diff --git a/src/app/chain/page.tsx b/src/app/chain/page.tsx
index fb93ddce..996ae812 100644
--- a/src/app/chain/page.tsx
+++ b/src/app/chain/page.tsx
@@ -13,6 +13,7 @@ import { useChainPlot } from "../../hooks/useChainPlot";
 import type { PublishState } from "../../hooks/usePublish";
 import Link from "next/link";
 import { ConnectWallet } from "../../components/ConnectWallet";
+import { Select } from "../../components/Select";
 
 const STATE_LABELS: Record<PublishState, string> = {
   idle: "",
@@ -120,22 +121,16 @@ export default function ChainPlotPage() {
               </Link>
             </p>
           ) : (
-            <select
-              value={storylineId ?? ""}
-              onChange={(e) =>
-                setStorylineId(e.target.value ? Number(e.target.value) : null)
-              }
+            <Select
+              value={storylineId != null ? String(storylineId) : ""}
+              onChange={(v) => setStorylineId(v ? Number(v) : null)}
               disabled={busy}
-              className="border-border bg-surface text-foreground w-full rounded border px-3 pr-10 py-2 text-sm focus:border-accent focus:outline-none disabled:opacity-50"
-            >
-              <option value="">Select a storyline</option>
-              {storylines.map((s) => (
-                <option key={s.id} value={s.storyline_id}>
-                  {s.title} ({s.plot_count}{" "}
-                  {s.plot_count === 1 ? "plot" : "plots"})
-                </option>
-              ))}
-            </select>
+              placeholder="Select a storyline"
+              options={storylines.map((s) => ({
+                value: String(s.storyline_id),
+                label: `${s.title} (${s.plot_count} ${s.plot_count === 1 ? "plot" : "plots"})`,
+              }))}
+            />
           )}
         </div>
 
diff --git a/src/app/globals.css b/src/app/globals.css
index 85d98297..bf7a84b0 100644
--- a/src/app/globals.css
+++ b/src/app/globals.css
@@ -46,12 +46,3 @@ select {
   padding-right: 2.5rem;
 }
 
-select option {
-  background: var(--bg-surface);
-  color: var(--text);
-}
-
-select option:checked {
-  background: var(--accent);
-  color: var(--bg);
-}
diff --git a/src/app/register-agent/page.tsx b/src/app/register-agent/page.tsx
index 98e8b12e..6b3ac029 100644
--- a/src/app/register-agent/page.tsx
+++ b/src/app/register-agent/page.tsx
@@ -8,6 +8,7 @@ import { publicClient } from "../../../lib/rpc";
 import { erc8004Abi } from "../../../lib/contracts/erc8004";
 import { ERC8004_REGISTRY, BASE_CHAIN_ID, EXPLORER_URL } from "../../../lib/contracts/constants";
 import { ConnectWallet } from "../../components/ConnectWallet";
+import { Select } from "../../components/Select";
 
 // ---------------------------------------------------------------------------
 // Constants
@@ -357,18 +358,12 @@ export default function RegisterAgentPage() {
             <label className="text-foreground mb-2 block text-sm">
               Primary Genre
             </label>
-            <select
+            <Select
               value={genre}
-              onChange={(e) => setGenre(e.target.value)}
-              className="border-border bg-surface text-foreground w-full rounded border px-3 pr-10 py-2 text-sm focus:border-accent focus:outline-none"
-            >
-              <option value="">Select genre...</option>
-              {GENRES.map((g) => (
-                <option key={g} value={g}>
-                  {g}
-                </option>
-              ))}
-            </select>
+              onChange={setGenre}
+              placeholder="Select genre..."
+              options={GENRES.map((g) => ({ value: g, label: g }))}
+            />
           </div>
 
           {/* LLM Model */}
@@ -376,18 +371,12 @@ export default function RegisterAgentPage() {
             <label className="text-foreground mb-2 block text-sm">
               LLM Model
             </label>
-            <select
+            <Select
               value={llmModel}
-              onChange={(e) => setLlmModel(e.target.value)}
-              className="border-border bg-surface text-foreground w-full rounded border px-3 pr-10 py-2 text-sm focus:border-accent focus:outline-none"
-            >
-              <option value="">Select model...</option>
-              {LLM_MODELS.map((m) => (
-                <option key={m} value={m}>
-                  {m}
-                </option>
-              ))}
-            </select>
+              onChange={setLlmModel}
+              placeholder="Select model..."
+              options={LLM_MODELS.map((m) => ({ value: m, label: m }))}
+            />
           </div>
 
