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npm · #3142 most downloaded on npm
Use Custom Properties Queries in CSS
Last release 2 days ago
02 Oct 2026
Release timing varies
gaps range from 8 days to 7 months
Nearly every release is documented
notes for 58 of the last 60 stable releases
Nothing withdrawn
no release was ever pulled
12 years old
99 releases · first in 2014
Share a single expansion budget across all declarations.
October 2, 2026
@function bodies.Updated `@csstools/css-parser-algorithms` to `4.0.2` (patch)
October 1, 2026
@csstools/css-parser-algorithms to 4.0.2 (patch)@csstools/cascade-layer-name-parser to 3.0.2 (patch)One column per quarter.
Improve performance and avoid a stack overflow when sorting a long chain of custom properties
September 25, 2026
@layer rules@layer nesting exceeds a safe depth@csstools/css-tokenizer to 4.0.1 (patch)@csstools/css-tokenizer to 4.0.2 (patch)@csstools/css-parser-algorithms to 4.0.1 (patch)@csstools/cascade-layer-name-parser to 3.0.1 (patch)Fix importance of custom media in anonymous cascade layers.
February 21, 2026
Updated: Support for Node 20.19.0 or later (major).
January 14, 2026
20.19.0 or later (major).commonjs API. In supported Node versions require(esm) will work without needing to make code changes.@csstools/css-tokenizer to 4.0.0 (major)@csstools/utilities to 3.0.0 (major)@csstools/css-parser-algorithms to 4.0.0 (major)@csstools/cascade-layer-name-parser to 3.0.0 (major)Fix infinite loop for comments that contain variables (e.g. var(--foo) /* var(--bar) */)
June 5, 2025
var(--foo) /* var(--bar) */)Improve the implementation of how comments are preserved when transpiling
May 27, 2025
@csstools/css-tokenizer to 3.0.4 (patch)@csstools/css-parser-algorithms to 3.0.5 (patch)@csstools/cascade-layer-name-parser to 2.0.5 (patch)Updated `@csstools/css-tokenizer` to `3.0.3` (patch)
November 1, 2024
@csstools/css-tokenizer to 3.0.3 (patch)@csstools/css-parser-algorithms to 3.0.4 (patch)@csstools/cascade-layer-name-parser to 2.0.4 (patch)Updated `@csstools/css-parser-algorithms` to `3.0.3` (patch)
October 23, 2024
@csstools/css-parser-algorithms to 3.0.3 (patch)@csstools/cascade-layer-name-parser to 2.0.3 (patch)Updated `@csstools/css-tokenizer` to `3.0.2` (patch)
October 10, 2024
@csstools/css-tokenizer to 3.0.2 (patch)@csstools/css-parser-algorithms to 3.0.2 (patch)@csstools/cascade-layer-name-parser to 2.0.2 (patch)Updated `@csstools/css-tokenizer` to `3.0.1` (patch)
August 18, 2024
@csstools/css-tokenizer to 3.0.1 (patch)@csstools/css-parser-algorithms to 3.0.1 (patch)@csstools/cascade-layer-name-parser to 2.0.1 (patch)Updated: Support for Node v18+ (major).
August 3, 2024
@csstools/css-tokenizer to 3.0.0 (major)@csstools/utilities to 2.0.0 (major)@csstools/css-parser-algorithms to 3.0.0 (major)@csstools/cascade-layer-name-parser to 2.0.0 (major)Updated `@csstools/css-tokenizer` to `2.4.1` (patch)
July 6, 2024
@csstools/css-tokenizer to 2.4.1 (patch)@csstools/css-parser-algorithms to 2.7.1 (patch)@csstools/cascade-layer-name-parser to 1.0.13 (patch)Updated `@csstools/css-tokenizer` to `2.3.2` (patch)
June 29, 2024
@csstools/css-tokenizer to 2.3.2 (patch)@csstools/css-parser-algorithms to 2.7.0 (minor)@csstools/cascade-layer-name-parser to 1.0.12 (patch)Updated `@csstools/css-tokenizer` to `2.3.1` (patch)
May 4, 2024
@csstools/css-tokenizer to 2.3.1 (patch)@csstools/css-parser-algorithms to 2.6.3 (patch)@csstools/cascade-layer-name-parser to 1.0.11 (patch)Updated `@csstools/css-tokenizer` to `2.3.0` (minor)
May 4, 2024
@csstools/css-tokenizer to 2.3.0 (minor)@csstools/css-parser-algorithms to 2.6.2 (patch)@csstools/cascade-layer-name-parser to 1.0.10 (patch)Fix an error when a custom property has multiple dependencies and one of them is undefined
Improve handling of cross references between computed values of custom properties
April 11, 2024
Updated `@csstools/css-tokenizer` to `2.2.4` (patch)
March 13, 2024
@csstools/css-tokenizer to 2.2.4 (patch)@csstools/css-parser-algorithms to 2.6.1 (patch)@csstools/cascade-layer-name-parser to 1.0.9 (patch)Reuse code with @csstools/utilities
February 19, 2024
@csstools/utilities@csstools/css-parser-algorithms to 2.6.0 (minor)@csstools/cascade-layer-name-parser to 1.0.8 (patch)Updated `@csstools/css-tokenizer` to `2.2.3` (patch)
December 31, 2023
@csstools/css-tokenizer to 2.2.3 (patch)@csstools/css-parser-algorithms to 2.5.0 (minor)@csstools/cascade-layer-name-parser to 1.0.7 (patch)Updated `@csstools/css-tokenizer` to `2.2.2` (patch)
December 15, 2023
@csstools/css-tokenizer to 2.2.2 (patch)@csstools/css-parser-algorithms to 2.4.0 (minor)@csstools/cascade-layer-name-parser to 1.0.6 (patch)Updated `@csstools/css-tokenizer` to `2.2.1` (patch)
September 24, 2023
@csstools/css-tokenizer to 2.2.1 (patch)@csstools/css-parser-algorithms to 2.3.2 (patch)@csstools/cascade-layer-name-parser to 1.0.5 (patch)_September 18, 2023_ - Improve performance
September 18, 2023
Added: support for :where(html) and :where(:root) selectors
July 24, 2023
:where(html) and :where(:root) selectors@csstools/css-tokenizer to 2.2.0 (minor)@csstools/css-parser-algorithms to 2.3.1 (patch)@csstools/cascade-layer-name-parser to 1.0.4 (patch)Updated `@csstools/css-parser-algorithms` to `2.3.0` (minor)
July 3, 2023
@csstools/css-parser-algorithms to 2.3.0 (minor)@csstools/cascade-layer-name-parser to 1.0.3 (patch)Do not generate fallback values when the rule is wrapped in @supports (top: var(--f)).
