diff --git a/memento-note/components/sidebar.tsx b/memento-note/components/sidebar.tsx
index 824cc0d..21838a1 100644
--- a/memento-note/components/sidebar.tsx
+++ b/memento-note/components/sidebar.tsx
@@ -547,6 +547,8 @@ export function Sidebar({ className, user }: { className?: string; user?: any })
       const next = new Set(prev)
       if (next.has(id)) {
         next.delete(id)
+        // Also collapse the notebook when unpinning
+        setExpandedIds(e => { const ne = new Set(e); ne.delete(id); return ne })
       } else {
         next.add(id)
         // Ensure it's also expanded when pinned