# PostCSS HWB Function [
][PostCSS]
[
][npm-url] [
][cli-url] [
][discord]
[
][css-url] [
][css-url]
```bash
npm install @csstools/postcss-hwb-function --save-dev
```
[PostCSS HWB Function] lets you use the `hwb()` color function in CSS, following [CSS Color Module 4].
```css
a {
color: hwb(194 0% 0%);
}
b {
color: hwb(194 0% 0% / .5);
}
/* becomes */
a {
color: rgb(0, 196, 255);
}
b {
color: rgba(0, 196, 255, 0.5);
}
```
## Usage
Add [PostCSS HWB Function] to your project:
```bash
npm install postcss @csstools/postcss-hwb-function --save-dev
```
Use it as a [PostCSS] plugin:
```js
const postcss = require('postcss');
const postcssHWBFunction = require('@csstools/postcss-hwb-function');
postcss([
postcssHWBFunction(/* pluginOptions */)
]).process(YOUR_CSS /*, processOptions */);
```
[PostCSS HWB Function] runs in all Node environments, with special
instructions for:
- [Node](INSTALL.md#node)
- [PostCSS CLI](INSTALL.md#postcss-cli)
- [PostCSS Load Config](INSTALL.md#postcss-load-config)
- [Webpack](INSTALL.md#webpack)
- [Next.js](INSTALL.md#nextjs)
- [Gulp](INSTALL.md#gulp)
- [Grunt](INSTALL.md#grunt)
## Options
### preserve
The `preserve` option determines whether the original notation
is preserved. By default, it is not preserved.
```js
postcssHWBFunction({ preserve: true })
```
```css
a {
color: hwb(194 0% 0%);
}
b {
color: hwb(194 0% 0% / .5);
}
/* becomes */
a {
color: rgb(0, 196, 255);
color: hwb(194 0% 0%);
}
b {
color: rgba(0, 196, 255, 0.5);
color: hwb(194 0% 0% / .5);
}
```
[cli-url]: https://github.com/csstools/postcss-plugins/actions/workflows/test.yml?query=workflow/test
[css-url]: https://cssdb.org/#hwb-function
[discord]: https://discord.gg/bUadyRwkJS
[npm-url]: https://www.npmjs.com/package/@csstools/postcss-hwb-function
[PostCSS]: https://github.com/postcss/postcss
[PostCSS HWB Function]: https://github.com/csstools/postcss-plugins/tree/main/plugins/postcss-hwb-function
[CSS Color Module 4]: https://www.w3.org/TR/css-color-4/#the-hwb-notation