diff --git a/khata/web/static/editor.js b/khata/web/static/editor.js
index 4ffb858..862e2b0 100644
--- a/khata/web/static/editor.js
+++ b/khata/web/static/editor.js
@@ -2,12 +2,15 @@
 (function () {
   "use strict";
 
-  function uploadImage(uploadUrl, file, onSuccess, onError) {
+  function upload(uploadUrl, file, onSuccess, onError) {
     const fd = new FormData();
     fd.append("file", file);
     fetch(uploadUrl, { method: "POST", body: fd })
       .then(async (r) => {
-        if (!r.ok) throw new Error(`Upload failed: ${r.status}`);
+        if (!r.ok) {
+          const txt = await r.text().catch(() => "");
+          throw new Error(`upload ${r.status}: ${txt.slice(0, 120)}`);
+        }
         return r.json();
       })
       .then((j) => onSuccess((j && j.url) || (j && j.data && j.data.filePath)))
@@ -19,30 +22,42 @@
     textarea.dataset.khataMounted = "1";
 
     const uploadUrl = textarea.dataset.upload;
+    const hasUpload = !!uploadUrl;
 
     const easy = new EasyMDE({
       element: textarea,
       autoDownloadFontAwesome: false,
       spellChecker: false,
       status: ["lines", "words"],
-      minHeight: "160px",
-      uploadImage: !!uploadUrl,
-      imageUploadFunction: uploadUrl
-        ? (file, onSuccess, onError) => uploadImage(uploadUrl, file, onSuccess, onError)
-        : undefined,
+      minHeight: "200px",
+      // Enables paste + drag-drop + the 'upload-image' toolbar button.
+      uploadImage: hasUpload,
+      imageAccept: "image/png, image/jpeg, image/webp, image/gif",
+      imageMaxSize: 10 * 1024 * 1024,
       imagePathAbsolute: true,
+      imageUploadFunction: hasUpload
+        ? (file, onSuccess, onError) => upload(uploadUrl, file, onSuccess, onError)
+        : undefined,
+      // Toolbar items must use 'upload-image' (not 'image') to trigger the
+      // file-picker + imageUploadFunction flow. 'image' only inserts a stub
+      // `![alt](url)` line, which was the source of "can't upload" confusion.
       toolbar: [
         "bold", "italic", "heading", "|",
         "quote", "unordered-list", "ordered-list", "|",
-        "link", "image", "code", "|",
-        "preview", "side-by-side", "|",
+        "link", hasUpload ? "upload-image" : "image", "code", "|",
+        {
+          // Custom preview-toggle button with an explicit title so users can
+          // see how to come *back* from preview mode.
+          name: "preview",
+          action: EasyMDE.togglePreview,
+          className: "fa fa-eye no-disable",
+          title: "Toggle preview (click again to go back)",
+          noDisable: true,
+        },
+        "side-by-side", "fullscreen", "|",
         "guide",
       ],
-      previewRender: (text) => {
-        // Use marked if available — otherwise EasyMDE's default. marked ships
-        // inside EasyMDE.
-        return easy.markdown(text);
-      },
+      previewRender: (text) => easy.markdown(text),
     });
 
     // Keep the native textarea's value in sync so HTMX form submission works.
diff --git a/khata/web/static/style.css b/khata/web/static/style.css
index 089913b..d192d7d 100644
--- a/khata/web/static/style.css
+++ b/khata/web/static/style.css
@@ -436,9 +436,16 @@ h2 {
 }
 .note-block .editor-toolbar button.active,
 .note-block .editor-toolbar button.fa.active {
-  background: var(--surface);
-  color: var(--accent) !important;
-  border-color: var(--border);
+  background: var(--accent);
+  color: var(--accent-ink) !important;
+  border-color: var(--accent);
+}
+/* Preview/fullscreen dim other buttons. Keep them readable so the user can
+   still see the preview button to click it again and return. */
+.note-block .editor-toolbar.disabled-for-preview button:not(.no-disable),
+.note-block .editor-toolbar button[disabled] {
+  opacity: 0.35;
+  cursor: not-allowed;
 }
 .note-block .editor-toolbar i.separator { border-color: var(--border); }