### Adding or Updating Examples
Migrate the basic-css example from page router to app router. If it
needs further updates, Please let me know
Happy to contribute
---------
Co-authored-by: Steven <steven@ceriously.com>
Converted basic CSS example over to TypeScript to match the Contribution guidelines.
## Documentation / Examples
- [ ] Make sure the linting passes by running `pnpm lint`
- [ ] The examples guidelines are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing.md#adding-examples)