What Was Compass?
Compass was a CSS-Authoring framework for Sass. It provided Sass mixins and other functionality that helped you kickstart a website quickly. For full details, see the official documentation.
WARNING:
Compass is no longer actively developed. You should not use it for new projects. Consider TailwindCSS or Bourbon instead, which are also part of CodeKit.
Compass was end-of-lifed in 2016 and CodeKit has maintained support for it for 5+ years. This support will be completely removed in a future version of CodeKit, so you should migrate your old Compass projects to a modern framework.