diff --git a/package.json b/package.json
index 40427d6..d241e40 100644
--- a/package.json
+++ b/package.json
@@ -3,7 +3,7 @@
   "version": "0.2.0",
   "description": "A sample package.json",
   "dependencies": {
-    "@primer/css": "17.0.1"
+    "@primer/css": "21.5.1"
   },
   "license": "MIT"
 }