postcss-zindex

What is postcss-zindex?

The postcss-zindex package is a PostCSS plugin that reduces z-index values in your CSS files. It helps to minimize the number of different z-index values used, making your CSS more maintainable and reducing the risk of z-index conflicts.

What are postcss-zindex's main functionalities?

Reduce z-index values

This feature reduces the z-index values in your CSS to a smaller range, making it easier to manage and reducing the likelihood of conflicts.

/* Input CSS */
body {
  z-index: 10;
}
.header {
  z-index: 100;
}
.footer {
  z-index: 1000;
}

/* Output CSS after postcss-zindex */
body {
  z-index: 1;
}
.header {
  z-index: 2;
}
.footer {
  z-index: 3;
}

Other packages similar to postcss-zindex

postcss-sorting

The postcss-sorting package sorts CSS rules content with specified order. While it doesn't specifically target z-index values, it helps in organizing CSS properties, which can indirectly help in managing z-index values by keeping the CSS more structured.

postcss-merge-rules

The postcss-merge-rules package merges adjacent CSS rules with identical selectors. This can help reduce redundancy in your CSS, similar to how postcss-zindex reduces the number of z-index values. However, it focuses on merging rules rather than specifically targeting z-index values.

postcss-combine-duplicated-selectors

The postcss-combine-duplicated-selectors package combines duplicated CSS selectors into one. This helps in reducing the size of the CSS and making it more maintainable, similar to how postcss-zindex reduces z-index values. However, it focuses on combining selectors rather than z-index values.

README

postcss-zindex

Reduce z-index values with PostCSS.

Install

With npm do:

npm install postcss-zindex --save

Example

Sometimes, you may introduce z-index values into your CSS that are larger than necessary, in order to improve your understanding of how each stack relates to the others. For example, you might have a modal overlay at 5000 and the dialog for it at 5500 - so that modal classes occupy the 5xxx space.

But in production, it is unnecessary to use such large values for z-index where smaller values would suffice. This module will reduce all z-index declarations whilst respecting your original intent; such that the overlay becomes 1 and the dialog becomes 2. For more examples, see the tests.

Input

.modal {
    z-index: 5000
}

.modal-overlay {
    z-index: 5500
}

Output

.modal {
    z-index: 1
}

.modal-overlay {
    z-index: 2
}

Note that this module does not attempt to normalize relative z-index values, such as -1; indeed, it will abort immediately when encountering these values as it cannot be sure that rebasing mixed positive & negative values will keep the stacking context intact. Be careful with using this module alongside JavaScript injected CSS; ideally you should have already extracted all of your stacking context into CSS.

Usage

See the PostCSS documentation for examples for your environment.

Contributing

Pull requests are welcome. If you add functionality, then please add unit tests to cover it.

License

MIT © Ben Briggs