diff --git a/src/index.css b/src/index.css
index cec8cbf..f47231e 100644
--- a/src/index.css
+++ b/src/index.css
@@ -12,6 +12,7 @@ code {
 		monospace;
 }
 
+/* for dark mode */
 #root.darkmode img,
 #root.darkmode video,
 #root.darkmode iframe {