diff --git a/templates/partials/header.html b/templates/partials/header.html
index 2cdc40e..2ee18a4 100644
--- a/templates/partials/header.html
+++ b/templates/partials/header.html
@@ -28,7 +28,7 @@
 
       // mobile menu
       const btnMenu = document.querySelector(".btn-menu");
-      btnMenu.addEventListener("click", () => {
+      btnMenu?.addEventListener("click", () => {
         htmlClass.toggle("open");
       });