PostCSS

PostCSS is a tool for transforming styles with JS plugins. These plugins can lint your CSS, support variables and mixins, transpile future CSS syntax, inline images, and more.

PostCSS is used by industry leaders including Wikipedia, Twitter, Alibaba, and JetBrains. The Autoprefixer and Stylelint PostCSS plugins are some of the most popular CSS tools.

  Built by Evil Martians, go-to agency for developer tools.

Sponsorship

PostCSS needs your support. We are accepting donations at Open Collective.

<img src="https://www.atlascloud.ai/logo.svg"
   alt="Sponsored by Atlas Cloud" width="300" height="48">

Atlas Cloud is a full-modal AI inference platform that gives developers a single AI API to access video generation, image generation, and LLM APIs. Instead of managing multiple vendor integrations, you connect once and get unified access to 300+ curated models across all modalities.

Check out Atlas Cloud's new coding plan promotion for more budget-friendly API access.

Plugins

PostCSS takes a CSS file and provides an API to analyze and modify its rules (by transforming them into an Abstract Syntax Tree). This API can then be used by plugins to do a lot of useful things, e.g., to find errors automatically, or to insert vendor prefixes.

Currently, PostCSS has more than 200 plugins. You can find all of the plugins in the plugins list. Below is a list of our favorite plugins — the best demonstrations of what can be built on top of PostCSS.

If you have any new ideas, PostCSS plugin development is really easy.

Solve Global CSS Problem

• [postcss-use] allows you to explicitly set PostCSS plugins within CSS and execute them only for the current file.
• [postcss-modules] and [react-css-modules] automatically isolate selectors within components.
• [postcss-autoreset] is an alternative to using a global reset that is better for isolatable components.
• [postcss-initial] adds all: initial support, which resets all inherited styles.
• [cq-prolyfill] adds container query support, allowing styles that respond to the width of the parent.

Use Future CSS, Today

• [autoprefixer] adds vendor prefixes, using data from Can I Use.
• [postcss-preset-env] allows you to use future CSS features today.

Better CSS Readability

• [postcss-nested] unwraps nested rules the way Sass does.
• [postcss-sorting] sorts the content of rules and at-rules.
• [postcss-utilities] includes the most commonly used shortcuts and helpers.
• [short] adds and extends numerous shorthand properties.

Images and Fonts

• [postcss-url] postcss plugin to rebase url(), inline or copy asset.
• [postcss-sprites] generates image sprites.
• [font-magician] generates all the @font-face rules needed in CSS.
• [postcss-inline-svg] allows you to inline SVG and customize its styles.
• [postcss-write-svg] allows you to write simple SVG directly in your CSS.
• [webp-in-css] to use WebP image format in CSS background.
• [avif-in-css] to use AVIF image format in CSS background.

Linters

• [stylelint] is a modular stylesheet linter.
• [stylefmt] is a tool that automatically formats CSS according stylelint rules.
• [doiuse] lints CSS for browser support, using data from Can I Use.
• [colorguard] helps you maintain a consistent color palette.

Other

• [cssnano] is a modular CSS minifier.
• [lost] is a feature-rich calc() grid system.
• [rtlcss] mirrors styles for right-to-left locales.

Syntaxes

PostCSS can transform styles in any syntax, not just CSS. If there is not yet support for your favorite syntax, you can write a parser and/or stringifier to extend PostCSS.

• [sugarss] is a indent-based syntax like Sass or Stylus.
• [postcss-syntax] switch syntax automatically by file extensions.
• [postcss-html] parsing styles in <style> tags of HTML-like files.
• [postcss-markdown] parsing styles in code blocks of Markdown files.
• [postcss-styled-syntax] parses styles in template literals CSS-in-JS like styled-components.
• [postcss-jsx] parsing CSS in template / object literals of source files.
• [postcss-styled] parsing CSS in template literals of source files.
• [postcss-scss] allows you to work with SCSS (but does not compile SCSS to CSS).
• [postcss-sass] allows you to work with Sass (but does not compile Sass to CSS).
• [postcss-less] allows you to work with Less (but does not compile LESS to CSS).
• [postcss-less-engine] allows you to work with Less (and DOES compile LESS to CSS using true Less.js evaluation).
• [postcss-js] allows you to write styles in JS or transform React Inline Styles, Radium or JSS.
• [postcss-safe-parser] finds and fixes CSS syntax errors.
• [midas] converts a CSS string to highlighted HTML.

