Discard duplicate rules in your CSS files with PostCSS.

Merge CSS rules with PostCSS.

PostCSS plugin to unwrap nested rules like how Sass does it

Normalize wrapping quotes for CSS string literals.

Ensure CSS selectors are unique.

Tokenize CSS

PostCSS plugin to import CSS files

Style form elements when they are empty

Use the overflow shorthand in CSS

Use cascade layers in CSS

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

Style elements relative to other elements in CSS

Normalize multiple value display syntaxes into single values.

Use the rebeccapurple color keyword in CSS

Normalize keyword values for position into length values.

Normalize unicode-range descriptors, and can convert to wildcard ranges.

Convert two value syntax for repeat-style into one value.

Use 4 & 8 character hex color notation in CSS

Nest rules inside each other in CSS

Safe defaults for cssnano which require minimal configuration.