diff --git a/web/test/runner.less b/web/test/runner.less
index f197cc6c..355d5422 100644
--- a/web/test/runner.less
+++ b/web/test/runner.less
@@ -11,6 +11,12 @@ body {
   background-color: #233930;
 }
 
+#test-list {
+  width: 100%;
+  height: ~"calc(40% - 22px)";
+  overflow-y: scroll;
+}
+
 #sandbox iframe {
   border: 0;
   width: 100%;