diff --git a/css/html_instruct_style.css b/css/html_instruct_style.css
index 6956e920..71b03d43 100644
--- a/css/html_instruct_style.css
+++ b/css/html_instruct_style.css
@@ -74,7 +74,7 @@
 }
 
 .dark .chat .assistant-message {
-    background-color: #374151;
+    background-color: #3741519e;
     border: 1px solid #4b5563;
 }