linaria: A JavaScript repository from que-etc

Zero-runtime CSS in JS library.

Features

Write CSS in JS, but with zero runtime, CSS is extracted to CSS files during build
Familiar CSS syntax with Sass like nesting
Use dynamic prop based styles with the React bindings, uses CSS variables behind the scenes
Easily find where the style was defined with CSS sourcemaps
Lint your CSS in JS with stylelint
Use JavaScript for logic, no CSS preprocessor needed

Installation

npm install linaria

yarn add linaria

Setup

Linaria currently supports webpack and Rollup to extract the CSS at build time. See Bundlers integration to configure your bundler.

Optionally, add the linaria/babel preset to your Babel configuration at the end of the presets list to avoid errors when importing the components in your server code or tests:

{
  "presets": [
    "@babel/preset-env",
    "@babel/preset-react",
    "linaria/babel"
  ]
}

See Configuration to customize how Linaria processes your files.

Syntax

Linaria can be used with any framework, with additional helpers for React. The basic syntax looks like this:

import { css } from 'linaria';
import { modularScale, hiDPI } from 'polished';
import fonts from './fonts';

// Write your styles in `css` tag
const header = css`
  text-transform: uppercase;
  font-family: ${fonts.heading};
  font-size: ${modularScale(2)};

  ${hiDPI(1.5)} {
    font-size: ${modularScale(2.5)};
  }
`;

// Then use it as a class name
<h1 class={header}>Hello world</h1>;

You can use imported variables and functions for logic inside the CSS code. They will be evaluated at build time.

If you're using React, you can use the styled helper, which makes it easy to write React components with dynamic styles with a styled-component like syntax:

import { styled } from 'linaria/react';
import { families, sizes } from './fonts';

// Write your styles in `styled` tag
const Title = styled.h1`
  font-family: ${families.serif};
`;

const Container = styled.div`
  font-size: ${sizes.medium}px;
  color: ${props => props.color};
  border: 1px solid red;

  &:hover {
    border-color: blue;
  }

  ${Title} {
    margin-bottom: 24px;
  }
`;

// Then use the resulting component
<Container color="#333">
  <Title>Hello world</Title>
</Container>;

Dynamic styles will be applied using CSS custom properties (aka CSS variables) and don't require any runtime.

Documentation

Trade-offs

No IE11 support when using dynamic styles in components with styled, since it uses CSS custom properties
Dynamic styles are not supported with css tag. See Dynamic styles with css tag for alternative approaches.
Modules used in the CSS rules cannot have side-effects. For example:
```
import { css } from 'linaria';
import colors from './colors';

const title = css`
  color: ${colors.text};
`;
```
Here, there should be no side-effects in the colors.js file, or any file it imports. We recommend to move helpers and shared configuration to files without any side-effects.

Editor Plugins

VSCode

Syntax Highlighting - language-babel
Autocompletion - vscode-styled-components
Linting - stylelint

Atom

Syntax Highlighting and Autocompletion - language-babel

Recommended Libraries

gatsby-plugin-linaria – Gatsby plugin that sets up Babel and webpack configuration for Linaria.
polished.js - A lightweight toolset for writing styles in JavaScript.