diff --git a/package.json b/package.json
index 7aaa0e5..3eea203 100644
--- a/package.json
+++ b/package.json
@@ -29,7 +29,7 @@
   "dependencies": {
     "cave": "2.0.0",
     "cheerio": "0.22.0",
-    "clean-css": "3.4.20",
+    "clean-css": "3.4.21",
     "css": "2.2.1",
     "detect-indent": "5.0.0",
     "dom-serializer": "0.1.0",