3.6 KiB
PostCSS Focus Within
PostCSS Focus Within lets you use the :focus-within
pseudo-class in CSS,
following the Selectors Level 4 specification.
It is the companion to the focus-within polyfill.
.my-form-field:focus-within label {
background-color: yellow;
}
/* becomes */
.my-form-field[focus-within] label {
background-color: yellow;
}
.my-form-field:focus-within label {
background-color: yellow;
}
PostCSS Focus Within duplicates rules using the :focus-within
pseudo-class
with a [focus-within]
attribute selector, the same selector used by the
focus-within polyfill. This replacement selector can be changed using the
replaceWith
option. Also, the preservation of the original :focus-within
rule can be disabled using the preserve
option.
Usage
Add PostCSS Focus Within to your project:
npm install postcss-focus-within --save-dev
Use PostCSS Focus Within to process your CSS:
const postcssFocusWithin = require('postcss-focus-within');
postcssFocusWithin.process(YOUR_CSS /*, processOptions, pluginOptions */);
Or use it as a PostCSS plugin:
const postcss = require('postcss');
const postcssFocusWithin = require('postcss-focus-within');
postcss([
postcssFocusWithin(/* pluginOptions */)
]).process(YOUR_CSS /*, processOptions */);
PostCSS Focus Within runs in all Node environments, with special instructions for:
Node | PostCSS CLI | Webpack | Create React App | Gulp | Grunt |
---|
Options
preserve
The preserve
option defines whether the original selector should remain. By
default, the original selector is preserved.
focusWithin({ preserve: false });
.my-form-field:focus-within label {
background-color: yellow;
}
/* becomes */
.my-form-field[focus-within] label {
background-color: yellow;
}
replaceWith
The replaceWith
option defines the selector to replace :focus-within
. By
default, the replacement selector is [focus-within]
.
focusWithin({ replaceWith: '.focus-within' });
.my-form-field:focus-within label {
background-color: yellow;
}
/* becomes */
.my-form-field.focus-within label {
background-color: yellow;
}
.my-form-field:focus-within label {
background-color: yellow;
}