Merge pull request #28086 from overleaf/ac-incread-mobile-nav-z-index

[web] Increase the z-index of the navbar on small screens

GitOrigin-RevId: 528260507937d0a1691eb41ebc69cb4926ac89c4

services/web/frontend/stylesheets/components/navbar.scss

@@ -147,7 +147,7 @@
 
     background-color: var(--navbar-bg);
     margin: 0 calc(-1 * var(--navbar-padding-h));
-    z-index: 1;
+    z-index: 10;
 
     .navbar-nav {
       > li {