Lightning CSS is an incredibly fast CSS parser, transformer, bundler, and minifier written in Rust. It leverages modern browser features and optimizations to deliver smaller, more performant stylesheets. It's designed to be a drop-in replacement for existing CSS processing tools, enhancing the speed and efficiency of your front-end build process. Lightning CSS also offers powerful integrations with popular build systems and supports various CSS features, allowing for seamless adoption and improved web performance.