diff --git a/src/styles/post.scss b/src/styles/post.scss
index 35bc597..05d9939 100644
--- a/src/styles/post.scss
+++ b/src/styles/post.scss
@@ -104,6 +104,7 @@
         position: sticky;
         top: 0;
         background-color: var(--background-color);
+        z-index: 2;
       }
 
       &[open] summary {