fix dropdown fade animation by specifying transition property

The .fade rule only set transition-duration without specifying
transition-property, so opacity changes were instant. Also fixes
a typo where the webkit duration was 5s instead of 0.5s.

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

groups/home/bootstrap5/home1.css

@@ -97,8 +97,8 @@
     opacity: 1;
   }
   .fade {
-    -webkit-transition-duration: 5s; /* Safari */
-    transition-duration: 0.5s;
+    transition: opacity 0.5s ease;
+    -webkit-transition: opacity 0.5s ease; /* Safari */
   }
   /* Show dropdown on hover AND keyboard focus (WCAG 2.1.1) */
   .dropdown:hover .dropdown-menu,