
+    "apiSecret": "Clau API",
+    "apiHost": "Base URL",
+    "requestUrl": "URL de sol·licitud",
+    "models": "Models",
+    "addModel": "Nou",
+    "reset": "Restablir",
+    "fetch": "Obtenir",
+    "connectionSuccess": "Connexió correcta",
+    "connectionFailed": "Error de connexió",
+    "capabilities": {
+      "vision": "Visió",
+      "tools": "Eines",
+      "streaming": "Streaming"
+    },
+    "contextWindow": "Context",
+    "contextShort": "ctx",
+    "outputWindow": "Sortida",
+    "addProviderButton": "Afegir",
+    "addProviderDialog": "Afegir proveïdor de model",
+    "providerName": "Nom",
+    "providerNamePlaceholder": "p. ex., El meu proxy OpenAI",
+    "providerNameRequired": "Introduïu el nom del proveïdor",
+    "providerApiMode": "Mode API",
+    "apiModeOpenAI": "Protocol OpenAI",
+    "apiModeAnthropic": "Protocol Claude",
+    "apiModeGoogle": "Protocol Gemini",
+    "defaultBaseUrl": "Base URL per defecte",
+    "providerIcon": "URL de la icona del proveïdor",
+    "requiresApiKey": "Requereix clau API",
+    "deleteProvider": "Eliminar proveïdor",
+    "deleteProviderConfirm": "Esteu segurs que voleu eliminar aquest proveïdor?",
+    "cannotDeleteBuiltIn": "No es pot eliminar el proveïdor integrat",
+    "resetToDefault": "Restablir valors per defecte",
+    "resetToDefaultDescription": "Restaura la llista de models a la configuració per defecte (la clau API i la Base URL es conservaran)",
+    "resetConfirmDescription": "Això eliminarà tots els models personalitzats i restaurarà la llista de models per defecte integrada. La clau API i la Base URL es conservaran.",
+    "confirmReset": "Confirmar restabliment",
+    "resetSuccess": "S'ha restablit correctament a la configuració per defecte",
+    "saveSuccess": "Configuració desada",
+    "saveFailed": "Error en desar la configuració, torneu-ho a intentar",
+    "cannotDeleteBuiltInModel": "No es pot eliminar el model integrat",
+    "cannotEditBuiltInModel": "No es pot editar el model integrat",
+    "modelIdRequired": "Introduïu l'ID del model",
+    "noModelsAvailable": "No hi ha models disponibles per a les proves",
+    "providerMetadata": "Metadades del proveïdor",
+    "editModel": "Editar model",
+    "editModelDescription": "Editeu la configuració i les capacitats del model",
+    "addNewModel": "Nou model",
+    "addNewModelDescription": "Afegiu una nova configuració de model",
+    "modelId": "ID del model",
+    "modelIdPlaceholder": "p. ex., gpt-4o",
+    "modelName": "Nom de visualització",
+    "modelNamePlaceholder": "Opcional",
+    "modelCapabilities": "Capacitats",
+    "advancedSettings": "Configuració avançada",
+    "contextWindowLabel": "Finestra de context",
+    "contextWindowPlaceholder": "p. ex., 128000",
+    "outputWindowLabel": "Tokens de sortida màxims",
+    "outputWindowPlaceholder": "p. ex., 4096",
+    "testModel": "Provar model",
+    "deleteModel": "Eliminar",
+    "cancelEdit": "Cancel·lar",
+    "saveModel": "Desar",
+    "modelsManagementDescription": "Gestioneu els models per a aquest proveïdor. Per seleccionar el model actiu, aneu a \"General\".",
+    "howToUse": "Com utilitzar",
+    "step1ConfigureProvider": "Aneu a \"Proveïdors de model\", seleccioneu o afegiu un proveïdor i configureu els paràmetres de connexió (clau API, Base URL, etc.)",
+    "step2SelectModel": "Seleccioneu el model que voleu usar a \"Model actiu\" a continuació",
+    "step3StartUsing": "Després de desar, el sistema usarà el model seleccionat",
+    "activeModel": "Model actiu",
+    "activeModelDescription": "Seleccioneu el model per a les converses IA i la generació de contingut",
+    "selectModel": "Seleccionar model",
+    "searchModels": "Cercar models",
+    "noModelsFound": "No s'han trobat models coincidents",
+    "noConfiguredProviders": "No hi ha proveïdors configurats",
+    "configureProvidersFirst": "Configureu els paràmetres de connexió del proveïdor a \"Proveïdors de model\" a l'esquerra",
+    "currentlyUsing": "Usant actualment",
+    "ttsSettings": "Síntesi de veu",
+    "asrSettings": "Reconeixement de veu",
+    "audioSettings": "Configuració d'àudio",
+    "ttsSection": "Text a veu (TTS)",
+    "asrSection": "Reconeixement automàtic de veu (ASR)",
+    "ttsDescription": "TTS (Text a veu) - Converteix text en veu",
+    "asrDescription": "ASR (Reconeixement automàtic de veu) - Converteix veu en text",
+    "enableTTS": "Activar síntesi de veu",
+    "ttsEnabledDescription": "Quan s'activa, es generarà àudio de veu durant la creació del curs",
+    "ttsVoiceConfigHint": "La veu per agent es pot configurar a \"Configuració de rols de l'aula\" a la pàgina d'inici",
+    "enableASR": "Activar reconeixement de veu",
+    "asrEnabledDescription": "Quan s'activa, els estudiants poden usar el micròfon per a l'entrada de veu",
+    "ttsProvider": "Proveïdor TTS",
+    "ttsLanguageFilter": "Filtre d'idioma",
+    "allLanguages": "Tots els idiomes",
+    "ttsVoice": "Veu",
+    "ttsSpeed": "Velocitat",
+    "ttsBaseUrl": "Base URL",
+    "ttsApiKey": "Clau API",
+    "doubaoAppId": "App ID",
+    "doubaoAccessKey": "Clau d'accés",
+    "asrProvider": "Proveïdor ASR",
+    "asrLanguage": "Idioma de reconeixement",
+    "asrBaseUrl": "Base URL",
+    "asrApiKey": "Clau API",
+    "enterApiKey": "Introduïu la clau API",
+    "enterCustomBaseUrl": "Introduïu la Base URL personalitzada",
+    "browserNativeNote": "L'ASR natiu del navegador no requereix configuració i és completament gratuït",
+    "providerOpenAITTS": "OpenAI TTS (gpt-4o-mini-tts)",
+    "providerAzureTTS": "Azure TTS",
+    "providerAzureFoundryTTS": "Azure AI Foundry TTS",
+    "providerGLMTTS": "GLM TTS",
+    "providerQwenTTS": "Qwen TTS (Alibaba Cloud Bailian)",
+    "providerDoubaoTTS": "Doubao TTS 2.0 (Volcengine)",
+    "providerElevenLabsTTS": "ElevenLabs TTS",
+    "providerMiniMaxTTS": "MiniMax TTS",
+    "providerBrowserNativeTTS": "TTS natiu del navegador",
+    "providerOpenAIWhisper": "OpenAI ASR (gpt-4o-mini-transcribe)",
+    "providerBrowserNative": "ASR natiu del navegador",
+    "providerQwenASR": "Qwen ASR (Alibaba Cloud Bailian)",
+    "providerUnpdf": "unpdf (Integrat)",
+    "providerMinerU": "MinerU",
+    "browserNativeTTSNote": "El TTS natiu del navegador no requereix configuració i és completament gratuït, usant les veus integrades del sistema",
+    "testTTS": "Provar TTS",
+    "testASR": "Provar ASR",
+    "testSuccess": "Prova correcta",
+    "testFailed": "Prova fallida",
+    "ttsTestText": "Text de prova TTS",
+    "ttsTestSuccess": "Prova TTS correcta, àudio reproduït",
+    "ttsTestFailed": "Prova TTS fallida",
+    "asrTestSuccess": "Reconeixement de veu correcte",
+    "asrTestFailed": "Reconeixement de veu fallat",
+    "asrResult": "Resultat del reconeixement",
+    "asrNotSupported": "El navegador no suporta l'API de reconeixement de veu",
+    "browserTTSNotSupported": "El navegador no suporta l'API de síntesi de veu",
+    "browserTTSNoVoices": "El navegador actual no té veus TTS disponibles",
+    "microphoneAccessDenied": "Accés al micròfon denegat",
+    "microphoneAccessFailed": "Error en accedir al micròfon",
+    "asrResultPlaceholder": "El resultat del reconeixement es mostrarà després de la gravació",
+    "useThisProvider": "Usar aquest proveïdor",
+    "fetchVoices": "Obtenir llista de veus",
+    "fetchingVoices": "Obtenint...",
+    "voicesFetched": "Veus obtingudes",
+    "fetchVoicesFailed": "Error en obtenir les veus",
+    "voiceApiKeyRequired": "Es requereix clau API",
+    "voiceBaseUrlRequired": "Es requereix Base URL",
+    "ttsTestTextPlaceholder": "Introduïu el text a convertir",
+    "ttsTestTextDefault": "Hola, aquesta és una prova de veu.",
+    "startRecording": "Iniciar gravació",
+    "stopRecording": "Aturar gravació",
+    "recording": "Gravant...",
+    "transcribing": "Transcrivint...",
+    "transcriptionResult": "Resultat de la transcripció",
+    "noTranscriptionResult": "Cap resultat de transcripció",
+    "baseUrlOptional": "Base URL (Opcional)",
+    "defaultValue": "Per defecte",
+    "voiceMarin": "Recomanat - Millor qualitat",
+    "voiceCedar": "Recomanat - Millor qualitat",
+    "voiceAlloy": "Neutre, equilibrat",
+    "voiceAsh": "Ferm, professional",
+    "voiceBallad": "Elegant, líric",
+    "voiceCoral": "Càlid, amigable",
+    "voiceEcho": "Masculí, clar",
+    "voiceFable": "Narratiu, vívid",
+    "voiceNova": "Femení, brillant",
+    "voiceOnyx": "Masculí, profund",
+    "voiceSage": "Savi, compost",
+    "voiceShimmer": "Femení, suau",
+    "voiceVerse": "Natural, fluid",
+    "glmVoiceTongtong": "Veu per defecte",
+    "glmVoiceChuichui": "Veu Chuichui",
+    "glmVoiceXiaochen": "Veu Xiaochen",
+    "glmVoiceJam": "Veu Jam",
+    "glmVoiceKazi": "Veu Kazi",
+    "glmVoiceDouji": "Veu Douji",
+    "glmVoiceLuodo": "Veu Luodo",
+    "qwenVoiceCherry": "Alegre, càlid i natural",
+    "qwenVoiceSerena": "Suau i dolç",
+    "qwenVoiceEthan": "Enèrgic i vibrant",
+    "qwenVoiceChelsie": "Noia virtual anime",
+    "qwenVoiceMomo": "Juganera i alegre",
+    "qwenVoiceVivian": "Maca i atrevida",
+    "qwenVoiceMoon": "Fresc i elegant",
+    "qwenVoiceMaia": "Intel·lectual i suau",
+    "qwenVoiceKai": "Un SPA per a les vostres orelles",
+    "qwenVoiceNofish": "Dissenyadora que no pronuncia sons retroflex",
+    "qwenVoiceBella": "Noia que no s'emborratxa",
+    "qwenVoiceJennifer": "Veu femenina americana de qualitat cinematogràfica",
