diff --git a/scss/topic.scss b/scss/topic.scss
index 77f9bba..ee2b288 100644
--- a/scss/topic.scss
+++ b/scss/topic.scss
@@ -47,7 +47,7 @@
 }
 
 #topic-title {
-  z-index: 999;
+  z-index: z("composer", "content") - 1;
   padding: var(--spacing-block-l) var(--spacing-inline-xl);
   position: sticky;
   margin-bottom: 0;