stylelint : A mighty, modern CSS linter that helps you enforce consistent conventions and avoid errors in your stylesheets.
Sizzy : A tool for developing responsive websites crazy-fast.
Open sourced : https://github.com/kitze/sizzy
Prettier : Prettier is an opinionated code formatter. It enforces a consistent style by parsing your code and re-printing it with its own rules that take the max...
* { CSS:resetr } : To help you find the perfect CSS-reset styles, CSSresetr lets you try all the best CSS Resets on a variety of web pages – even your own.
Autoprefixer : PostCSS plugin to parse CSS and add vendor prefixes to CSS rules using values from Can I Use.
csscss will parse any CSS files you give it and let you know which rulesets have duplicated declarations.