+    "qwenVoiceRyan": "Ritme ràpid, actuació dramàtica",
+    "qwenVoiceKaterina": "Dona madura amb ritme memorable",
+    "qwenVoiceAiden": "Noi americà expert en cuina",
+    "qwenVoiceEldricSage": "Ancià estable i savi",
+    "qwenVoiceMia": "Suau com l'aigua de primavera",
+    "qwenVoiceMochi": "Nen adult intel·ligent amb innocència infantil",
+    "qwenVoiceBellona": "Veu potent, pronunciació clara",
+    "qwenVoiceVincent": "Veu ronca única explicant històries",
+    "qwenVoiceBunny": "Noia super maca",
+    "qwenVoiceNeil": "Presentador de notícies professional",
+    "qwenVoiceElias": "Instructor professional",
+    "qwenVoiceArthur": "Veu senzilla impregnada d'anys",
+    "qwenVoiceNini": "Veu suau i enganxosa",
+    "qwenVoiceEbona": "El seu murmuri és com una clau rovellada",
+    "qwenVoiceSeren": "Veu suau i relaxant per ajudar-vos a dormir",
+    "qwenVoicePip": "Entremaliat però ple d'innocència infantil",
+    "qwenVoiceStella": "Veu de noia dolça i confosa",
+    "qwenVoiceBodega": "Oncle espanyol entusiasta",
+    "qwenVoiceSonrisa": "Dona llatinoamericana entusiasta",
+    "qwenVoiceAlek": "Fred com una nació guerrera, càlid sota l'abric de llana",
+    "qwenVoiceDolce": "Oncle italià mandrós",
+    "qwenVoiceSohee": "Noia coreana amable i alegre",
+    "qwenVoiceOnoAnna": "Amic d'infància entremaliat",
+    "qwenVoiceLenn": "Jove alemany racional que porta vestit i escolta post-punk",
+    "qwenVoiceEmilien": "Germà gran francès romàntic",
+    "qwenVoiceAndre": "Veu masculina magnètica, natural i tranquil·la",
+    "qwenVoiceRadioGol": "Poeta del futbol Rádio Gol!",
+    "qwenVoiceJada": "Senyora de Shanghai animada",
+    "qwenVoiceDylan": "Noi de Pequín",
+    "qwenVoiceLi": "Professora de ioga pacient",
+    "qwenVoiceMarcus": "Cara ampla, paraules curtes, cor sòlid",
+    "qwenVoiceRoy": "Noi taiwanès humorístic i directe",
+    "qwenVoicePeter": "Suportador professional de comèdia Tianjin",
+    "qwenVoiceSunny": "Noia de Sichuan dolça",
+    "qwenVoiceEric": "Cavaller de Chengdu",
+    "qwenVoiceRocky": "Noi de Hong Kong humorístic",
+    "qwenVoiceKiki": "Noia de Hong Kong dolça",
+    "lang_auto": "Detecció automàtica",
+    "lang_zh": "中文",
+    "lang_yue": "粤語",
+    "lang_en": "English",
+    "lang_ja": "日本語",
+    "lang_ko": "한국어",
+    "lang_es": "Español",
+    "lang_fr": "Français",
+    "lang_de": "Deutsch",
+    "lang_ru": "Русский",
+    "lang_ar": "العربية",
+    "lang_pt": "Português",
+    "lang_it": "Italiano",
+    "lang_af": "Afrikaans",
+    "lang_hy": "Հայերեն",
+    "lang_az": "Azərbaycan",
+    "lang_be": "Беларуская",
+    "lang_bs": "Bosanski",
+    "lang_bg": "Български",
+    "lang_ca": "Català",
+    "lang_hr": "Hrvatski",
+    "lang_cs": "Čeština",
+    "lang_da": "Dansk",
+    "lang_nl": "Nederlands",
+    "lang_et": "Eesti",
+    "lang_fi": "Suomi",
+    "lang_gl": "Galego",
+    "lang_el": "Ελληνικά",
+    "lang_he": "עברית",
+    "lang_hi": "हिन्दी",
+    "lang_hu": "Magyar",
+    "lang_is": "Íslenska",
+    "lang_id": "Bahasa Indonesia",
+    "lang_kn": "ಕನ್ನಡ",
+    "lang_kk": "Қазақша",
+    "lang_lv": "Latviešu",
+    "lang_lt": "Lietuvių",
+    "lang_mk": "Македонски",
+    "lang_ms": "Bahasa Melayu",
+    "lang_mr": "मराठी",
+    "lang_mi": "Te Reo Māori",
+    "lang_ne": "नेपाली",
+    "lang_no": "Norsk",
+    "lang_fa": "فارسی",
+    "lang_pl": "Polski",
+    "lang_ro": "Română",
+    "lang_sr": "Српски",
+    "lang_sk": "Slovenčina",
+    "lang_sl": "Slovenščina",
+    "lang_sw": "Kiswahili",
+    "lang_sv": "Svenska",
+    "lang_tl": "Tagalog",
+    "lang_fil": "Filipino",
+    "lang_ta": "தமிழ்",
+    "lang_th": "ไทย",
+    "lang_tr": "Türkçe",
+    "lang_uk": "Українська",
+    "lang_ur": "اردو",
+    "lang_vi": "Tiếng Việt",
+    "lang_cy": "Cymraeg",
+    "lang_zh-CN": "中文（简体，中国）",
+    "lang_zh-TW": "中文（繁體，台灣）",
+    "lang_zh-HK": "粵語（香港）",
+    "lang_yue-Hant-HK": "粵語（繁體）",
+    "lang_en-US": "English (United States)",
+    "lang_en-GB": "English (United Kingdom)",
+    "lang_en-AU": "English (Australia)",
+    "lang_en-CA": "English (Canada)",
+    "lang_en-IN": "English (India)",
+    "lang_en-NZ": "English (New Zealand)",
+    "lang_en-ZA": "English (South Africa)",
+    "lang_ja-JP": "日本語（日本）",
+    "lang_ko-KR": "한국어（대한민국）",
+    "lang_de-DE": "Deutsch (Deutschland)",
+    "lang_fr-FR": "Français (France)",
+    "lang_es-ES": "Español (España)",
+    "lang_es-MX": "Español (México)",
+    "lang_es-AR": "Español (Argentina)",
+    "lang_es-CO": "Español (Colombia)",
+    "lang_it-IT": "Italiano (Italia)",
+    "lang_pt-BR": "Português (Brasil)",
+    "lang_pt-PT": "Português (Portugal)",
+    "lang_ru-RU": "Русский (Россия)",
+    "lang_nl-NL": "Nederlands (Nederland)",
+    "lang_pl-PL": "Polski (Polska)",
+    "lang_cs-CZ": "Čeština (Česko)",
+    "lang_da-DK": "Dansk (Danmark)",
+    "lang_fi-FI": "Suomi (Suomi)",
+    "lang_sv-SE": "Svenska (Sverige)",
+    "lang_no-NO": "Norsk (Norge)",
+    "lang_tr-TR": "Türkçe (Türkiye)",
+    "lang_el-GR": "Ελληνικά (Ελλάδα)",
+    "lang_hu-HU": "Magyar (Magyarország)",
+    "lang_ro-RO": "Română (România)",
+    "lang_sk-SK": "Slovenčina (Slovensko)",
+    "lang_bg-BG": "Български (България)",
+    "lang_hr-HR": "Hrvatski (Hrvatska)",
+    "lang_ca-ES": "Català (Espanya)",
+    "lang_ar-SA": "العربية (السعودية)",
+    "lang_ar-EG": "العربية (مصر)",
+    "lang_he-IL": "עברית (ישראל)",
+    "lang_hi-IN": "हिन्दी (भारत)",
+    "lang_th-TH": "ไทย (ประเทศไทย)",
+    "lang_vi-VN": "Tiếng Việt (Việt Nam)",
+    "lang_id-ID": "Bahasa Indonesia (Indonesia)",
+    "lang_ms-MY": "Bahasa Melayu (Malaysia)",
+    "lang_fil-PH": "Filipino (Pilipinas)",
+    "lang_af-ZA": "Afrikaans (Suid-Afrika)",
+    "lang_uk-UA": "Українська (Україна)",
+    "pdfSettings": "Anàlisi PDF",
+    "pdfParsingSettings": "Configuració d'anàlisi PDF",
+    "pdfDescription": "Trieu el motor d'anàlisi PDF amb suport per a l'extracció de text, processament d'imatges i reconeixement de taules",
+    "pdfProvider": "Analitzador PDF",
+    "pdfFeatures": "Funcions suportades",
+    "pdfApiKey": "Clau API",
+    "pdfBaseUrl": "Base URL",
+    "mineruDescription": "MinerU és un servei comercial d'anàlisi PDF que suporta funcions avançades com l'extracció de taules, el reconeixement de fórmules i l'anàlisi de disseny.",
+    "mineruApiKeyRequired": "Heu de sol·licitar una clau API al lloc web de MinerU abans d'usar-lo.",
+    "mineruWarning": "Avís",
+    "mineruCostWarning": "MinerU és un servei comercial i pot generar despeses. Consulteu el lloc web de MinerU per obtenir detalls de preus.",
+    "enterMinerUApiKey": "Introduïu la clau API de MinerU",
+    "mineruLocalDescription": "MinerU suporta desplegament local amb anàlisi PDF avançada (taules, fórmules, anàlisi de disseny). Requereix desplegar primer el servei MinerU.",
+    "mineruServerAddress": "Adreça del servidor MinerU local (p. ex., http://localhost:8080)",
+    "mineruApiKeyOptional": "Només necessari si el servidor té autenticació activada",
+    "optionalApiKey": "Clau API opcional",
+    "featureText": "Extracció de text",
+    "featureImages": "Extracció d'imatges",
+    "featureTables": "Extracció de taules",
+    "featureFormulas": "Reconeixement de fórmules",
+    "featureLayoutAnalysis": "Anàlisi de disseny",
+    "featureMetadata": "Metadades",
+    "enableImageGeneration": "Activar generació d'imatges IA",
+    "imageGenerationDisabledHint": "Quan s'activa, es generaran imatges automàticament durant la creació del curs",
+    "imageSettings": "Generació d'imatges",
+    "imageSection": "Text a imatge",
+    "imageProvider": "Proveïdor de generació d'imatges",
+    "imageModel": "Model de generació d'imatges",
+    "providerSeedream": "Seedream (ByteDance)",
+    "providerQwenImage": "Qwen Image (Alibaba)",
+    "providerNanoBanana": "Nano Banana (Gemini)",
+    "providerMiniMaxImage": "MiniMax Image",
+    "providerGrokImage": "Grok Image (xAI)",
+    "testImageGeneration": "Provar generació d'imatges",
+    "testImageConnectivity": "Provar connexió",
+    "imageConnectivitySuccess": "Servei d'imatges connectat correctament",
+    "imageConnectivityFailed": "Error en la connexió del servei d'imatges",
+    "imageTestSuccess": "Prova de generació d'imatges correcta",
+    "imageTestFailed": "Prova de generació d'imatges fallida",
+    "imageTestPromptPlaceholder": "Introduïu la descripció de la imatge per a la prova",
+    "imageTestPromptDefault": "Un gat maco assegut a un escriptori",
+    "imageGenerating": "Generant imatge...",
+    "imageGenerationFailed": "Error en la generació d'imatges",
+    "enableVideoGeneration": "Activar generació de vídeo IA",
+    "videoGenerationDisabledHint": "Quan s'activa, es generaran vídeos automàticament durant la creació del curs",
+    "videoSettings": "Generació de vídeo",
+    "videoSection": "Text a vídeo",
+    "videoProvider": "Proveïdor de generació de vídeo",
+    "videoModel": "Model de generació de vídeo",
+    "providerSeedance": "Seedance (ByteDance)",
+    "providerKling": "Kling (Kuaishou)",
+    "providerVeo": "Veo (Google)",
+    "providerSora": "Sora (OpenAI)",
+    "providerMiniMaxVideo": "MiniMax Video",
+    "providerGrokVideo": "Grok Video (xAI)",
+    "testVideoGeneration": "Provar generació de vídeo",
+    "testVideoConnectivity": "Provar connexió",
+    "videoConnectivitySuccess": "Servei de vídeo connectat correctament",
+    "videoConnectivityFailed": "Error en la connexió del servei de vídeo",
