diff --git a/layouts/shortcodes/expand.html b/layouts/shortcodes/expand.html
deleted file mode 100644
index f254944..0000000
--- a/layouts/shortcodes/expand.html
+++ /dev/null
@@ -1,13 +0,0 @@
-{{ warnf "Expand shortcode is deprecated. Use 'details' instead." }}
-<div class="book-expand">
-  <label>
-    <div class="book-expand-head flex justify-between">
-      <span>{{ default (i18n "Expand") (.Get 0) }}</span>
-      <span>{{ default "↕" (.Get 1) }}</span>
-    </div>
-    <input type="checkbox" class="hidden" />
-    <div class="book-expand-content markdown-inner">
-      {{ .Inner | markdownify }}
-    </div>
-  </label>
-</div>