CSS Preprocessors Docs

CSS Preprocessors Stylus, Sass and {less} Documentation

Sass

the most mature, stable, and powerful professional grade CSS extension language in the world.

CSS Compatible

Sass is completely compatible with all versions of CSS. We take this compatibility seriously, so that you can seamlessly use any available CSS libraries.

Feature Rich

Sass boasts more features and abilities than any other CSS extension language out there. The Sass Core Team has worked endlessly to not only keep up, but stay ahead.

Mature

Sass has been actively supported for over 13 years by its loving Core Team.

Industry Approved

Over and over again, the industry is choosing Sass as the premier CSS extension language.

Large Community

Sass is actively supported and developed by a consortium of several tech companies and hundreds of developers.

Frameworks

There are an endless number of frameworks built with Sass. Compass, Bourbon, and Susy just to name a few.

Stylus

EXPRESSIVE, DYNAMIC, ROBUST CSS

Features

Optional colons

Optional semi-colons

Optional commas

Optional braces

Variables

Interpolation

Mixins

Arithmetic

Type coercion

Dynamic importing

Conditionals

Iteration

Nested selectors

Parent referencing

Variable function calls

Lexical scoping

Built-in functions (over 60)

In-language functions

Optional compression

Optional image inlining

Stylus executable

Robust error reporting

Single-line and multi-line comments

CSS literal for those tricky times

Character escaping

TextMate bundle

and more!

{less}

It's CSS, with just a little more.

Less (which stands for Leaner Style Sheets) is a backwards-compatible language extension for CSS. This is the official documentation for Less, the language and Less.js, the JavaScript tool that converts your Less styles to CSS styles.

Because Less looks just like CSS, learning it is a breeze. Less only makes a few convenient additions to the CSS language, which is one of the reasons it can be learned so quickly.