npm install @csstools/postcss-contrast-color-function --save-dev

PostCSS Contrast Color Function lets you dynamically specify a text color with adequate contrast following the CSS Color 5 Specification.

.color {
	color: contrast-color(oklch(82% 0.2 330));
}

/* becomes */

.color {
	color: rgb(0, 0, 0);
	color: contrast-color(oklch(82% 0.2 330));
}

Add PostCSS Contrast Color Function to your project:

npm install postcss @csstools/postcss-contrast-color-function --save-dev

Use it as a PostCSS plugin:

const postcss = require('postcss');
const postcssContrastColorFunction = require('@csstools/postcss-contrast-color-function');

postcss([
	postcssContrastColorFunction(/* pluginOptions */)
]).process(YOUR_CSS /*, processOptions */);

PostCSS Contrast Color Function runs in all Node environments, with special instructions for:

• Node
• PostCSS CLI
• PostCSS Load Config
• Webpack
• Next.js
• Gulp
• Grunt

The preserve option determines whether the original notation is preserved. By default, it is preserved.

postcssContrastColorFunction({ preserve: false })

.color {
	color: contrast-color(oklch(82% 0.2 330));
}

/* becomes */

.color {
	color: rgb(0, 0, 0);
}