We all experience how CSS preprocessors like SASS or LESS ease working on projects with complex styles.
Roole is another alternative that is inspired from SASS, LESS + Stylus and only requires JavaScript to work.
It has vendor-prefixing built-in so there is no need to use them, supports variables + conditional logic and allows us to define the format we want to code CSS.
Roole can work both on the client or server-side (nodejs) and it is documented well.
Download: https://github.com/curvedmark/roole
