[fix] mobile navbar errors - closes #596

searx/static/themes/oscar/less/logicodev/navbar.less

         padding: 0 30px;
         margin: 0;
     }
+    z-index: 1;
 }
 
 // Hover color
     color: @light-green;
     background: @black;
 }
+
+.navbar-toggle {
+    margin-top: 0;
+}