diff --git a/docs/assets/css/bootstrap.css b/docs/assets/css/bootstrap.css
index c89cd7af6f..ebfc45fdd4 100644
--- a/docs/assets/css/bootstrap.css
+++ b/docs/assets/css/bootstrap.css
@@ -2870,6 +2870,8 @@ button.close {
   position: absolute;
   top: 10px;
   right: 10px;
+  width: 48px;
+  height: 32px;
   padding: 8px 12px;
   background-color: transparent;
   border: 1px solid #ddd;
diff --git a/less/navbar.less b/less/navbar.less
index 6efac5f4e7..c87c8e68c3 100644
--- a/less/navbar.less
+++ b/less/navbar.less
@@ -119,6 +119,8 @@
   position: absolute;
   top: 10px;
   right: 10px;
+  width: 48px;
+  height: 32px;
   padding: 8px 12px;
   background-color: transparent;
   border: 1px solid #ddd;