diff --git a/src/components/layout/AppShell.tsx b/src/components/layout/AppShell.tsx
index cabf22c..f244c3e 100644
--- a/src/components/layout/AppShell.tsx
+++ b/src/components/layout/AppShell.tsx
@@ -6,6 +6,7 @@ import { AnnouncementBanner } from './AnnouncementBanner';
 import { CommandPalette } from './CommandPalette';
 import { MobileTopBar } from './MobileTopBar';
 import { Sidebar } from './Sidebar';
+import { TopBar } from './TopBar';
 
 /**
  * The persistent application shell, mounted once as a layout route for the
@@ -55,7 +56,7 @@ export function AppShell() {
       <div className="flex min-h-0 flex-1">
       {/* Desktop sidebar */}
       <div className="hidden w-[272px] shrink-0 lg:block">
-        <Sidebar onSearch={openSearch} />
+        <Sidebar />
       </div>
 
       {/* Mobile drawer + backdrop */}
@@ -84,17 +85,11 @@ export function AppShell() {
             drawerOpen ? 'translate-x-0' : '-translate-x-full',
           )}
         >
-          <Sidebar
-            onNavigate={() => setDrawerOpen(false)}
-            onSearch={(seed) => {
-              setDrawerOpen(false);
-              openSearch(seed);
-            }}
-          />
+          <Sidebar onNavigate={() => setDrawerOpen(false)} />
         </div>
       </div>
 
-      {/* Content column: mobile top bar + floating canvas */}
+      {/* Content column: top bar (desktop) / mobile top bar + floating canvas */}
       <div className="flex min-w-0 flex-1 flex-col">
         <MobileTopBar
           ref={menuButtonRef}
@@ -102,6 +97,10 @@ export function AppShell() {
           onMenu={() => setDrawerOpen(true)}
           onSearch={() => openSearch()}
         />
+        {/* Desktop header strip on the exposed outer shell: centered search,
+            bell far right. A shrink-0 sibling of the canvas, so the canvas
+            gives up exactly its height and stays the only scroll region. */}
+        <TopBar onSearch={openSearch} />
         <div className="flex min-h-0 flex-1 flex-col p-2 pt-0 lg:p-3 lg:pl-0 lg:pt-3">
           <main className="min-h-0 flex-1 overflow-y-auto rounded border border-steel/20 bg-canvas">
             <div className="mx-auto max-w-6xl p-4 sm:p-6 lg:p-8">
diff --git a/src/components/layout/CommandPalette.tsx b/src/components/layout/CommandPalette.tsx
index 19976da..10e9db8 100644
--- a/src/components/layout/CommandPalette.tsx
+++ b/src/components/layout/CommandPalette.tsx
@@ -40,10 +40,17 @@ export function CommandPalette({ open, onOpenChange, initialQuery }: CommandPale
   const navigate = useNavigate();
   const [q, setQ] = useState('');
 
-  useHotkeys('mod+k', () => onOpenChange(!open), {
-    enableOnFormTags: true,
-    preventDefault: true,
-  });
+  useHotkeys(
+    'mod+k',
+    () => onOpenChange(!open),
+    {
+      enableOnFormTags: true,
+      preventDefault: true,
+    },
+    // Without deps the callback keeps the first render's `open` (false), so
+    // the shortcut could open the palette but never toggle it closed.
+    [open, onOpenChange],
+  );
 
   // Seed (or clear) the query whenever the palette opens; typing in the
   // sidebar input while open appends through the same channel.
diff --git a/src/components/layout/Sidebar.tsx b/src/components/layout/Sidebar.tsx
index 9be7797..43e89a0 100644
--- a/src/components/layout/Sidebar.tsx
+++ b/src/components/layout/Sidebar.tsx
@@ -1,6 +1,4 @@
-import { Search } from 'lucide-react';
 import { useMe } from '../../features/auth/hooks/useAuth';
-import { NotificationBell } from '../../features/notifications/components/NotificationBell';
 import { Logo } from '../brand/Logo';
 import { SidebarNav } from './SidebarNav';
 import { UserFooter } from './UserFooter';
@@ -9,17 +7,16 @@ import { WorkspaceSwitcher } from './WorkspaceSwitcher';
 interface SidebarProps {
   /** Called after a nav link is activated (closes the mobile drawer). */
   onNavigate?: () => void;
-  /** Opens the command palette, optionally seeded with typed text. */
-  onSearch: (seed?: string) => void;
 }
 