+    "testingConnection": "Provant...",
+    "videoTestSuccess": "Prova de generació de vídeo correcta",
+    "videoTestFailed": "Prova de generació de vídeo fallida",
+    "videoTestPromptDefault": "Un gat maco caminant per un escriptori",
+    "videoGenerating": "Generant vídeo (est. 1-2 min)...",
+    "videoGenerationWarning": "La generació de vídeo normalment triga 1-2 minuts, tingueu paciència",
+    "mediaRetry": "Reintentar",
+    "mediaContentSensitive": "Ho sentim, aquest contingut ha activat una verificació de seguretat.",
+    "mediaGenerationDisabled": "Generació desactivada a la configuració",
+    "singleAgent": "Agent únic",
+    "multiAgent": "Multi-agent",
+    "selectAgents": "Seleccionar agents",
+    "noVisionWarning": "El model actual no suporta visió. Les imatges es poden posar a les diapositives, però el model no pot entendre el contingut de les imatges per optimitzar la selecció i el disseny",
+    "serverConfigured": "Servidor",
+    "serverConfiguredNotice": "L'administrador ha configurat una clau API per a aquest proveïdor al servidor. Podeu usar-la directament o introduir la vostra pròpia clau per sobreescriure-la.",
+    "optionalOverride": "Opcional — deixeu buit per usar la configuració del servidor",
+    "setupNeeded": "Cal configuració",
+    "modelNotConfigured": "Seleccioneu un model per començar",
+    "dangerZone": "Zona de perill",
+    "clearCache": "Netejar caché local",
+    "clearCacheDescription": "Elimina totes les dades emmagatzemades localment, incloent registres d'aula, historial de xat, caché d'àudio i configuració de l'aplicació. Aquesta acció no es pot desfer.",
+    "clearCacheConfirmTitle": "Esteu segurs que voleu netejar tota la caché?",
+    "clearCacheConfirmDescription": "Això eliminarà permanentment totes les dades següents i no es podran recuperar:",
+    "clearCacheConfirmItems": "Aules i escenes, Historial de xat, Caché d'àudio i imatges, Configuració i preferències de l'aplicació",
+    "clearCacheConfirmInput": "Escriviu \"ELIMINAR\" per continuar",
+    "clearCacheConfirmPhrase": "ELIMINAR",
+    "clearCacheButton": "Eliminar permanentment totes les dades",
+    "clearCacheSuccess": "Caché netejada, la pàgina s'actualitzarà en breu",
+    "clearCacheFailed": "Error en netejar la caché, torneu-ho a intentar",
+    "generatedCourses": "Cursos generats",
+    "courseDirectory": "ID de directori",
+    "courseScenes": "Escenes",
+    "deleteCourse": "Eliminar",
+    "deleteCourseSuccess": "Curs eliminat",
+    "deleteCourseFailed": "Error en eliminar el curs, torneu-ho a intentar",
+    "noCoursesFound": "No hi ha cursos emmagatzemats",
+    "loadCoursesFailed": "Error carregant els cursos",
+    "webSearchSettings": "Cerca web",
+    "webSearchApiKey": "Clau API Tavily",
+    "webSearchApiKeyPlaceholder": "Introduïu la vostra clau API Tavily",
+    "webSearchApiKeyPlaceholderServer": "Clau del servidor configurada, podeu sobreescriure-la opcionalment",
+    "webSearchApiKeyHint": "Obteniu una clau API de tavily.com per a la cerca web",
+    "webSearchBaseUrl": "Base URL",
+    "webSearchServerConfigured": "La clau API Tavily del costat del servidor està configurada",
+    "optional": "Opcional",
+    "themesSettings": "Temes",
+    "themes": {
+      "title": "Temes",
+      "description": "Gestiona els temes visuals del material generat",
+      "active": "Actiu",
+      "activate": "Activa",
+      "export": "Exporta ZIP",
+      "upload": "Puja ZIP",
+      "delete": "Elimina",
+      "deleted": "Tema eliminat",
+      "imported": "Tema importat",
+      "confirmDelete": "Segur que vols eliminar aquest tema?",
+      "loadError": "No s'han pogut carregar els temes",
+      "deleteError": "No s'ha pogut eliminar el tema",
+      "exportError": "No s'ha pogut exportar el tema",
+      "importError": "No s'ha pogut importar el tema",
+      "loading": "Carregant...",
+      "builtIn": "incorporat"
+    }
+  },
+  "profile": {
+    "title": "Perfil",
+    "defaultNickname": "Estudiant",
+    "chooseAvatar": "Triar avatar",
+    "uploadAvatar": "Pujar",
+    "bioPlaceholder": "Expliqueu-nos alguna cosa de vosaltres — el professor IA personalitzarà les lliçons...",
+    "avatarHint": "El vostre avatar apareixerà a les discussions i xats de l'aula",
+    "fileTooLarge": "Imatge massa gran — trieu-ne una de menys de 5 MB",
+    "invalidFileType": "Seleccioneu un fitxer d'imatge",
+    "editTooltip": "Clic per editar el perfil"
+  },
+  "media": {
+    "imageCapability": "Generació d'imatges",
+    "imageHint": "Generar imatges a les diapositives",
+    "videoCapability": "Generació de vídeo",
+    "videoHint": "Generar vídeos a les diapositives",
+    "ttsCapability": "Síntesi de veu",
+    "ttsHint": "El professor IA parla en veu alta",
+    "asrCapability": "Reconeixement de veu",
+    "asrHint": "Entrada de veu per a la discussió",
+    "provider": "Proveïdor",
+    "model": "Model",
+    "voice": "Veu",
+    "speed": "Velocitat",
+    "language": "Idioma"
+  },
+  "email": {
+    "common": {
+      "urlFallbackLabel": "Si el botó no funciona, copia aquest URL al teu navegador:",
+      "footer": "OpenMAIC — Plataforma open source sota llicència AGPL-3.0"
+    },
+    "invitation": {
+      "subject": "{{inviterName}} t'ha convidat a OpenMAIC",
+      "subtitle": "Aula Interactiva amb IA",
+      "greeting": "Hola, {{displayName}}!",
+      "body1": "{{inviterName}} t'ha convidat a unir-te a OpenMAIC, la plataforma d'aules interactives amb intel·ligència artificial.",
+      "body2": "Clica el botó a continuació per completar el teu registre i activar el compte.",
+      "cta": "Acceptar invitació",
+      "ttlNotice": "Aquest enllaç és vàlid durant {{hours}} hores.",
+      "plainBody": "{{inviterName}} t'ha convidat a unir-te a OpenMAIC, la plataforma d'aules interactives amb IA.",
+      "plainCta": "Per completar el teu registre, accedeix a:",
+      "ignore": "Si no esperaves aquesta invitació, pots ignorar aquest missatge."
+    },
+    "passwordReset": {
+      "subject": "OpenMAIC — Sol·licitud de canvi de contrasenya",
+      "greeting": "Hola, {{firstName}}!",
+      "body": "Hem rebut una sol·licitud per canviar la contrasenya del teu compte d'OpenMAIC. Si no has estat tu, pots ignorar aquest correu i la contrasenya no canviarà.",
+      "cta": "Canviar la contrasenya",
+      "ttlNotice": "Aquest enllaç és vàlid durant {{hours}} hores.",
+      "plainCta": "Per canviar la contrasenya, accedeix a:",
+      "ignore": "Si no has sol·licitat cap canvi de contrasenya, pots ignorar aquest missatge."
+    }
+  },
+  "auth": {
+    "acceptInvite": {
+      "verifying": "Verificant invitació...",
+      "invalidTitle": "Invitació no vàlida",
+      "noToken": "No s'ha proporcionat cap token d'invitació.",
+      "invalidToken": "Token d'invitació no vàlid o caducat.",
+      "connectionError": "Error de connexió. Torna-ho a intentar.",
+      "title": "Completa el teu registre",
+      "description": "Benvingut/da, {{name}}! Configura la contrasenya per activar el teu compte.",
+      "firstName": "Nom",
+      "lastName": "Cognom",
+      "email": "Correu electrònic",
+      "password": "Contrasenya (mínim 8 caràcters)",
+      "passwordConfirm": "Confirma la contrasenya",
+      "passwordMinLength": "La contrasenya ha de tenir mínim 8 caràcters.",
+      "passwordMismatch": "Les contrasenyes no coincideixen.",
+      "profileOptional": "Informació del perfil (opcional)",
+      "organization": "Organització",
+      "organizationPlaceholder": "Universitat, empresa, institució...",
+      "department": "Departament",
+      "city": "Ciutat",
+      "jobTitle": "Càrrec",
+      "jobTitlePlaceholder": "Professor/a, investigador/a, tècnic/a...",
+      "activating": "Activant compte...",
+      "activate": "Activar compte",
+      "activateError": "Error activant el compte. Torna-ho a intentar."
+    },
+    "resetPassword": {
+      "verifying": "Verificant l'enllaç...",
+      "invalidTitle": "Enllaç no vàlid",
+      "noToken": "L'enllaç no és vàlid.",
+      "expired": "L'enllaç ha caducat. Sol·licita'n un de nou.",
+      "invalidOrUsed": "L'enllaç no és vàlid o ja ha estat utilitzat.",
+      "connectionError": "Error de connexió. Torna-ho a intentar.",
+      "requestNew": "Sol·licitar un nou enllaç",
+      "backToLogin": "Tornar a l'accés",
+      "doneTitle": "Contrasenya canviada",
+      "doneDescription": "La teva contrasenya s'ha actualitzat correctament. Seràs redirigit a l'accés en uns moments.",
+      "loginNow": "Accedir ara",
+      "title": "Nova contrasenya",
+      "emailDescription": "Canvia la contrasenya de {{email}}",
+      "password": "Nova contrasenya",
+      "passwordHint": "Mínim 8 caràcters.",
+      "confirmPassword": "Confirmar contrasenya",
+      "mismatchInline": "Les contrasenyes no coincideixen.",
+      "passwordMinLength": "La contrasenya ha de tenir mínim 8 caràcters.",
+      "passwordMismatch": "Les contrasenyes no coincideixen.",
+      "changeError": "Error en canviar la contrasenya.",
+      "saving": "Desant...",
+      "submit": "Canviar la contrasenya"
+    }
+  }
+}
diff --git a/lib/i18n/locales/en-US.json b/lib/i18n/locales/en-US.json
index 997857983..89401dfc5 100644
--- a/lib/i18n/locales/en-US.json
+++ b/lib/i18n/locales/en-US.json
@@ -117,7 +117,49 @@
     "confirmSwitchMessage": "A topic is currently in progress. Switching scenes will end the current topic. Are you sure?",
