Performance optimisations

CSS Level 3 namespaces

Parser for CSS Level 3 namespaces

CSS Level 3 media queries

Parser for CSS Level 3 media queries

Compress 2 matching pairs of horizontal and vertical units to 1 pair

Declarations like padding: 2px 5px 2px 5px; should get compressed to padding: 2px 5px;.

Better compatibility to CSS 2.1 4.2 Rules for handling parsing errors

See: CSS 2.1 4.2 Rules for handling parsing errors