diff --git a/module/doc/ui/view.html.php b/module/doc/ui/view.html.php
index 66b2dc1a6a..1e485bb81c 100644
--- a/module/doc/ui/view.html.php
+++ b/module/doc/ui/view.html.php
@@ -253,6 +253,7 @@ $treeDom = isset($outlineTree) ? div
     setID('contentTree'),
     tree
     (
+        set::className('pl-4'),
         set::items($outlineTree),
         set::defaultNestedShow(true)
     )