     "generatingNextPage": "Scene is being generated, please wait...",
     "fullscreen": "Fullscreen",
-    "exitFullscreen": "Exit Fullscreen"
+    "exitFullscreen": "Exit Fullscreen",
+    "regen": {
+      "dialogTitle": "Regenerate",
+      "indication": "Indication",
+      "indicationPlaceholder": "Describe what this slide should cover…",
+      "audioText": "Audio text",
+      "audioTextPlaceholder": "Narration text for this slide…",
+      "media": "Media",
+      "mediaNone": "None",
+      "mediaKeep": "Keep",
+      "mediaImage": "Image",
+      "mediaVideo": "Video",
+      "generatingPrompt": "Generating prompt…",
+      "promptOriginal": "Original prompt loaded. You can modify it.",
+      "promptAutoGenerated": "Auto-generated prompt. Edit if needed.",
+      "mediaPromptPlaceholder": "Describe the image or video…",
+      "theme": "Theme",
+      "cancel": "Cancel",
+      "regenerate": "Regenerate",
+      "reviewBar": "Regenerated version — pending acceptance",
+      "accept": "Accept",
+      "undo": "Undo",
+      "editAgain": "Edit again",
+      "confirmTitle": "Keep new version?",
+      "confirmBody": "Slide \"{title}\" has a regenerated version pending acceptance. If you switch slides without accepting, the new version will be discarded.",
+      "confirmKeep": "Yes, keep",
+      "confirmDiscard": "Discard",
+      "buttonLabel": "↺ Regen.",
+      "inProgress": "Regenerating slide…",
+      "stepContent": "Generating content…",
+      "stepAudio": "Generating audio…",
+      "stepMedia": "Generating media…",
+      "modifyAudio": "Modify narration",
+      "modifySlide": "Modify slide",
+      "slideTitle": "Title",
+      "slideKeep": "Existing slide will be preserved.",
+      "slideWarningMediaNeeded": "To add new image/video, the slide must also be regenerated.",
+      "audioKeep": "Existing narration will be preserved — no new audio generated.",
+      "generateNarration": "Generate with AI",
+      "generatingNarration": "Generating narration…",
+      "aiGenerationError": "Generation failed.",
+      "aiModelHint": "Select an LLM model using the controls at the bottom left."
+    }
   },
   "whiteboard": {
     "title": "Interactive Whiteboard",
diff --git a/lib/i18n/locales/ja-JP.json b/lib/i18n/locales/ja-JP.json
index 6d82ebf07..e92fb8b28 100644
--- a/lib/i18n/locales/ja-JP.json
+++ b/lib/i18n/locales/ja-JP.json
@@ -117,7 +117,49 @@
     "confirmSwitchMessage": "現在トピックが進行中です。シーンを切り替えると、現在のトピックが終了します。よろしいですか？",
     "generatingNextPage": "シーンを生成中です。お待ちください...",
     "fullscreen": "全画面表示",
-    "exitFullscreen": "全画面表示を終了"
+    "exitFullscreen": "全画面表示を終了",
+    "regen": {
+      "dialogTitle": "再生成",
+      "indication": "指示",
+      "indicationPlaceholder": "このスライドでカバーすべき内容を説明してください…",
+      "audioText": "音声テキスト",
+      "audioTextPlaceholder": "このスライドのナレーションテキスト…",
+      "media": "メディア",
+      "mediaNone": "なし",
+      "mediaKeep": "維持",
+      "mediaImage": "画像",
+      "mediaVideo": "動画",
+      "generatingPrompt": "プロンプトを生成中…",
+      "promptOriginal": "元のプロンプトを読み込みました。変更できます。",
+      "promptAutoGenerated": "自動生成されたプロンプトです。必要に応じて編集してください。",
+      "mediaPromptPlaceholder": "画像または動画を説明してください…",
+      "theme": "テーマ",
+      "cancel": "キャンセル",
+      "regenerate": "再生成",
+      "reviewBar": "再生成されたバージョン — 承認待ち",
+      "accept": "承認",
+      "undo": "元に戻す",
+      "editAgain": "再編集",
+      "confirmTitle": "新しいバージョンを保持しますか？",
+      "confirmBody": "スライド\"{title}\"には承認待ちの再生成バージョンがあります。承認せずにスライドを切り替えると、新しいバージョンは破棄されます。",
+      "confirmKeep": "はい、保持する",
+      "confirmDiscard": "破棄",
+      "buttonLabel": "↺ 再生成",
+      "inProgress": "スライドを再生成中…",
+      "stepContent": "コンテンツを生成中…",
+      "stepAudio": "音声を生成中…",
+      "stepMedia": "メディアを生成中…",
+      "modifyAudio": "ナレーションを変更",
+      "modifySlide": "スライドを変更",
+      "slideTitle": "タイトル",
+      "slideKeep": "既存のスライドが保持されます。",
+      "slideWarningMediaNeeded": "新しい画像/動画を追加するには、スライドも再生成する必要があります。",
+      "audioKeep": "既存のナレーションが保持されます — 新しい音声は生成されません。",
+      "generateNarration": "AIで生成",
+      "generatingNarration": "ナレーション生成中…",
+      "aiGenerationError": "生成に失敗しました。",
+      "aiModelHint": "左下のコントロールでLLMモデルを選択してください。"
+    }
   },
   "whiteboard": {
     "title": "インタラクティブホワイトボード",
diff --git a/lib/i18n/locales/ru-RU.json b/lib/i18n/locales/ru-RU.json
index 9afa76e68..e0ee07ebd 100644
--- a/lib/i18n/locales/ru-RU.json
+++ b/lib/i18n/locales/ru-RU.json
@@ -117,7 +117,49 @@
     "confirmSwitchMessage": "В данный момент идёт обсуждение. Переключение сцены завершит текущую тему. Продолжить?",
     "generatingNextPage": "Сцена генерируется, пожалуйста подождите...",
     "fullscreen": "Полный экран",
-    "exitFullscreen": "Свернуть"
+    "exitFullscreen": "Свернуть",
+    "regen": {
+      "dialogTitle": "Регенерация",
+      "indication": "Указание",
+      "indicationPlaceholder": "Опишите, что должен охватывать этот слайд…",
+      "audioText": "Текст для аудио",
+      "audioTextPlaceholder": "Текст narration для этого слайда…",
+      "media": "Медиа",
+      "mediaNone": "Нет",
+      "mediaKeep": "Сохранить",
+      "mediaImage": "Изображение",
+      "mediaVideo": "Видео",
+      "generatingPrompt": "Генерация промпта…",
+      "promptOriginal": "Загружен исходный промпт. Можно изменить.",
+      "promptAutoGenerated": "Промпт сгенерирован автоматически. При необходимости отредактируйте.",
+      "mediaPromptPlaceholder": "Опишите изображение или видео…",
+      "theme": "Тема",
+      "cancel": "Отмена",
+      "regenerate": "Регенерировать",
+      "reviewBar": "Регенерированная версия — ожидает подтверждения",
+      "accept": "Принять",
+      "undo": "Отменить",
+      "editAgain": "Редактировать снова",
+      "confirmTitle": "Сохранить новую версию?",
+      "confirmBody": "Слайд \"{title}\" имеет регенерированную версию, ожидающую подтверждения. Если переключить слайды без принятия, новая версия будет удалена.",
+      "confirmKeep": "Да, сохранить",
+      "confirmDiscard": "Отказаться",
+      "buttonLabel": "↺ Рег.",
+      "inProgress": "Регенерация слайда…",
+      "stepContent": "Генерация контента…",
+      "stepAudio": "Генерация аудио…",
+      "stepMedia": "Генерация медиа…",
+      "modifyAudio": "Изменить нарратив",
+      "modifySlide": "Изменить слайд",
+      "slideTitle": "Заголовок",
+      "slideKeep": "Существующий слайд будет сохранён.",
+      "slideWarningMediaNeeded": "Для добавления нового изображения/видео слайд также будет регенерирован.",
+      "audioKeep": "Существующий нарратив будет сохранён — новое аудио не создаётся.",
+      "generateNarration": "Сгенерировать с ИИ",
+      "generatingNarration": "Генерация нарратива…",
+      "aiGenerationError": "Ошибка генерации.",
+      "aiModelHint": "Выберите LLM-модель в элементах управления внизу слева."
+    }
   },
   "whiteboard": {
     "title": "Интерактивная доска",
@@ -690,7 +732,6 @@
     "lang_fa": "فارسی",
     "lang_pl": "Polski",
     "lang_ro": "Română",
-    "lang_ru": "Русский",
     "lang_sr": "Српски",
     "lang_sk": "Slovenčina",
     "lang_sl": "Slovenščina",
diff --git a/lib/i18n/locales/zh-CN.json b/lib/i18n/locales/zh-CN.json
index b2f7a2a79..6437dcefc 100644
--- a/lib/i18n/locales/zh-CN.json
+++ b/lib/i18n/locales/zh-CN.json
@@ -117,7 +117,49 @@
     "confirmSwitchMessage": "当前话题正在进行中，切换页面将结束当前话题。确定要切换吗？",
     "generatingNextPage": "场景正在生成，请稍候...",
     "fullscreen": "全屏",
-    "exitFullscreen": "退出全屏"
+    "exitFullscreen": "退出全屏",
+    "regen": {
+      "dialogTitle": "重新生成",
+      "indication": "说明",
+      "indicationPlaceholder": "描述此幻灯片应涵盖的内容…",
+      "audioText": "音频文本",
+      "audioTextPlaceholder": "此幻灯片的旁白文本…",
+      "media": "媒体",
+      "mediaNone": "无",
+      "mediaKeep": "保留",
+      "mediaImage": "图片",
+      "mediaVideo": "视频",
+      "generatingPrompt": "正在生成提示词…",
+      "promptOriginal": "已加载原始提示词，可以修改。",
+      "promptAutoGenerated": "自动生成的提示词，可按需编辑。",
+      "mediaPromptPlaceholder": "描述图片或视频…",
+      "theme": "主题",
+      "cancel": "取消",
+      "regenerate": "重新生成",
+      "reviewBar": "已重新生成 — 等待确认",
+      "accept": "接受",
+      "undo": "撤销",
+      "editAgain": "重新编辑",
+      "confirmTitle": "保留新版本？",
+      "confirmBody": "幻灯片\"{title}\"有一个待确认的重新生成版本。如果切换幻灯片而不接受，新版本将被丢弃。",
+      "confirmKeep": "是，保留",
+      "confirmDiscard": "放弃",
+      "buttonLabel": "↺ 重新生成",
+      "inProgress": "正在重新生成幻灯片…",
+      "stepContent": "正在生成内容…",
+      "stepAudio": "正在生成音频…",
+      "stepMedia": "正在生成媒体…",
+      "modifyAudio": "修改旁白",
+      "modifySlide": "修改幻灯片",
+      "slideTitle": "标题",
+      "slideKeep": "现有幻灯片将被保留。",
+      "slideWarningMediaNeeded": "添加新图片/视频时，幻灯片也将被重新生成。",
+      "audioKeep": "将保留现有旁白 — 不会生成新音频。",
+      "generateNarration": "用AI生成",
+      "generatingNarration": "正在生成旁白…",
+      "aiGenerationError": "生成失败。",
+      "aiModelHint": "请在左下角控件中选择一个LLM模型。"
+    }
   },
   "whiteboard": {
     "title": "互动白板",
diff --git a/lib/media/adapters/kling-adapter.ts b/lib/media/adapters/kling-adapter.ts
index f47e10c02..a487de686 100644
--- a/lib/media/adapters/kling-adapter.ts
+++ b/lib/media/adapters/kling-adapter.ts
@@ -162,7 +162,8 @@ async function submitTask(
   const body: Record<string, unknown> = {
     model_name: model,
     prompt: options.prompt,
-    negative_prompt: '',
+    // Explicitly exclude audio from negative prompt — audio is handled via TTS
+    negative_prompt: 'audio, sound, music, voice, narration',
     mode: 'pro',
   };
 
