Sass makes CSS fun again. Sass is an extension of CSS, adding nested rules, variables, mixins, selector inheritance, and more. It's translated to well-formatted, standard CSS using the command line tool or a plugin for your build system.

$font-stack: Helvetica, sans-serif;
$primary-color: #333;

body {
  font: 100% $font-stack;
  color: $primary-color;
}

@mixin border-radius($radius) {
  -webkit-border-radius: $radius;
     -moz-border-radius: $radius;
      -ms-border-radius: $radius;
          border-radius: $radius;
}

nav {
  ul {
    margin: 0;
    padding: 0;
    list-style: none;
  }

  li { @include border-radius(10px); }

  a {
    display: block;
    padding: 6px 12px;
    text-decoration: none;
  }
}

You can install Sass on Windows, Mac, or Linux by downloading the package for your operating system from GitHub and adding it to your PATH. That's all—there are no external dependencies and nothing else you need to install.

If you use Node.js, you can also install Sass using npm by running

npm install -g sass

However, please note that this will install the pure JavaScript implementation of Sass, which runs somewhat slower than the other options listed here. But it has the same interface, so it'll be easy to swap in another implementation later if you need a bit more speed!

See the Sass website for more ways to install Sass.

Once you have Sass installed, you can run the sass executable to compile .sass and .scss files to .css files. For example:

sass source/stylesheets/index.scss build/stylesheets/index.css

Check out the Sass website for a guide on how to learn Sass!

This repository isn't an implementation of Sass. Those live in sass/dart-sass and sass/libsass. Instead, it contains:

• spec/, which contains specifications for language features.
• proposal/, which contains in-progress proposals for changes to the language.
• accepted/, which contains proposals that have been accepted and are either implemented or in the process of being implemented.

Note that this doesn't contain a full specification of Sass. Instead, feature specifications are written as needed when a new feature is being designed or when an implementor needs additional clarity about how something is supposed to work. This means many of the specs in spec/ only cover small portions of the features in question.

The proposals in this repository are versioned, to make it easy to track changes over time and to refer to older versions. Every version has a Git tag of the form proposal.<name>.draft-<version>. A new version should be created for each batch of changes.

Every version has a major version, and they may have a minor version as well (indicated <major>.<minor>). The minor version should be incremented for changes that don't affect the intended semantics of the proposal; otherwise, the major version should be incremented.