diff --git a/src/flask_imp/config/imp_blueprint_config.py b/src/flask_imp/config/imp_blueprint_config.py
index 12e3213d..61592b60 100644
--- a/src/flask_imp/config/imp_blueprint_config.py
+++ b/src/flask_imp/config/imp_blueprint_config.py
@@ -37,9 +37,9 @@ def __init__(
         url_prefix: t.Optional[str] = None,
         subdomain: t.Optional[str] = None,
         url_defaults: t.Optional[t.Dict[str, t.Any]] = None,
-        static_folder: str = "static",
-        template_folder: str = "templates",
-        static_url_path: str = "/static",
+        static_folder: t.Optional[str] = None,
+        template_folder: t.Optional[str] = None,
+        static_url_path: t.Optional[str] = None,
         root_path: t.Optional[str] = None,
         cli_group: t.Optional[str] = None,
         init_session: t.Optional[t.Dict[str, t.Any]] = None,