Better scroll-bars for the TopNav dropdowns

Author: pa4080

src/lib/components/furniture/TopNav.svelte

@@ -362,6 +362,9 @@
     max-height: 80vh;
     overflow-y: auto;
     overflow-x: visible;
+
+    scrollbar-width: thin;
+    scrollbar-color: color-mix(in srgb, var(--color-primary), transparent 10%) transparent;
   }
 
   .dropdown-link {
@@ -514,6 +517,11 @@
     pointer-events: auto;
     white-space: normal;
 
+    max-height: 80vh;
+    overflow-y: auto;
+    scrollbar-width: thin;
+    scrollbar-color: color-mix(in srgb, var(--color-primary), transparent 10%) transparent;
+
     // Smart positioning: try right first, auto-fallback to left
     left: calc(100% + 0.5rem);
     transform-origin: left center;