diff --git a/styles/css/cover.css b/styles/css/cover.css
index 6fd120aa..4ad1456f 100644
--- a/styles/css/cover.css
+++ b/styles/css/cover.css
@@ -47,6 +47,7 @@ body {
   display: table-cell;
   vertical-align: top;
   padding-top: 1em;
+  height: 100%; /* For Firefox */
 }
 .cover-container {
   margin-right: auto;