diff --git a/lib/media/adapters/veo-adapter.ts b/lib/media/adapters/veo-adapter.ts
index aa6169704..e3a634ebb 100644
--- a/lib/media/adapters/veo-adapter.ts
+++ b/lib/media/adapters/veo-adapter.ts
@@ -1,27 +1,25 @@
 /**
  * Veo (Google) Video Generation Adapter
  *
- * Direct REST API calls for video generation with Google's Veo models.
- * Async task pattern: submit → poll → return inline base64 video.
+ * Uses @ai-sdk/google provider + experimental_generateVideo from 'ai'.
+ * The SDK handles the submit/poll lifecycle correctly against the Gemini API.
  *
- * REST endpoints (Gemini API):
- * - Submit:   POST /v1beta/models/{model}:predictLongRunning
- * - Poll:     POST /v1beta/models/{model}:fetchPredictOperation  { operationName }
- *   Returns inline base64 video data in response.videos[]
+ * Supported models (Gemini API, API key auth):
+ * - veo-3.1-fast-generate-preview  (fast)
+ * - veo-3.1-generate-preview       (quality)
+ * - veo-3.1-generate               (stable)
+ * - veo-3.0-fast-generate-001      (fast)
+ * - veo-3.0-generate-001           (quality)
+ * - veo-2.0-generate-001           (legacy)
  *
- * Supported models:
- * - veo-3.1-fast-generate-001  (fast, $0.15/sec)
- * - veo-3.1-generate-001       (quality, $0.40/sec)
- * - veo-3.0-fast-generate-001  (fast, $0.15/sec)
- * - veo-3.0-generate-001       (quality, $0.40/sec)
- * - veo-2.0-generate-001       (legacy, $0.50/sec)
- *
- * Authentication: x-goog-api-key header
+ * Authentication: Google AI Studio API key (x-goog-api-key)
  *
  * Stateless: video content is returned as a base64 data URL.
  * No files are saved on the server.
  */
 
