Lightning CSS

Lightning CSS is an exceptionally fast CSS parser, transformer, and minifier written in Rust, primarily maintained by the Parcel team. Currently at version 1.32.0, it undergoes active development with frequent minor and patch releases, ensuring up-to-date feature support and performance improvements. Its key differentiators include leveraging Rust for unparalleled performance, a browser-grade parser (based on Mozilla's `cssparser` and `selectors` crates), and sophisticated typed property values that ensure consistent and accurate transformations across various CSS features. Beyond basic minification, it performs advanced optimizations such as combining longhand properties into shorthands, merging adjacent rules, and reducing `calc()` expressions. It also provides robust vendor prefixing based on configurable browser targets (integrating with Browserslist) and comprehensive syntax lowering for modern CSS features like CSS Nesting, Custom Media Queries, and advanced Color Level 4/5 functions, enabling developers to write modern CSS while ensuring broad browser compatibility and optimized output size.