diff --git a/app/views/fluentd/settings/show.html.haml b/app/views/fluentd/settings/show.html.haml
index 18f5717..1adf293 100644
--- a/app/views/fluentd/settings/show.html.haml
+++ b/app/views/fluentd/settings/show.html.haml
@@ -4,8 +4,8 @@
     = t("terms.edit")
 
 .row
-  .col-xl-12
-    %pre
+  .card.col-xl-12
+    %pre.card-body
       = preserve do
         = @config