Component-based CSS using Interoperable CSS + Sass, importing your CSS into JS but then using a build system to extract all of your component CSS into it's own

Component-based CSS using Interoperable CSS + Sass, importing your CSS into JS but then using a build system to extract all of your component CSS into it's own set of files to allow for caching. It's a complicated pipeline but it's pretty unbeatable when it comes to writing DRY, reusable, maintainable code. Everything is namespaced automatically and you can go from writing unweildly BEM class names to short, succinct and descriptive classes.