diff --git a/site/layouts/partials/subpage_navbar.html b/site/layouts/partials/subpage_navbar.html
index f1bc01e..0403ec8 100644
--- a/site/layouts/partials/subpage_navbar.html
+++ b/site/layouts/partials/subpage_navbar.html
@@ -1,5 +1,5 @@
 {{ "<!-- NAVIGATION ON PAGES -->" | safeHTML }}
-<nav id="mainNav" class="navbar navbar-default navbar-fixed-top">
+<nav id="mainNav" class="navbar navbar-default navbar-fixed-top affix">
     <div class="container-fluid">
         {{ "<!-- Brand and toggle get grouped for better mobile display -->" | safeHTML }}
         <div class="navbar-header">