Modular CSS
http://www.contentwithstyle.co.uk/Articles/12/modular-css

Stenhouse, Mike
Content with Style
2005

Abstract:

This isn't a new idea but looking at people's code it doesn't seem to be a particularly widely used practice: modular CSS. That's a poncy name for the very simple idea of grouping related styles into separate stylesheets. The same set of tasks turn up on project after project and a little careful thought can save hours of foundation work, allowing you to get on with the serious business of turning a flat design into a web page far more quickly.