|
|
# PostCSS Lab Function [<img src="https://postcss.github.io/postcss/logo.svg" alt="PostCSS Logo" width="90" height="90" align="right">][postcss] |
|
|
|
|
|
[<img alt="npm version" src="https://img.shields.io/npm/v/postcss-lab-function.svg" height="20">][npm-url] |
|
|
[<img alt="CSS Standard Status" src="https://cssdb.org/images/badges/lab-function.svg" height="20">][css-url] |
|
|
[<img alt="Build Status" src="https://github.com/csstools/postcss-plugins/workflows/test/badge.svg" height="20">][cli-url] |
|
|
[<img alt="Discord" src="https://shields.io/badge/Discord-5865F2?logo=discord&logoColor=white">][discord] |
|
|
|
|
|
|
|
|
[PostCSS Lab Function] lets you use `lab` and `lch` color functions in |
|
|
CSS, following the [CSS Color] specification. |
|
|
|
|
|
```pcss |
|
|
.color-lab { |
|
|
color: lab(40% 56.6 39); |
|
|
} |
|
|
|
|
|
.color-lch { |
|
|
color: lch(40% 68.735435 34.568626); |
|
|
} |
|
|
|
|
|
/* becomes */ |
|
|
|
|
|
.color { |
|
|
color: rgb(179, 35, 35); |
|
|
color: color(display-p3 0.64331 0.19245 0.16771); |
|
|
} |
|
|
|
|
|
.color-lch { |
|
|
color: rgb(179, 35, 35); |
|
|
color: color(display-p3 0.64331 0.19245 0.16771); |
|
|
} |
|
|
``` |
|
|
|
|
|
## Usage |
|
|
|
|
|
Add [PostCSS Lab Function] to your project: |
|
|
|
|
|
```bash |
|
|
npm install postcss postcss-lab-function --save-dev |
|
|
``` |
|
|
|
|
|
Use it as a [PostCSS] plugin: |
|
|
|
|
|
```js |
|
|
const postcss = require('postcss'); |
|
|
const postcssLabFunction = require('postcss-lab-function'); |
|
|
|
|
|
postcss([ |
|
|
postcssLabFunction(/* pluginOptions */) |
|
|
]).process(YOUR_CSS /*, processOptions */); |
|
|
``` |
|
|
|
|
|
[PostCSS Lab Function] runs in all Node environments, with special |
|
|
instructions for: |
|
|
|
|
|
| [Node](INSTALL.md#node) | [PostCSS CLI](INSTALL.md#postcss-cli) | [Webpack](INSTALL.md#webpack) | [Create React App](INSTALL.md#create-react-app) | [Gulp](INSTALL.md#gulp) | [Grunt](INSTALL.md#grunt) | |
|
|
| --- | --- | --- | --- | --- | --- | |
|
|
|
|
|
## Options |
|
|
|
|
|
### preserve |
|
|
|
|
|
The `preserve` option determines whether the original functional color notation |
|
|
is preserved. By default, it is not preserved. |
|
|
|
|
|
```js |
|
|
postcssLabFunction({ preserve: true }) |
|
|
``` |
|
|
|
|
|
```pcss |
|
|
.color { |
|
|
color: lab(40% 56.6 39); |
|
|
} |
|
|
|
|
|
/* becomes */ |
|
|
|
|
|
.color { |
|
|
color: rgb(179, 35, 35); |
|
|
color: color(display-p3 0.64331 0.19245 0.16771); |
|
|
color: lab(40% 56.6 39); |
|
|
} |
|
|
``` |
|
|
|
|
|
### enableProgressiveCustomProperties |
|
|
|
|
|
The `enableProgressiveCustomProperties` option determines whether the original notation |
|
|
is wrapped with `@supports` when used in Custom Properties. By default, it is enabled. |
|
|
|
|
|
⚠️ 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 |
|
|
postcssLabFunction({ enableProgressiveCustomProperties: false }) |
|
|
``` |
|
|
|
|
|
```pcss |
|
|
:root { |
|
|
--firebrick: lab(40% 56.6 39); |
|
|
} |
|
|
|
|
|
/* becomes */ |
|
|
|
|
|
:root { |
|
|
--firebrick: rgb(178, 34, 34); /* will never be used, not even in older browser */ |
|
|
--firebrick: color(display-p3 0.64331 0.19245 0.16771); /* will never be used, not even in older browser */ |
|
|
--firebrick: lab(40% 56.6 39); |
|
|
} |
|
|
``` |
|
|
|
|
|
### subFeatures |
|
|
|
|
|
#### displayP3 |
|
|
|
|
|
The `subFeatures.displayP3` option determines if `color(display-p3 ...)` is used as a fallback.<br> |
|
|
By default, it is enabled. |
|
|
|
|
|
`display-p3` can display wider gamut colors than `rgb` on some devices. |
|
|
|
|
|
```js |
|
|
postcssOKLabFunction({ |
|
|
subFeatures: { |
|
|
displayP3: false |
|
|
} |
|
|
}) |
|
|
``` |
|
|
|
|
|
```pcss |
|
|
.color { |
|
|
color: lab(40% 56.6 39); |
|
|
} |
|
|
|
|
|
/* becomes */ |
|
|
|
|
|
.color { |
|
|
color: rgb(179, 35, 35); |
|
|
color: lab(40% 56.6 39); |
|
|
} |
|
|
``` |
|
|
|
|
|
## Out of gamut colors |
|
|
|
|
|
Depending on the browser implementation out of gamut colors may be clipped, resulting in a different color.<br> |
|
|
Fallback values generated by [PostCSS Lab Function] are always mapped to a close alternative in sRGB. |
|
|
|
|
|
When setting `preserve` to `true` the original values will be used by some browsers and these may be clipped.<br> |
|
|
Certain browsers will have an incorrect color if this occurs. |
|
|
|
|
|
If the plugin detects out of gamut colors it will emit a warning : |
|
|
|
|
|
> "lch(95% 210 285)" is out of gamut for "display-p3". When "preserve: true" is set this will lead to unexpected results in some browsers. |
|
|
|
|
|
To resolve this warning you can use a color that is in gamut for `display-p3`. |
|
|
|
|
|
## Copyright : color conversions |
|
|
|
|
|
This software or document includes material copied from or derived from https://github.com/w3c/csswg-drafts/tree/main/css-color-4. Copyright © 2022 W3C® (MIT, ERCIM, Keio, Beihang). |
|
|
|
|
|
[cli-url]: https://github.com/csstools/postcss-plugins/actions/workflows/test.yml?query=workflow/test |
|
|
[css-url]: https://cssdb.org/#lab-function |
|
|
[discord]: https://discord.gg/bUadyRwkJS |
|
|
[npm-url]: https://www.npmjs.com/package/postcss-lab-function |
|
|
|
|
|
[CSS Color]: https://drafts.csswg.org/css-color/#specifying-lab-lch |
|
|
[Gulp PostCSS]: https://github.com/postcss/gulp-postcss |
|
|
[Grunt PostCSS]: https://github.com/nDmitry/grunt-postcss |
|
|
[PostCSS]: https://github.com/postcss/postcss |
|
|
[PostCSS Loader]: https://github.com/postcss/postcss-loader |
|
|
[PostCSS Lab Function]: https://github.com/csstools/postcss-plugins/tree/main/plugins/postcss-lab-function
|
|
|
|