diff --git a/src/_h5ai/client/css/inc/sidebar.less b/src/_h5ai/client/css/inc/sidebar.less
index ce4c28aa..48418a83 100644
--- a/src/_h5ai/client/css/inc/sidebar.less
+++ b/src/_h5ai/client/css/inc/sidebar.less
@@ -14,6 +14,7 @@
     .block {
         display: block;
         margin: 0 0 24px 0;
+        width: 168px;
 
         h1 {
             font-size: 1em;