PostCSS Selector Not

 npm install postcss-selector-not --save-dev

PostCSS Selector Not transforms :not() W3C CSS level 4 pseudo classes to :not() CSS level 3 selectors following the Selectors 4 Specification.

p:not(:first-child, .special) {
	color: red;
}

/* becomes */

p:not(:first-child):not(.special) {
	color: red;
}

[!CAUTION]
Only lists of simple selectors (:not(.a, .b)) will work as expected.
Complex selectors (:not(.a > .b, .c ~ .d)) can not be downgraded.

Usage

Add PostCSS Selector Not to your project:

 npm install postcss postcss-selector-not --save-dev

Use it as a PostCSS plugin:

 const postcss = require('postcss');
const postcssSelectorNot = require('postcss-selector-not');

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

PostCSS Selector Not runs in all Node environments, with special
instructions for:

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