• The version in 🇺🇦 ukrainean
• CI runs log for the "main" branch

PostCSS plugin to boost (increase) the specificity of CSS selectors.

It is hugely inspired by MadLittleMods/postcss-increase-specificity but it is not a copy, it has a different API and the code is written from scratch.

The reason I created it was that the author does not support the initial plugin and it uses outdated dependencies.

npm install -D postcss-boost-specificity

After that please, add the plugin to your postcss configuration file or use it when you call postcss.

Basically, it adds an additional selector to each of the existing selectors to improve their weight.

Initial CSS:

html {
  background: #bada55;
}

.batman {
  background: #fff;
}

#main-hero {
  color: red;
}

[id="main-hero"] {
  text-transform: uppercase;
}

html[data-whatintent="keyboard"] .button:focus {
  background-color: #bada55;
}

Result CSS:

html:not(#\9):not(#\9):not(#\9) {
  background: #bada55;
}

:not(#\9):not(#\9):not(#\9) .batman {
  background: #fff;
}

:not(#\9):not(#\9):not(#\9) #main-hero {
  color: red;
}

:not(#\9):not(#\9):not(#\9) [id="main-hero"] {
  text-transform: uppercase;
}

html[data-whatintent="keyboard"] .button:focus:not(#\9):not(#\9):not(#\9) {
  background-color: #bada55;
}

• By default it uses :not(#\9) selector and adds it to your selector. But you can provide your substitute. Here you can find all the discussion related to it What is the most character-efficient way to increase CSS specificity?

We prepared a Demo you can run locally. Just don't forget to run npm install beforehand.

• All the code for it is inside demo/index.js file.
• It takes CSS code from demo/test.css file, processes it, and puts results to the demo/results/test.result.css file.
• npm run demo script runs this demo
• demo/results/test.result.css is in .gitignore, so you can generate it by yourself.

• booster: a string, CSS selector to prepend (append for root selectors like html, :root, :host) to each of your selectors.

  • the default value is: :not(#\9). It increases specificity by id for each repeated time.
    • Warning: The default value is :not(#\9) pseudo-class selector is not supported in IE browsers. If it is an issue for you, please provide the substitute.
  • An empty string or a string only from spaces are ignored, the default value is used instead;

    let badBooster1 = "";
    let badBooster2 = "     "; // These values are ignored

• repeatTimes: a number, that says how many times to repeat options.booster for your selectors

  • the default value is: 3
  • NaN, Infinity, and -Infinity values are ignored, the default value is used instead;

    let badRepeatTimes1 = NaN;
    let badRepeatTimes2 = Infinity;
    let badRepeatTimes3 = -Infinity;
    // These values are ignored

To be able to contribute you may require to do some local setup.

0. Fork the project under your own GitHub account.
1. Clone the project.
2. You must have Node.js and NPM installed locally.
3. Run the npm install command in the project folder.

After the setup please follow the instructions from the contributing guide.

Also, please check up on our awesome NPM scripts below.

• npm test: run tests
• npm run lint: run ESLint check of the code
• npm run test:watch: run tests in a "watch" mode
• npm run demo: run demo example
• npm run npm:publish:beta: publish the package to NPM registry with the beta tag