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postcss-nesting
Advanced tools
Package description
The postcss-nesting package is a PostCSS plugin that allows you to use nesting syntax in CSS, similar to what is offered by preprocessors like Sass and Less. It helps to write more readable and maintainable CSS by allowing styles to be nested within one another.
Nesting Rules
Allows nesting of selectors within a parent selector, which will be expanded to the equivalent of 'a b { color: black; }'.
a {
& b { color: black; }
}
Nesting Properties
Enables nesting of properties, which is useful for grouping font properties or other related properties together.
a {
font: {
weight: bold;
size: 1em;
family: serif;
}
}
Nesting At-Rules
Supports nesting of at-rules like @media within a selector, which will be processed into the correct CSS syntax.
a {
@media (min-width: 500px) {
color: black;
}
}
Similar to postcss-nesting, postcss-nested allows for nesting of selectors within CSS. It follows the nesting rules of preprocessors like Sass rather than the CSS Nesting Module.
This package includes postcss-nesting as one of its features, among other future CSS features, and allows you to use them in current browsers.
This is a syntax plugin for PostCSS that allows you to work with SCSS syntax, including nesting, but it does not compile SCSS. It's useful for linting SCSS with stylelint and PostCSS.
Readme
npm install postcss-nesting --save-dev
PostCSS Nesting lets you nest style rules inside each other, following the CSS Nesting specification.
If you want nested rules the same way Sass works you might want to use PostCSS Nested instead.
.foo {
color: red;
&:hover {
color: green;
}
> .bar {
color: blue;
}
@media (prefers-color-scheme: dark) {
color: cyan;
}
color: pink;
}
/* becomes */
.foo {
color: red;
color: pink;
}
.foo:hover {
color: green;
}
.foo > .bar {
color: blue;
}
@media (prefers-color-scheme: dark) {
.foo {
color: cyan;
}
}
Add PostCSS Nesting to your project:
npm install postcss postcss-nesting --save-dev
Use it as a PostCSS plugin:
const postcss = require('postcss');
const postcssNesting = require('postcss-nesting');
postcss([
postcssNesting(/* pluginOptions */)
]).process(YOUR_CSS /*, processOptions */);
PostCSS Nesting runs in all Node environments, with special instructions for:
@nest
has been removed from the specification.Previous iterations of the CSS Nesting specification required using @nest
for certain selectors.
@nest
was removed from the specification completely.
Future versions of this plugin will error if you use @nest
.
We advice everyone to migrate their codebase now to nested CSS without @nest
.
We published a Stylelint Plugin to help you migrate.
example warning:
@nest
was removed from the CSS Nesting specification and will be removed from PostCSS Nesting in the next major version. Change@nest foo & {}
tofoo & {}
to migrate to the latest standard.
You can silence this warning with a new silenceAtNestWarning
plugin option.
postcssNesting({
silenceAtNestWarning: true
})
The default behavior is to transpile CSS following an older version of the CSS nesting specification.
If you want to already use the latest version you can set the edition
option to 2024-02
.
postcssNesting({
edition: '2024-02'
})
2021
(default)This version is a continuation of what existed before CSS nesting was implemented in browsers.
It made a few non-invasive changes to keep up with implementations but it is falling behind.
In a future version of this plugin this will no longer be the default.
.foo {
color: red;
&:hover {
color: green;
}
> .bar {
color: blue;
}
@media (prefers-color-scheme: dark) {
color: cyan;
}
color: pink;
}
/* becomes */
.foo {
color: red;
color: pink;
}
.foo:hover {
color: green;
}
.foo > .bar {
color: blue;
}
@media (prefers-color-scheme: dark) {
.foo {
color: cyan;
}
}
2024-02
:is()
pseudo-class is no longer optionaland
keyword@nest
is removed from the specification.foo {
color: red;
&:hover {
color: green;
}
> .bar {
color: blue;
}
@media (prefers-color-scheme: dark) {
color: cyan;
}
color: pink;
}
/* becomes */
.foo {
color: red;
}
.foo:hover {
color: green;
}
.foo > .bar {
color: blue;
}
@media (prefers-color-scheme: dark) {
.foo {
color: cyan;
}
}
.foo {
color: pink;
}
Before :
#alpha,
.beta {
&:hover {
order: 1;
}
}
After without the option :
postcssNesting()
:is(#alpha,.beta):hover {
order: 1;
}
.beta:hover
has specificity as if .beta
where an id selector, matching the specification.
After with the option :
postcssNesting({
noIsPseudoSelector: true
})
#alpha:hover, .beta:hover {
order: 1;
}
.beta:hover
has specificity as if .beta
where a class selector, conflicting with the specification.
Before :
.alpha > .beta {
& + & {
order: 2;
}
}
After without the option :
postcssNesting()
:is(.alpha > .beta) + :is(.alpha > .beta) {
order: 2;
}
After with the option :
postcssNesting({
noIsPseudoSelector: true
})
.alpha > .beta + .alpha > .beta {
order: 2;
}
this is a different selector than expected as .beta + .alpha
matches .beta
followed by .alpha
.
avoid these cases when you disable :is()
writing the selector without nesting is advised here
/* without nesting */
.alpha > .beta + .beta {
order: 2;
}
FAQs
Nest rules inside each other in CSS
The npm package postcss-nesting receives a total of 6,478,586 weekly downloads. As such, postcss-nesting popularity was classified as popular.
We found that postcss-nesting demonstrated a healthy version release cadence and project activity because the last version was released less than a year ago. It has 3 open source maintainers collaborating on the project.
Did you know?
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