improve world tree on mobile #101

client/src/css/world_tree.css

@@ -49,7 +49,6 @@ svg .disabled {
 }
 
 .world-selection-menu {
-  position: absolute;
   right: 1em;
   top: 1em;
   /* margin: 1em; */
@@ -60,6 +59,10 @@ svg .disabled {
   filter: drop-shadow(4px 4px 5px rgba(0,0,0,0.5));
 }
 
+.world-selection-menu.desktop {
+  position: absolute;
+}
+
 .world-selection-menu .btn, .welcome .btn {
   min-width: 5em;
   text-align: center;