fix(menu): jitter when closing menu

It's caused by flexbox gap property, which can't animate

assets/scss/partials/sidebar.scss

@@ -11,7 +11,6 @@
     flex-direction: column;
     flex-shrink: 0;
     align-self: stretch;
-    gap: var(--sidebar-element-separation);
     max-width: none;
     width: 100%;
     position: relative;
@@ -65,6 +64,11 @@
             }
         }
     }
+
+    .social-menu,
+    .menu {
+        margin-top: var(--sidebar-element-separation);
+    }
 }
 
 .right-sidebar {