xCSS : xCSS bases on CSS and empowers a straightforward and object-oriented workflow when developing complex style cascades.
YAML Builder : A tool for visual layout development of YAML based CSS layouts
YAML : A modular CSS framework for truly flexible, accessible and responsive websites
A utility-first CSS framework packed with classes like flex, pt-4, text-center and rotate-90 that can be composed to build any design, directly in your markup.