diff --git a/src/components/nav-bar/nav-bar.less b/src/components/nav-bar/nav-bar.less
index 1940e8f05a..57153f7c5f 100644
--- a/src/components/nav-bar/nav-bar.less
+++ b/src/components/nav-bar/nav-bar.less
@@ -1,12 +1,10 @@
 @class-prefix-nav-bar: ~'adm-nav-bar';
 
 .@{class-prefix-nav-bar} {
-  --height: 45px;
-  --border-bottom: none;
   display: flex;
   align-items: center;
-  height: var(--height);
-  border-bottom: var(--border-bottom);
+  height: var(--height, 45px);
+  border-bottom: var(--border-bottom, none);
   padding: 0 12px;
   white-space: nowrap;