Bump @webref/css from 6.23.15 to 8.0.0

Bumps [@webref/css](https://github.com/w3c/webref) from 6.23.15 to 8.0.0.
- [Commits](https://github.com/w3c/webref/compare/@webref/css6@6.23.15...@webref/css@8.0.0)

---
updated-dependencies:
- dependency-name: "@webref/css"
  dependency-version: 8.0.0
  dependency-type: direct:development
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

package-lock.json

@@ -47,7 +47,7 @@
     "@typescript-eslint/eslint-plugin": "^8",
     "@typescript-eslint/parser": "^8",
     "@typescript/native-preview": "^7.0.0-dev.20251029.1",
-    "@webref/css": "^6.23.7",
+    "@webref/css": "^8.0.0",
     "@webref/elements": "^2.5.0",
     "@webref/events": "^1.18.6",
     "@webref/idl": "^3.66.2",