diff --git a/doc/html/functions_vars.html b/doc/html/functions_vars.html
index cdc5560..cca5603 100644
--- a/doc/html/functions_vars.html
+++ b/doc/html/functions_vars.html
@@ -14,6 +14,7 @@
   $(document).ready(function() { searchBox.OnSelectItem(0); });
 </script>
 <link href="doxygen.css" rel="stylesheet" type="text/css" />
+<link href="doxygen-extra.css" rel="stylesheet" type="text/css"/>
 </head>
 <body>
 <div id="top"><!-- do not remove this div, it is closed by doxygen! -->