diff --git a/theme/book.js b/theme/book.js
index b9531745b1a..3c46f6af926 100644
--- a/theme/book.js
+++ b/theme/book.js
@@ -721,4 +721,4 @@ function playground_text(playground, hidden = true) {
         updateBorder();
         document.addEventListener('scroll', updateBorder, { passive: true });
     })();
-})();
\ No newline at end of file
+})();