Normalize URLs with PostCSS

Ensure CSS selectors are unique.

Use the :focus-visible pseudo-selector in CSS

Nest rules inside each other in CSS

Merge longhand properties into shorthand with PostCSS.

PostCSS plugin to transform percentage-based opacity values to more compatible floating-point values.

PostCSS plugin to transform :not() W3C CSS level 4 pseudo class to :not() CSS level 3 selectors

Use a place-* shorthand for align-* and justify-* in CSS

Use unquoted format on @font-face CSS definitions.

Use Custom Selectors in CSS

Use the rebeccapurple color keyword in CSS

Discard comments in your CSS files with PostCSS.

Discard duplicate rules in your CSS files with PostCSS.

Use 4 & 8 character hex color notation in CSS

Use the ic length unit

Use two values display syntax for inner and outer display types.

Library will help you to detect if the locale is right-to-left language.

PostCSS plugin to transform clamp() to combination of min/max

Use the :any-link pseudo-class in CSS

PostCSS plugin to transform W3C font-variant properties to more compatible CSS (font-feature-settings)