 /**
  * The persistent navigation frame: workspace identity + switcher fixed at the
  * top, an independently scrollable nav list in the middle, and the user
  * footer fixed at the bottom. Rendered both as the desktop rail and inside
- * the mobile drawer.
+ * the mobile drawer. Search and the notification bell live in the shell's
+ * top bar (TopBar on desktop, MobileTopBar below lg), not here.
  */
-export function Sidebar({ onNavigate, onSearch }: SidebarProps) {
+export function Sidebar({ onNavigate }: SidebarProps) {
   const { data: me } = useMe();
   if (!me?.workspace) return null; // guarded by WorkspaceRoute; satisfies types
 
@@ -29,34 +26,6 @@ export function Sidebar({ onNavigate, onSearch }: SidebarProps) {
         <div className="flex items-center gap-1.5">
           <Logo size="sm" withWordmark={false} className="shrink-0 px-1 text-charcoal" />
           <WorkspaceSwitcher workspace={me.workspace} />
-          {/* Operational inbox: right edge of the shell header, before the
-              user's own controls — the "top of the app" position. */}
-          <div className="shrink-0">
-            <NotificationBell />
-          </div>
-        </div>
-        {/* Real search input, centered at the top of the sidebar. Focusing
-            or typing hands off to the floating palette (seeded with the
-            typed text) — one search surface, so the input itself stays
-            empty and the palette owns the query. */}
-        <div className="relative mx-auto mt-3 w-full">
-          <Search
-            size={14}
-            aria-hidden="true"
-            className="pointer-events-none absolute left-2.5 top-1/2 -translate-y-1/2 text-steel"
-          />
-          <input
-            type="search"
-            aria-label="Search workspace"
-            placeholder="Search…"
-            value=""
-            onFocus={() => onSearch()}
-            onChange={(event) => onSearch(event.target.value)}
-            className="w-full rounded border border-steel/20 bg-canvas py-1.5 pl-8 pr-14 text-sm text-charcoal transition-colors placeholder:text-steel hover:border-steel/40 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-primary"
-          />
-          <kbd className="pointer-events-none absolute right-2 top-1/2 -translate-y-1/2 rounded border border-steel/20 bg-surface px-1.5 font-sans text-[11px] text-steel">
-            Ctrl K
-          </kbd>
         </div>
       </div>
       <nav aria-label="Workspace" className="mt-4 min-h-0 flex-1 overflow-y-auto px-3 pb-4">
diff --git a/src/components/layout/TopBar.tsx b/src/components/layout/TopBar.tsx
new file mode 100644
index 0000000..8f338bb
--- /dev/null
+++ b/src/components/layout/TopBar.tsx
@@ -0,0 +1,51 @@
+import { Search } from 'lucide-react';
+import { NotificationBell } from '../../features/notifications/components/NotificationBell';
+
+interface TopBarProps {
+  /** Opens the command palette, optionally seeded with typed text. */
+  onSearch: (seed?: string) => void;
+}
+
+const IS_MAC = /Mac|iPhone|iPad/.test(navigator.platform);
+
+/**
+ * Desktop-only header strip on the outer shell surface, above the floating
+ * content canvas: workspace search centered, the notification bell pinned to
+ * the far right. Below lg these controls live in MobileTopBar instead.
+ */
+export function TopBar({ onSearch }: TopBarProps) {
+  return (
+    <div className="hidden shrink-0 grid-cols-[1fr_minmax(0,28rem)_1fr] items-center gap-2 px-3 pt-3 lg:grid">
+      {/* Left spacer keeps the search truly centered despite the bell. */}
+      <div aria-hidden="true" />
+      {/* Real search input, centered on the shell. Focusing or typing hands
+          off to the floating palette (seeded with the typed text) — one
+          search surface, so the input itself stays empty and the palette
+          owns the query. */}
+      <div className="relative w-full">
+        <Search
+          size={14}
+          aria-hidden="true"
+          className="pointer-events-none absolute left-2.5 top-1/2 -translate-y-1/2 text-steel"
+        />
+        <input
+          type="search"
+          aria-label="Search workspace"
+          placeholder="Search…"
+          value=""
+          onFocus={() => onSearch()}
+          onChange={(event) => onSearch(event.target.value)}
+          className="w-full rounded border border-steel/20 bg-canvas py-1.5 pl-8 pr-14 text-sm text-charcoal transition-colors placeholder:text-steel hover:border-steel/40 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-primary"
+        />
+        <kbd className="pointer-events-none absolute right-2 top-1/2 -translate-y-1/2 rounded border border-steel/20 bg-surface px-1.5 font-sans text-[11px] text-steel">
+          {IS_MAC ? '⌘ K' : 'Ctrl K'}
+        </kbd>
+      </div>
+      {/* Operational inbox at the far right of the outer shell; the bell's
+          popover is portaled and end-aligned, so no extra wiring needed. */}
+      <div className="flex justify-end">
+        <NotificationBell />
+      </div>
+    </div>
+  );
+}