diff --git a/index.html b/index.html
index ecb6572..b51533b 100644
--- a/index.html
+++ b/index.html
@@ -342,6 +342,8 @@
             ul {
                 float: left;
                 clear: both;
+                height: 1em; /* fallback */
+                height: 10vmin;
                 list-style-type: none;
                 padding: 0;
                 margin: 0;