           {/* Metadata preview */}
diff --git a/src/components/Select.tsx b/src/components/Select.tsx
new file mode 100644
index 00000000..fcb457f0
--- /dev/null
+++ b/src/components/Select.tsx
@@ -0,0 +1,157 @@
+"use client";
+
+import { useState, useRef, useEffect, useCallback } from "react";
+
+export interface SelectOption {
+  value: string;
+  label: string;
+}
+
+interface SelectProps {
+  value: string;
+  onChange: (value: string) => void;
+  options: SelectOption[];
+  placeholder?: string;
+  disabled?: boolean;
+  className?: string;
+}
+
+export function Select({
+  value,
+  onChange,
+  options,
+  placeholder = "Select...",
+  disabled = false,
+  className = "",
+}: SelectProps) {
+  const [open, setOpen] = useState(false);
+  const [focusIndex, setFocusIndex] = useState(-1);
+  const containerRef = useRef<HTMLDivElement>(null);
+  const listRef = useRef<HTMLUListElement>(null);
+
+  const allOptions = placeholder
+    ? [{ value: "", label: placeholder }, ...options]
+    : options;
+
+  const selectedLabel =
+    options.find((o) => o.value === value)?.label ?? placeholder;
+
+  // Close on click outside
+  useEffect(() => {
+    if (!open) return;
+    function handleClick(e: MouseEvent) {
+      if (containerRef.current && !containerRef.current.contains(e.target as Node)) {
+        setOpen(false);
+      }
+    }
+    document.addEventListener("mousedown", handleClick);
+    return () => document.removeEventListener("mousedown", handleClick);
+  }, [open]);
+
+  // Scroll focused option into view
+  useEffect(() => {
+    if (!open || focusIndex < 0 || !listRef.current) return;
+    const el = listRef.current.children[focusIndex] as HTMLElement | undefined;
+    el?.scrollIntoView({ block: "nearest" });
+  }, [open, focusIndex]);
+
+  const handleKeyDown = useCallback(
+    (e: React.KeyboardEvent) => {
+      if (disabled) return;
+
+      if (!open) {
+        if (e.key === "Enter" || e.key === " " || e.key === "ArrowDown") {
+          e.preventDefault();
+          setOpen(true);
+          setFocusIndex(0);
+        }
+        return;
+      }
+
+      switch (e.key) {
+        case "ArrowDown":
+          e.preventDefault();
+          setFocusIndex((i) => Math.min(i + 1, allOptions.length - 1));
+          break;
+        case "ArrowUp":
+          e.preventDefault();
+          setFocusIndex((i) => Math.max(i - 1, 0));
+          break;
+        case "Enter":
+          e.preventDefault();
+          if (focusIndex >= 0 && focusIndex < allOptions.length) {
+            onChange(allOptions[focusIndex].value);
+            setOpen(false);
+          }
+          break;
+        case "Escape":
+          e.preventDefault();
+          setOpen(false);
+          break;
+      }
+    },
+    [disabled, open, allOptions, focusIndex, onChange],
+  );
+
+  return (
+    <div ref={containerRef} className={`relative ${className}`}>
+      <button
+        type="button"
+        onClick={() => !disabled && setOpen((o) => !o)}
+        onKeyDown={handleKeyDown}
+        disabled={disabled}
+        aria-haspopup="listbox"
+        aria-expanded={open}
+        className="border-border bg-surface text-foreground w-full rounded border px-3 pr-10 py-2 text-left text-sm focus:border-accent focus:outline-none disabled:opacity-50"
+      >
+        <span className={value ? "" : "text-muted"}>{selectedLabel}</span>
+        <svg
+          className="text-muted pointer-events-none absolute right-3 top-1/2 -translate-y-1/2"
+          width="12"
+          height="12"
+          viewBox="0 0 24 24"
+          fill="none"
+          stroke="currentColor"
+          strokeWidth="2"
+          strokeLinecap="round"
+          strokeLinejoin="round"
+        >
+          <polyline points="6 9 12 15 18 9" />
+        </svg>
+      </button>
+
+      {open && (
+        <ul
+          ref={listRef}
+          role="listbox"
+          onKeyDown={handleKeyDown}
+          className="border-border bg-surface absolute z-50 mt-1 max-h-60 w-full overflow-auto rounded border py-1 shadow-lg"
+        >
+          {allOptions.map((opt, i) => (
+            <li
+              key={opt.value === "" ? "__placeholder__" : opt.value}
+              role="option"
+              aria-selected={opt.value === value}
+              onMouseEnter={() => setFocusIndex(i)}
+              onClick={() => {
+                onChange(opt.value);
+                setOpen(false);
+              }}
+              className={`cursor-pointer px-3 py-2 text-sm ${
+                opt.value === value
+                  ? "bg-accent text-background"
+                  : i === focusIndex
+                    ? "bg-border/50 text-foreground"
+                    : opt.value === ""
+                      ? "text-muted hover:bg-border/30"
+                      : "text-foreground hover:bg-border/30"
+              }`}
+            >
+              {opt.label}
+            </li>
+          ))}
+        </ul>
+      )}
+    </div>
+  );
+}