A mighty, modern linter that helps you avoid errors and enforce conventions in your styles.

Features

It's mighty because it:

has over 160 built-in rules to catch errors, apply limits and enforce stylistic conventions
understands the latest CSS syntax including custom properties and level 4 selectors
extracts embedded styles from HTML, markdown and CSS-in-JS object & template literals
parses CSS-like syntaxes like SCSS, Sass, Less and SugarSS
supports plugins so you can create your own rules or make use of plugins written by the community
automatically fixes some violations (experimental feature)
is well tested with over 10000 unit tests
supports shareable configs that you can extend or create your own of
is unopinionated so you can tailor the linter to your exact needs
has a growing community and is used by Facebook, GitHub and WordPress