# PostCSS Color Functional Notation [
][PostCSS]
[
][npm-url] [
][cli-url] [
][discord]
[
][css-url] [
][css-url]
```bash
npm install postcss-color-functional-notation --save-dev
```
[PostCSS Color Functional Notation] lets you use space and slash separated
color notation in CSS, following the [CSS Color] specification.
```pcss
:root {
--firebrick: rgb(178 34 34);
--firebrick-a50: rgb(70% 13.5% 13.5% / 50%);
--firebrick-hsl: hsla(0 68% 42%);
--firebrick-hsl-a50: hsl(0 68% 42% / 50%);
}
/* becomes */
:root {
--firebrick: rgb(178, 34, 34);
--firebrick-a50: rgba(179, 34, 34, 0.5);
--firebrick-hsl: hsl(0, 68%, 42%);
--firebrick-hsl-a50: hsla(0, 68%, 42%, 0.5);
}
```
## Usage
Add [PostCSS Color Functional Notation] to your project:
```bash
npm install postcss postcss-color-functional-notation --save-dev
```
Use it as a [PostCSS] plugin:
```js
const postcss = require('postcss');
const postcssColorFunctionalNotation = require('postcss-color-functional-notation');
postcss([
postcssColorFunctionalNotation(/* pluginOptions */)
]).process(YOUR_CSS /*, processOptions */);
```
[PostCSS Color Functional Notation] 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
postcssColorFunctionalNotation({ preserve: true })
```
```pcss
:root {
--firebrick: rgb(178 34 34);
--firebrick-a50: rgb(70% 13.5% 13.5% / 50%);
--firebrick-hsl: hsla(0 68% 42%);
--firebrick-hsl-a50: hsl(0 68% 42% / 50%);
}
/* becomes */
:root {
--firebrick: rgb(178, 34, 34);
--firebrick-a50: rgba(179, 34, 34, 0.5);
--firebrick-hsl: hsl(0, 68%, 42%);
--firebrick-hsl: hsla(0 68% 42%);
--firebrick-hsl-a50: hsla(0, 68%, 42%, 0.5);
}
@supports (color: rgb(0 0 0 / 0)) {
:root {
--firebrick: rgb(178 34 34);
--firebrick-a50: rgb(70% 13.5% 13.5% / 50%);
}
}
@supports (color: hsl(0 0% 0% / 0)) {
:root {
--firebrick-hsl-a50: hsl(0 68% 42% / 50%);
}
}
```
### enableProgressiveCustomProperties
The `enableProgressiveCustomProperties` option determines whether the original notation
is wrapped with `@supports` when used in Custom Properties. By default, it is enabled.
> [!NOTE]
> We only recommend disabling this when you set `preserve` to `false` or if you bring your own fix for Custom Properties.
> See what the plugin does in its [README](https://github.com/csstools/postcss-plugins/tree/main/plugins/postcss-progressive-custom-properties#readme).
```js
postcssColorFunctionalNotation({ enableProgressiveCustomProperties: false })
```
```pcss
:root {
--firebrick: rgb(178 34 34);
--firebrick-a50: rgb(70% 13.5% 13.5% / 50%);
--firebrick-hsl: hsla(0 68% 42%);
--firebrick-hsl-a50: hsl(0 68% 42% / 50%);
}
/* becomes */
:root {
--firebrick: rgb(178, 34, 34);
--firebrick: rgb(178 34 34);
--firebrick-a50: rgba(179, 34, 34, 0.5);
--firebrick-a50: rgb(70% 13.5% 13.5% / 50%);
--firebrick-hsl: hsl(0, 68%, 42%);
--firebrick-hsl: hsla(0 68% 42%);
--firebrick-hsl-a50: hsla(0, 68%, 42%, 0.5);
--firebrick-hsl-a50: hsl(0 68% 42% / 50%);
}
```
_Custom properties do not fallback to the previous declaration_
[cli-url]: https://github.com/csstools/postcss-plugins/actions/workflows/test.yml?query=workflow/test
[css-url]: https://cssdb.org/#color-functional-notation
[discord]: https://discord.gg/bUadyRwkJS
[npm-url]: https://www.npmjs.com/package/postcss-color-functional-notation
[PostCSS]: https://github.com/postcss/postcss
[PostCSS Color Functional Notation]: https://github.com/csstools/postcss-plugins/tree/main/plugins/postcss-color-functional-notation
[CSS Color]: https://www.w3.org/TR/css-color-4/#funcdef-rgb