Articles

• Some things you may think about PostCSS… and you might be wrong
• What PostCSS Really Is; What It Really Does
• PostCSS Guides

More articles and videos you can find on awesome-postcss list.

Books

• Mastering PostCSS for Web Design by Alex Libby, Packt. (June 2016)

Usage

You can start using PostCSS in just two steps:

1. Find and add PostCSS extensions for your build tool.
2. Select plugins and add them to your PostCSS process.

CSS-in-JS

The best way to use PostCSS with CSS-in-JS is [astroturf]. Add its loader to your webpack.config.js:

module.exports = {
  module: {
    rules: [
      {
        test: /\.css$/,
        use: ['style-loader', 'postcss-loader']
      },
      {
        test: /\.jsx?$/,
        use: ['babel-loader', 'astroturf/loader']
      }
    ]
  }
}

Then create postcss.config.js:

/** @type {import('postcss-load-config').Config} */
const config = {
  plugins: [require('autoprefixer'), require('postcss-nested')]
}

module.exports = config

Parcel

Parcel has built-in PostCSS support. It already uses Autoprefixer and cssnano. If you want to change plugins, create postcss.config.js in project’s root:

/** @type {import('postcss-load-config').Config} */
const config = {
  plugins: [require('autoprefixer'), require('postcss-nested')]
}

module.exports = config

Parcel will even automatically install these plugins for you.

Please, be aware of the several issues in Version 1. Notice, Version 2 may resolve the issues via issue #2157.

Webpack

Use [postcss-loader] in webpack.config.js:

module.exports = {
  module: {
    rules: [
      {
        test: /\.css$/,
        exclude: /node_modules/,
        use: [
          {
            loader: 'style-loader'
          },
          {
            loader: 'css-loader',
            options: {
              importLoaders: 1
            }
          },
          {
            loader: 'postcss-loader'
          }
        ]
      }
    ]
  }
}

Then create postcss.config.js:

/** @type {import('postcss-load-config').Config} */
const config = {
  plugins: [require('autoprefixer'), require('postcss-nested')]
}

module.exports = config

Gulp

Use [gulp-postcss] and [gulp-sourcemaps].

gulp.task('css', () => {
  const postcss = require('gulp-postcss')
  const sourcemaps = require('gulp-sourcemaps')

  return gulp
    .src('src/**/*.css')
    .pipe(sourcemaps.init())
    .pipe(postcss([require('autoprefixer'), require('postcss-nested')]))
    .pipe(sourcemaps.write('.'))
    .pipe(gulp.dest('build/'))
})

npm Scripts

To use PostCSS from your command-line interface or with npm scripts there is [postcss-cli].

postcss --use autoprefixer -o main.css css/*.css

Browser

If you want to compile CSS string in browser (for instance, in live edit tools like CodePen), just use Browserify or webpack. They will pack PostCSS and plugins files into a single file.

To apply PostCSS plugins to React Inline Styles, JSS, Radium and other CSS-in-JS, you can use [postcss-js] and transforms style objects.

const postcss = require('postcss-js')
const prefixer = postcss.sync([require('autoprefixer')])

prefixer({ display: 'flex' }) //=> { display: ['-webkit-box', '-webkit-flex', '-ms-flexbox', 'flex'] }

Runners

• Grunt: @lodder/grunt-postcss
• HTML: posthtml-postcss
• Stylus: poststylus
• Rollup: rollup-plugin-postcss
• Brunch: [postcss-brunch](https://githu