diff --git a/test/styles.less b/test/styles.less
index f260daf1..c197040f 100644
--- a/test/styles.less
+++ b/test/styles.less
@@ -42,7 +42,8 @@
     bottom: 0;
     background: #fff;
     z-index: 10000;
-    overflow: auto;
+    overflow-x: auto;
+    overflow-y: scroll;
 }
 
 #mocha {