Sass

CSS with superpowers — the most mature, stable, and powerful professional grade CSS extension.

Sass is the most mature, stable, and powerful professional grade CSS extension language in the world. It lets you use variables, nested rules, mixins, functions, and more, all with a fully CSS-compatible syntax. Sass helps keep large stylesheets well-organized and makes it easy to share design within and across projects. With over a decade of active development and a massive community, Sass remains the go-to choice for teams that need scalable, maintainable CSS architectures without sacrificing performance or compatibility.