improve main nav on mobile

groups/home/LibAnswers-4-js-css.html

@@ -272,6 +272,8 @@ a.no-underline { text-decoration: none; }
 
         #corona-alert { margin: -25px 6px 0px 12px; }
 
+        .mobile-dropdown { max-width: 30%; }
+
         .form-width { width: 210px; }
 
         .zero-margin { margin: 7px auto; }
@@ -397,6 +399,7 @@ a.no-underline { text-decoration: none; }
   right: 0;
 }
 /* End of Yamm */
+
 </style>
 
 <!-- scripts to make the Book a Study Room widget run -->