diff --git a/common/app/routes/Challenges/challenges.less b/common/app/routes/Challenges/challenges.less
index 78c2dbc6d2..ea71e73058 100644
--- a/common/app/routes/Challenges/challenges.less
+++ b/common/app/routes/Challenges/challenges.less
@@ -124,6 +124,9 @@
   .refresh-icon {
     color: @icon-light-gray;
   }
+  .@{ns}-preview {
+    background-color: #FCFCFC;
+  }
 }
 
 .@{ns}-test-output {