+import { createGoogleGenerativeAI } from '@ai-sdk/google';
+import { experimental_generateVideo } from 'ai';
 import type {
   VideoGenerationConfig,
   VideoGenerationOptions,
@@ -30,18 +28,9 @@ import type {
 
 const DEFAULT_MODEL = 'veo-3.0-generate-001';
 const DEFAULT_BASE_URL = 'https://generativelanguage.googleapis.com';
-const POLL_INTERVAL_MS = 10_000; // 10 seconds
-const MAX_POLL_ATTEMPTS = 60; // 10 minutes max
-
-function delay(ms: number): Promise<void> {
-  return new Promise((resolve) => setTimeout(resolve, ms));
-}
 
 /** Dimension defaults per aspect ratio */
-function getDimensions(aspectRatio?: string): {
-  width: number;
-  height: number;
-} {
+function getDimensions(aspectRatio?: string): { width: number; height: number } {
   switch (aspectRatio) {
     case '9:16':
       return { width: 720, height: 1280 };
@@ -54,141 +43,36 @@ function getDimensions(aspectRatio?: string): {
   }
 }
 
-/** Common headers for all Veo API calls */
-function apiHeaders(apiKey: string): Record<string, string> {
-  return {
-    'Content-Type': 'application/json',
-    'x-goog-api-key': apiKey,
-  };
-}
-
-// ---------------------------------------------------------------------------
-// REST types (matches official Gemini API response format)
-// ---------------------------------------------------------------------------
-
-interface VeoOperation {
-  name: string;
-  done?: boolean;
-  response?: {
-    /** fetchPredictOperation returns inline base64 video data */
-    videos?: Array<{
-      bytesBase64Encoded?: string; // base64-encoded video bytes
-      mimeType?: string; // e.g. "video/mp4"
-    }>;
-  };
-  error?: { code: number; message: string; status: string };
-}
-
-// ---------------------------------------------------------------------------
-// Submit
-// ---------------------------------------------------------------------------
-
-async function submitVideoGeneration(
-  baseUrl: string,
-  apiKey: string,
-  model: string,
-  options: VideoGenerationOptions,
-): Promise<VeoOperation> {
-  const url = `${baseUrl}/v1beta/models/${model}:predictLongRunning`;
-
-  const body: Record<string, unknown> = {
-    instances: [{ prompt: options.prompt }],
-  };
-
-  // Parameters are optional — only include if we have values
-  const parameters: Record<string, unknown> = {};
-  if (options.aspectRatio) parameters.aspectRatio = options.aspectRatio;
-  if (options.duration) parameters.durationSeconds = options.duration;
-  if (Object.keys(parameters).length > 0) {
-    body.parameters = parameters;
-  }
-
-  const response = await fetch(url, {
-    method: 'POST',
-    headers: apiHeaders(apiKey),
-    body: JSON.stringify(body),
-  });
-
-  if (!response.ok) {
-    const text = await response.text();
-    throw new Error(`Veo submit failed (${response.status}): ${text}`);
-  }
-
-  return response.json() as Promise<VeoOperation>;
-}
-
-// ---------------------------------------------------------------------------
-// Poll
-// ---------------------------------------------------------------------------
-
-async function pollOperation(
-  baseUrl: string,
-  apiKey: string,
-  model: string,
-  operationName: string,
-): Promise<VeoOperation> {
-  const url = `${baseUrl}/v1beta/models/${model}:fetchPredictOperation`;
-
-  const response = await fetch(url, {
-    method: 'POST',
-    headers: apiHeaders(apiKey),
-    body: JSON.stringify({ operationName }),
-  });
-
-  if (!response.ok) {
-    const text = await response.text();
-    throw new Error(`Veo poll failed (${response.status}): ${text}`);
-  }
-
-  return response.json() as Promise<VeoOperation>;
-}
-
-// ---------------------------------------------------------------------------
-// Public entry point
-// ---------------------------------------------------------------------------
-
 /**
- * Lightweight connectivity test — validates API key by fetching model info.
- * Uses GET /v1beta/models/{model} which does not trigger generation.
+ * Lightweight connectivity test — validates API key by listing models.
+ * Uses GET /v1beta/models?key=... which does not trigger generation.
  */
 export async function testVeoConnectivity(
   config: VideoGenerationConfig,
 ): Promise<{ success: boolean; message: string }> {
   const model = config.model || DEFAULT_MODEL;
   const baseUrl = config.baseUrl || DEFAULT_BASE_URL;
-  const url = `${baseUrl}/v1beta/models`;
+  const url = `${baseUrl}/v1beta/models?key=${config.apiKey}`;
 
-  // Try ?key= query param first (direct Google API), fall back to x-goog-api-key header (proxy)
-  let response: Response | null = null;
+  let response: Response;
   try {
-    response = await fetch(`${url}?key=${config.apiKey}`, { method: 'GET' });
+    response = await fetch(url, { method: 'GET' });
   } catch {
-    // Direct API unreachable, try header auth
-  }
-  if (!response || !response.ok) {
-    try {
-      response = await fetch(url, {
-        method: 'GET',
-        headers: { 'x-goog-api-key': config.apiKey },
-      });
-    } catch (_err) {
-      return {
-        success: false,
-        message: `Network error: unable to reach ${baseUrl}. Check your Base URL and network connection.`,
-      };
-    }
+    return {
+      success: false,
+      message: `Network error: unable to reach ${baseUrl}. Check your Base URL and network connection.`,
+    };
   }
 
   if (response.ok) {
     return { success: true, message: `Connected to Veo (${model})` };
   }
 
-  // Parse error body for user-friendly message
   const text = await response.text().catch(() => '');
   if (response.status === 400 || response.status === 401 || response.status === 403) {
     return {
       success: false,
-      message: `Invalid API key or unauthorized (${response.status}). Check your API Key and Base URL match the same provider.`,
+      message: `Invalid API key or unauthorized (${response.status}). Check your API Key and Base URL.`,
     };
   }
   return {
@@ -202,51 +86,51 @@ export async function generateWithVeo(
   options: VideoGenerationOptions,
 ): Promise<VideoGenerationResult> {
   const model = config.model || DEFAULT_MODEL;
-  const baseUrl = config.baseUrl || DEFAULT_BASE_URL;
-
-  // 1. Submit
-  const operation = await submitVideoGeneration(baseUrl, config.apiKey, model, options);
 
