stylelint
A linter that helps you avoid errors and enforce conventions
... well tested with over 15000 unit tests. Supports shareable configs that you can extend or create. It is unopinionated so that you can customize it to your exact needs. stylelint has a growing community and is used by Facebook, GitHub and WordPress. You can configure the built-in stylistic rules to allow both multi-line and single-line rules. The choice of when to use each belongs to the user.