In our current project instead of putting the framework's html/css into our codebase I'm outputting as bare bones html as I can with semantic class names on everything and then mapping those classes to the framework using sass mixins/extends/includes.

To make a RWD site I'm having to rewrite a lot of the framework to be mixins instead of classes so that I can use them in @media as SASS doesn't allow @extend in @media any more[1]. What I'd find really useful would be a framework thats entirely built from mixins/partials and outputs no css until you create your own classes that use them.

[1]: https://github.com/nex3/sass/issues/154 Disallow @extend within directives