fix: Sidebar positioning - remove inset-y-0 conflict

- Fixed sidebar to not use inset-y-0 (was overriding top offset)
- Mobile: fixed positioning with sidebarTopClass
- Desktop: lg:sticky for proper sticky behavior

admin-spa/src/routes/Help/index.tsx

@@ -96,14 +96,16 @@ export default function Help() {
                 {sidebarOpen ? <X className="w-5 h-5" /> : <Menu className="w-5 h-5" />}
             </Button>
 
-            {/* Sidebar - sticky, positioned below header */}
+            {/* Sidebar - sticky on desktop, fixed on mobile */}
             <aside
                 className={cn(
-                    "w-72 border-r bg-muted/30 flex-shrink-0",
-                    "fixed lg:sticky inset-y-0 left-0 z-40",
+                    "w-72 border-r bg-muted/30 flex-shrink-0 overflow-y-auto",
+                    // Mobile: fixed position covering from below header
+                    "fixed left-0 z-40",
                     sidebarTopClass,
                     sidebarHeightClass,
-                    "lg:block overflow-y-auto",
+                    // Desktop: sticky instead of fixed
+                    "lg:sticky",
                     sidebarOpen ? "block" : "hidden lg:block"
                 )}
             >