diff --git src/wp-admin/css/admin-menu.css src/wp-admin/css/admin-menu.css
index b8bf6b2..49c2af0 100644
--- src/wp-admin/css/admin-menu.css
+++ src/wp-admin/css/admin-menu.css
@@ -7,10 +7,10 @@
 }
 
 #adminmenuback {
-	position: absolute;
+	position: fixed;
 	top: 0;
 	bottom: 0;
-	z-index: -1;
+	z-index: 9980; /* just beneath #adminmenuwrap */
 }
 
 #adminmenu {