diff --git a/package-lock.json b/package-lock.json
index 1bbb689..84af6db 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -14,7 +14,7 @@
         "@types/chai": "^5.2.3",
         "@types/mocha": "^10.0.10",
         "@types/node": "22",
-        "@webref/css": "^8.5.0",
+        "@webref/css": "^8.5.1",
         "chai": "^6.2.2",
         "dedent-js": "^1.0.1",
         "eslint": "^10.1.0",
@@ -533,9 +533,9 @@
       }
     },
     "node_modules/@webref/css": {
-      "version": "8.5.0",
-      "resolved": "https://registry.npmjs.org/@webref/css/-/css-8.5.0.tgz",
-      "integrity": "sha512-VkjXMzgzJFiGCrfDqt30QbI4sXn70Cn5YM3DaAWiv5SpC4MN5Fg8JkA5LZzOWzj/anRJD5X4iFNI1JY9zyXG6A==",
+      "version": "8.5.1",
+      "resolved": "https://registry.npmjs.org/@webref/css/-/css-8.5.1.tgz",
+      "integrity": "sha512-i+LdAd8oXjbquyQLKGcCbUiR9Zr+eVpfzihLk2FpxjLtJKDbxZQoUbiGZnh41jI7KJcTBc/SiNCx43bbGqoQIQ==",
       "dev": true,
       "license": "MIT",
       "peerDependencies": {
diff --git a/package.json b/package.json
index 4d0571b..ef71e0e 100644
--- a/package.json
+++ b/package.json
@@ -20,7 +20,7 @@
     "@types/chai": "^5.2.3",
     "@types/mocha": "^10.0.10",
     "@types/node": "22",
-    "@webref/css": "^8.5.0",
+    "@webref/css": "^8.5.1",
     "chai": "^6.2.2",
     "dedent-js": "^1.0.1",
     "eslint": "^10.1.0",