fix: sticky sidebar nav in admin panel

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/app/admin/layout.tsx

@@ -69,7 +69,7 @@ export default function AdminLayout({
 
       {/* Sidebar */}
       <aside
-        className={`fixed inset-y-0 left-0 z-50 flex w-64 flex-col border-r border-white/10 bg-neutral-900 transition-transform lg:static lg:translate-x-0 ${
+        className={`fixed inset-y-0 left-0 z-50 flex w-64 flex-col border-r border-white/10 bg-neutral-900 transition-transform lg:sticky lg:top-0 lg:h-screen lg:translate-x-0 ${
           sidebarOpen ? "translate-x-0" : "-translate-x-full"
         }`}
       >