diff --git a/apps/documenteditor/main/resources/less/toolbar.less b/apps/documenteditor/main/resources/less/toolbar.less
index ec4dc3ecc..1719ba5e4 100644
--- a/apps/documenteditor/main/resources/less/toolbar.less
+++ b/apps/documenteditor/main/resources/less/toolbar.less
@@ -41,7 +41,7 @@
 
 .dropdown-menu.toc-menu {
     @contents-menu-item-height: 72px;
-    --bckgHOffset: 0px;
+    --bckgHOffset: ~"0px";
 
     > li > a.item-contents {
         div {