diff --git a/src/_h5ai/public/css/lib/ext/tree.less b/src/_h5ai/public/css/lib/ext/tree.less
index b73a2338..0b203d31 100644
--- a/src/_h5ai/public/css/lib/ext/tree.less
+++ b/src/_h5ai/public/css/lib/ext/tree.less
@@ -24,7 +24,7 @@
     }
 
     li {
-	clear: left;
+        clear: left;
     }
 
     .active > a {