-  if (!operation.name) {
-    throw new Error('Veo returned operation without name');
-  }
-
-  // 2. Poll until done
-  let current = operation;
-  let pollCount = 0;
-  while (!current.done) {
-    if (pollCount >= MAX_POLL_ATTEMPTS) {
-      throw new Error('Veo video generation timed out after 10 minutes');
-    }
-    await delay(POLL_INTERVAL_MS);
-    current = await pollOperation(baseUrl, config.apiKey, model, current.name);
-    pollCount++;
-  }
+  const google = createGoogleGenerativeAI({
+    apiKey: config.apiKey,
+    baseURL: config.baseUrl,
+  });
 
-  // 3. Check for errors
-  if (current.error) {
-    throw new Error(`Veo generation failed: ${current.error.code} - ${current.error.message}`);
-  }
+  // Only Veo 3+ non-fast models expose the generateAudio parameter.
+  // Fast variants and Veo 2.0 reject it at the API level, so we gate it.
+  const supportsAudioParam = !model.includes('fast') && !model.startsWith('veo-2');
+
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  const result = await experimental_generateVideo({
+    model: google.video(model as Parameters<typeof google.video>[0]),
+    prompt: options.prompt,
+    ...(options.aspectRatio && { aspectRatio: options.aspectRatio as `${number}:${number}` }),
+    ...(options.duration && { duration: options.duration }),
+    // Disable audio generation on models that support it — audio is handled via TTS.
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    ...(supportsAudioParam && { providerOptions: { google: { generateAudio: false } } as any }),
+  });
 
-  // 4. Extract inline base64 video from response.videos[]
-  const videos = current.response?.videos;
-  if (!videos || videos.length === 0) {
+  const video = result.videos[0];
+  if (!video) {
     throw new Error('Veo returned no generated videos');
   }
 
-  const first = videos[0];
-  if (!first.bytesBase64Encoded) {
-    throw new Error('Veo returned video entry without data');
+  // Convert to data URL — SDK may return base64, binary (Uint8Array) or URL
+  let url: string;
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  const v = video as any;
+  if (v.base64) {
+    url = `data:${v.mediaType ?? 'video/mp4'};base64,${v.base64}`;
+  } else if (v.uint8Array) {
+    const b64 = Buffer.from(v.uint8Array as Uint8Array).toString('base64');
+    url = `data:${v.mediaType ?? 'video/mp4'};base64,${b64}`;
+  } else if (v.url) {
+    url = v.url as string;
+  } else {
+    throw new Error('Veo returned video in unexpected format');
   }
 
-  const base64 = first.bytesBase64Encoded;
-  const mimeType = first.mimeType || 'video/mp4';
-
   const { width, height } = getDimensions(options.aspectRatio);
-
   return {
-    url: `data:${mimeType};base64,${base64}`,
-    duration: options.duration || 8,
+    url,
+    duration: options.duration ?? 8,
     width,
     height,
   };
diff --git a/lib/media/media-orchestrator.ts b/lib/media/media-orchestrator.ts
index 151a3acab..f833019ea 100644
--- a/lib/media/media-orchestrator.ts
+++ b/lib/media/media-orchestrator.ts
@@ -59,7 +59,7 @@ export async function generateMediaForOutlines(
   // Process requests serially — image/video APIs have limited concurrency
   for (const req of allRequests) {
     if (abortSignal?.aborted) break;
-    await generateSingleMedia(req, stageId, abortSignal);
+    await generateAndStoreMedia(req, stageId, abortSignal);
   }
 }
 
@@ -87,7 +87,7 @@ export async function retryMediaTask(elementId: string): Promise<void> {
   await db.mediaFiles.delete(dbKey).catch(() => {});
 
   store.markPendingForRetry(elementId);
-  await generateSingleMedia(
+  await generateAndStoreMedia(
     {
       type: task.type,
       prompt: task.prompt,
@@ -99,9 +99,14 @@ export async function retryMediaTask(elementId: string): Promise<void> {
   );
 }
 
-// ==================== Internal ====================
+// ==================== Exported core ====================
 
-async function generateSingleMedia(
+/**
+ * Generate a single media item (image or video) and persist it to the server.
+ * Updates the media generation store on completion or failure.
+ * Exported for use by the per-slide regeneration flow.
+ */
+export async function generateAndStoreMedia(
   req: MediaGenerationRequest,
   stageId: string,
   abortSignal?: AbortSignal,
@@ -183,6 +188,8 @@ async function generateSingleMedia(
   }
 }
 
+// ==================== Internal helpers ====================
+
 async function callImageApi(
   req: MediaGenerationRequest,
   abortSignal?: AbortSignal,
diff --git a/lib/media/video-providers.ts b/lib/media/video-providers.ts
index cf9e4562a..d5d2ec205 100644
--- a/lib/media/video-providers.ts
+++ b/lib/media/video-providers.ts
@@ -169,6 +169,13 @@ export function normalizeVideoOptions(
     }
   }
 
+  // Videos are always silent — audio is handled separately via TTS.
+  // Append a no-audio instruction to the prompt so all providers produce muted output.
+  const NO_AUDIO_SUFFIX = ', no audio, no sound, no music, silent video loop';
+  if (!normalized.prompt.includes('no audio')) {
+    normalized.prompt = normalized.prompt + NO_AUDIO_SUFFIX;
+  }
+
   return normalized;
 }
 
diff --git a/lib/store/media-generation.ts b/lib/store/media-generation.ts
index b64e1ae2d..5cc1f247e 100644
--- a/lib/store/media-generation.ts
+++ b/lib/store/media-generation.ts
@@ -49,6 +49,9 @@ interface MediaGenerationState {
   // Retry support
   markPendingForRetry: (elementId: string) => void;
 
+  // Reset a single task (removes it from the store so it can be re-enqueued fresh)
+  resetTask: (elementId: string) => void;
+
   // Queries
   getTask: (elementId: string) => MediaTask | undefined;
   isReady: (elementId: string) => boolean;
@@ -153,6 +156,12 @@ export const useMediaGenerationStore = create<MediaGenerationState>()((set, get)
       };
     }),
 
+  resetTask: (elementId) =>
+    set((s) => {
+      const { [elementId]: _, ...rest } = s.tasks;
+      return { tasks: rest };
+    }),
+
   getTask: (elementId) => get().tasks[elementId],
 
