close gap, use border-box for box-sizing

src/components/navigation/www/navigation.scss

@@ -186,9 +186,11 @@
         }
 
         .dropdown {
+            top: 50px;
             padding: 0;
             padding-top: 5px;
             width: 100%;
+            box-sizing: border-box;
         }
     }
 }