diff --git a/flaskr/__init__.py b/flaskr/__init__.py
index f060ca2..e810c25 100644
--- a/flaskr/__init__.py
+++ b/flaskr/__init__.py
@@ -99,7 +99,7 @@ def create_app():
     @app.errorhandler(404)
     def four_oh_four(e):
         theme = request.cookies.get("theme") or "dark"
-        return render_template("404.html", data=data, theme=theme)
+        return render_template("404.html", data=data, theme=theme), 404
 
     def load_page(url):
         if url.endswith(".html"):