diff --git a/static/tree-view.css b/static/tree-view.css
index 18751fad1..5f148dfac 100644
--- a/static/tree-view.css
+++ b/static/tree-view.css
@@ -80,6 +80,7 @@
   color: white;
   border: 2px solid #222;
   -webkit-box-shadow: 0 0 3px 3px rgba(0, 0, 0, .5);
+  z-index: 99;
 }
 
 .tree-view .directory .header .name,