June 1, 2023
@supports (top: var(--f)).Updated @csstools/css-tokenizer to 2.1.1 (patch)
April 10, 2023
@csstools/css-tokenizer to 2.1.1 (patch)@csstools/css-parser-algorithms to 2.1.1 (patch)@csstools/cascade-layer-name-parser to 1.0.2 (patch)Fixed: exception on chained variable declarations.
February 21, 2023
Fixed: exception on missing variables.
February 8, 2023
Do not apply fallback values when these contain unresolvable custom properties.
February 7, 2023
Improve types declaration in package.json
January 28, 2023
types declaration in package.jsonAdded: Support for Cascade Layers.
January 24, 2023
v12.1.11)Updated: Support for Node v14+ (major).
November 14, 2022
importFrom feature (breaking).exportTo feature (breaking)..example {
--a-value: 20px;
margin: var(--a-value);
}
/* becomes */
.example {
--a-value: 20px;
margin: 20px;
margin: var(--a-value);
}
_December 1, 2022_ - Improve plugin performance
December 1, 2022
Fix how preserve: false interacts with logic around duplicate code (see 12.1.9).
October 20, 2022
preserve: false interacts with logic around duplicate code (see 12.1.9).:root {
--my-order: 1;
}
.foo {
order: 1;
order: var(--my-order);
}
/* With `preserve: false` : */
.foo {
order: 1;
}
Prevent duplicate code generation.
September 14, 2022
.foo {
order: 1;
order: var(--my-order, 1);
}
/* becomes */
.foo {
order: 1;
- order: 1;
order: var(--my-order, 1);
}
Remove some unneeded regular expressions.
June 10, 2022
Fix racing condition that could happen when using other async PostCSS plugins
April 8, 2022
Fix var() fallback value downgrades with value lists.
April 5, 2022
var() fallback value downgrades with value lists.Add deprecation notice for importFrom and exportTo
Fix .mjs in importFrom when using export default
January 31, 2022
.mjs in importFrom when using export default.mjs in importFrom on WindowsReset plugin state after each process. It is now safe to use the plugin multiple times for different processes or when watching.
January 17, 2022
Avoid throwing errors on unexpected option objects.
January 12, 2022
_January 12, 2022_ - Fix Node 12/14 compatibility
January 12, 2022
Add overrideImportFromWithRoot option
January 12, 2022
overrideImportFromWithRoot option.mjs in importFromFixed an issue that was causing synchronous mode to not being able to pick and transform properties that were added as part of the PostCSS flow.
January 7, 2022
Nothing published for this version
Removed Sourcemaps from package tarball.
January 2, 2022
Changed: now uses postcss-value-parser for parsing.
December 16, 2021
postcss-value-parser for parsing.Updated: Support for PostCS 8+ (major).
September 17, 2021
_January 12, 2021_ - Added: Support for PostCSS v8.
January 12, 2021
Breaking Change: Node v10+ now required
September 18, 2020
url-regex vulnerability (#228)Added: Export variables to SCSS file
Fixed: Preserve spaces in multi-part values
February 20, 2020
Updated: postcss-values-parser to 3.0.5 (patch)
July 15, 2019
postcss-values-parser to 3.0.5 (patch)Updated: postcss-values-parser to 3.0.4 (major)
June 20, 2019
postcss-values-parser to 3.0.4 (major)This release is identical to v9.0.0, only
npm publishfailed to publish v9.0.0 and threw the following error:You cannot publish over the previously published versions: 9.0.0.I did not want this issue to distract me, and so I thoughtfully and impatiently published v9.0.0 as v9.0.1.
Nothing published for this version
Added: Synchronous transforms when async is unnecessary (thank @eteeselink)
June 20, 2019
Added: Support for ignoring lines and or blocks using postcss-custom-properties comments.
April 1, 2019
postcss-custom-properties comments.postcss to 7.0.14 (patch)postcss-values-parser to 2.0.1 (patch)Your coding agent can read these notes before it upgrades. Set up the MCP server →