diff --git a/public/css/main.less b/public/css/main.less
index dc43261bfa..5187ba93f6 100644
--- a/public/css/main.less
+++ b/public/css/main.less
@@ -1092,6 +1092,7 @@ hr {
   .iframe-scroll {
     position: fixed !important;
     margin-top: 75px;
+    z-index: 9999;
   }
 }
 @media only screen and (max-width: 992px) {