   isReady: (elementId) => get().tasks[elementId]?.status === 'done',
diff --git a/tests/api/media-prompt.test.ts b/tests/api/media-prompt.test.ts
new file mode 100644
index 000000000..a68d17bd5
--- /dev/null
+++ b/tests/api/media-prompt.test.ts
@@ -0,0 +1,57 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+
+vi.mock('@/lib/ai/llm', () => ({
+  callLLM: vi.fn().mockResolvedValue({ text: 'A diagram showing React components' }),
+}));
+
+vi.mock('@/lib/server/resolve-model', () => ({
+  resolveModelFromHeaders: vi.fn().mockResolvedValue({
+    model: {},
+    modelInfo: {},
+    modelString: 'test-model',
+  }),
+}));
+
+describe('POST /api/generate/media-prompt', () => {
+  beforeEach(() => vi.clearAllMocks());
+
+  it('returns a generated prompt string', async () => {
+    const { POST } = await import('@/app/api/generate/media-prompt/route');
+    const req = new Request('http://localhost/api/generate/media-prompt', {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json', 'x-model': 'test-model' },
+      body: JSON.stringify({
+        indicationText: 'React components: props, state, re-render',
+        mediaType: 'image',
+        language: 'en-US',
+      }),
+    });
+    const res = await POST(req as never);
+    const data = await res.json();
+    expect(data.success).toBe(true);
+    expect(typeof data.data.prompt).toBe('string');
+    expect(data.data.prompt.length).toBeGreaterThan(0);
+  });
+
+  it('returns 400 when indicationText is missing', async () => {
+    const { POST } = await import('@/app/api/generate/media-prompt/route');
+    const req = new Request('http://localhost/api/generate/media-prompt', {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ mediaType: 'image' }),
+    });
+    const res = await POST(req as never);
+    expect(res.status).toBe(400);
+  });
+
+  it('returns 400 when mediaType is invalid', async () => {
+    const { POST } = await import('@/app/api/generate/media-prompt/route');
+    const req = new Request('http://localhost/api/generate/media-prompt', {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ indicationText: 'Some text', mediaType: 'gif' }),
+    });
+    const res = await POST(req as never);
+    expect(res.status).toBe(400);
+  });
+});
diff --git a/tests/api/scene-content-only.test.ts b/tests/api/scene-content-only.test.ts
new file mode 100644
index 000000000..61dfefa09
--- /dev/null
+++ b/tests/api/scene-content-only.test.ts
@@ -0,0 +1,157 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+
+const defaultLoadStage = vi.fn().mockResolvedValue({
+  stage: { id: 'stage1', name: 'Test Stage', language: 'en-US' },
+});
+const defaultLoadOutlines = vi
+  .fn()
+  .mockResolvedValue([
+    { id: 'o1', type: 'slide', title: 'Slide 1', description: 'Desc', keyPoints: [], order: 1 },
+  ]);
+
+// Mock storage backend
+vi.mock('@/lib/server/storage', () => ({
+  getStorageBackend: vi.fn(() => ({
+    loadStage: defaultLoadStage,
+    loadOutlines: defaultLoadOutlines,
+  })),
+}));
+
+// Mock generateSceneContentFromInput
+vi.mock('@/lib/server/scene-content-generation', () => ({
+  generateSceneContentFromInput: vi.fn().mockResolvedValue({
+    content: { elements: [{ id: 'el1', type: 'text' }], background: undefined },
+    effectiveOutline: {
+      id: 'o1',
+      type: 'slide',
+      title: 'Slide 1',
+      description: 'Desc',
+      keyPoints: [],
+      order: 1,
+    },
+    slideTheme: undefined,
+  }),
+}));
+
+vi.mock('@/lib/server/resolve-model', () => ({
+  resolveModelFromHeaders: vi.fn().mockResolvedValue({
+    model: {},
+    modelInfo: {},
+    modelString: 'test-model',
+  }),
+}));
+
+describe('POST /api/generate/scene-content-only', () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+    // Restore default storage mock implementation after each test
+    defaultLoadStage.mockResolvedValue({
+      stage: { id: 'stage1', name: 'Test Stage', language: 'en-US' },
+    });
+    defaultLoadOutlines.mockResolvedValue([
+      { id: 'o1', type: 'slide', title: 'Slide 1', description: 'Desc', keyPoints: [], order: 1 },
+    ]);
+  });
+
+  it('returns elements and background for a valid outline', async () => {
+    const { POST } = await import('@/app/api/generate/scene-content-only/route');
+    const req = new Request('http://localhost/api/generate/scene-content-only', {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json', 'x-model': 'test-model' },
+      body: JSON.stringify({
+        outline: {
+          id: 'o1',
+          type: 'slide',
+          title: 'Slide 1',
+          description: 'Desc',
+          keyPoints: [],
+          order: 1,
+        },
+        stageId: 'stage1',
+      }),
+    });
+    const res = await POST(req as never);
+    const data = await res.json();
+    expect(data.success).toBe(true);
+    expect(data.data.elements).toBeDefined();
+  });
+
+  it('returns 400 when outline is not a slide', async () => {
+    const { POST } = await import('@/app/api/generate/scene-content-only/route');
+    const req = new Request('http://localhost/api/generate/scene-content-only', {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({
+        outline: {
+          id: 'o1',
+          type: 'quiz',
+          title: 'Quiz 1',
+          description: 'Desc',
+          keyPoints: [],
+          order: 1,
+        },
+        stageId: 'stage1',
+      }),
+    });
+    const res = await POST(req as never);
+    expect(res.status).toBe(400);
+  });
+
+  it('returns 400 when outline is missing', async () => {
+    const { POST } = await import('@/app/api/generate/scene-content-only/route');
+    const req = new Request('http://localhost/api/generate/scene-content-only', {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ stageId: 'stage1' }),
+    });
+    const res = await POST(req as never);
+    expect(res.status).toBe(400);
+  });
+
+  it('returns 400 when stageId is missing', async () => {
+    const { POST } = await import('@/app/api/generate/scene-content-only/route');
+    const req = new Request('http://localhost/api/generate/scene-content-only', {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({
+        outline: {
+          id: 'o1',
+          type: 'slide',
+          title: 'Slide 1',
+          description: 'Desc',
+          keyPoints: [],
+          order: 1,
+        },
+      }),
+    });
+    const res = await POST(req as never);
+    expect(res.status).toBe(400);
+  });
+
+  it('returns 404 when stage is not found', async () => {
+    const { getStorageBackend } = await import('@/lib/server/storage');
+    vi.mocked(getStorageBackend).mockReturnValueOnce({
+      loadStage: vi.fn().mockResolvedValue(null),
+      loadOutlines: vi.fn().mockResolvedValue(null),
+    } as never);
+
+    const { POST } = await import('@/app/api/generate/scene-content-only/route');
+    const req = new Request('http://localhost/api/generate/scene-content-only', {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({
+        outline: {
+          id: 'o1',
+          type: 'slide',
+          title: 'Slide 1',
+          description: 'Desc',
+          keyPoints: [],
+          order: 1,
+        },
+        stageId: 'nonexistent',
+      }),
+    });
+    const res = await POST(req as never);
+    expect(res.status).toBe(404);
+  });
+});
diff --git a/tests/hooks/use-scene-regenerator.test.ts b/tests/hooks/use-scene-regenerator.test.ts
new file mode 100644
index 000000000..93de0c605
--- /dev/null
+++ b/tests/hooks/use-scene-regenerator.test.ts
@@ -0,0 +1,110 @@
+import { describe, it, expect } from 'vitest';
+import {
+  outlineToIndication,
+  indicationToOutline,
+  buildMediaGenerations,
+  applyAudioOverride,
+  resolveSkipSlide,
+} from '@/lib/hooks/use-scene-regenerator';
+import type { SpeechAction } from '@/lib/types/action';
+
+describe('outlineToIndication', () => {
+  it('joins description and key points with bullets', () => {
+    const result = outlineToIndication('Intro to React', ['components', 'props']);
+    expect(result).toBe('Intro to React\n• components\n• props');
+  });
+
+  it('returns only description when no key points', () => {
+    expect(outlineToIndication('Just a description', [])).toBe('Just a description');
+  });
+});
+
+describe('indicationToOutline', () => {
+  it('parses bullets as keyPoints and plain lines as description', () => {
+    const result = indicationToOutline('Intro to React\n• components\n• props');
+    expect(result.description).toBe('Intro to React');
+    expect(result.keyPoints).toEqual(['components', 'props']);
+  });
+
+  it('handles indication with no bullets', () => {
+    const result = indicationToOutline('Plain description only');
+    expect(result.description).toBe('Plain description only');
+    expect(result.keyPoints).toEqual([]);
+  });
+});
+
+describe('buildMediaGenerations', () => {
+  it('returns empty array for none', () => {
+    expect(buildMediaGenerations('none')).toEqual([]);
+  });
+
+  it('returns image entry with gen_img_1 elementId', () => {
+    const result = buildMediaGenerations('image', 'A React diagram');
+    expect(result[0].elementId).toBe('gen_img_1');
+    expect(result[0].type).toBe('image');
+    expect(result[0].prompt).toBe('A React diagram');
+  });
+
+  it('returns video entry with gen_vid_1 elementId', () => {
+    const result = buildMediaGenerations('video', 'Animation showing React');
+    expect(result[0].elementId).toBe('gen_vid_1');
+    expect(result[0].type).toBe('video');
+  });
+});
+
+describe('applyAudioOverride', () => {
+  it('maps segments to speech actions by index', () => {
+    const actions = [
+      { type: 'spotlight', id: 's1' },
+      { type: 'speech', text: 'original 1', id: 'sp1' },
+      { type: 'speech', text: 'original 2', id: 'sp2' },
+    ] as Array<{ type: string; text?: string; id: string }>;
+    const result = applyAudioOverride(
+      actions as Parameters<typeof applyAudioOverride>[0],
+      'new segment 1\n\nnew segment 2',
+    );
+    expect((result[1] as SpeechAction).text).toBe('new segment 1');
+    expect((result[2] as SpeechAction).text).toBe('new segment 2');
+  });
+
+  it('keeps AI text when user provides fewer segments than actions', () => {
+    const actions = [
+      { type: 'speech', text: 'original 1', id: 'sp1' },
+      { type: 'speech', text: 'original 2', id: 'sp2' },
+    ] as Parameters<typeof applyAudioOverride>[0];
+    const result = applyAudioOverride(actions, 'only one segment');
+    expect((result[0] as SpeechAction).text).toBe('only one segment');
+    expect((result[1] as SpeechAction).text).toBe('original 2');
+  });
+});
+
+describe('resolveSkipSlide', () => {
+  it('returns false when skipSlide is false regardless of other args', () => {
+    expect(resolveSkipSlide(false, 'image', true)).toBe(false);
+    expect(resolveSkipSlide(false, 'none', false)).toBe(false);
+  });
+
+  it('returns true when skipSlide and mediaType is none', () => {
+    expect(resolveSkipSlide(true, 'none', false)).toBe(true);
+  });
+
+  it('returns true when skipSlide and mediaType is keep', () => {
+    expect(resolveSkipSlide(true, 'keep', false)).toBe(true);
+  });
+
+  it('returns true when skipSlide, new image requested, and existing slot present', () => {
+    expect(resolveSkipSlide(true, 'image', true)).toBe(true);
+  });
+
+  it('returns true when skipSlide, new video requested, and existing slot present', () => {
+    expect(resolveSkipSlide(true, 'video', true)).toBe(true);
+  });
+
+  it('returns false when skipSlide, new image requested, but no existing slot', () => {
+    expect(resolveSkipSlide(true, 'image', false)).toBe(false);
+  });
+
+  it('returns false when skipSlide, new video requested, but no existing slot', () => {
+    expect(resolveSkipSlide(true, 'video', false)).toBe(false);
+  });
+});