diff --git a/templates/modular.html.twig b/templates/modular.html.twig
index 7decd7a..6fb2d71 100644
--- a/templates/modular.html.twig
+++ b/templates/modular.html.twig
@@ -25,7 +25,12 @@
     {% endif %}
 {% endblock %}
 
-{% block body_classes %}{{ parent() }} fixed-nav{% endblock %}
+{% block body_classes %}
+    {{ parent() }}
+    {% if show_onpage_menu %}
+        fixed-nav
+    {% endif %}
+{% endblock %}
 
 {% block header_navigation %}
     {% if show_onpage_menu %}