diff --git a/agaric/css/agaric.css b/agaric/css/agaric.css
index 683c28a..c3ba6f5 100644
--- a/agaric/css/agaric.css
+++ b/agaric/css/agaric.css
@@ -10446,7 +10446,8 @@ a.navbar-link:hover {
   position: absolute;
   top: 250px;
   left: 0.75rem;
-  z-index: 1; }
+  z-index: 1;
+  background: rgba(255, 255, 255, 0.75); }
 
 a.card {
   display: block; }