diff --git a/frontend/app/element/markdown.less b/frontend/app/element/markdown.less
index b77ffc079..3a1f15daa 100644
--- a/frontend/app/element/markdown.less
+++ b/frontend/app/element/markdown.less
@@ -75,6 +75,7 @@
                 word-wrap: break-word;
                 overflow: auto;
                 overflow: hidden;
+                background-color: transparent;
             }
 
             .codeblock-actions {