diff --git a/widgetlib/textutil.py b/widgetlib/textutil.py
index 09e3f8e..432ff35 100644
--- a/widgetlib/textutil.py
+++ b/widgetlib/textutil.py
@@ -13,7 +13,7 @@ def slugify(title: str) -> str:
     Non-alphanumeric runs collapse to a single hyphen; leading and trailing
     hyphens are stripped.
     """
-    slug = _NON_ALNUM.sub("-", title).strip("-")
+    slug = _NON_ALNUM.sub("-", title).strip("-").lower()
     return slug
 
 
