[harlanji]

This is a great first step. It seems the next step toward usefulness is making it follow some script throughout the site as a build/optimize step to tease out the full set of rule usage (think Selenium on PhantomJS). Automatically finding all rule usage in a data-driven application would be an NP complete problem, but with proper direction from the developers this could be a viable tool. Even more so if it could map back to LESS/SASS rules, which I think would also need some brute forcing or at least hand holding. Nice work!