I read bootstrap’s 3 code and here I will factor out some of the main concepts that I have found at their stylesheet(css).
I read their stylesheet for educational purposes, and because after all I don’t like overriding their sheet, or have 200 classes that I will never use for my projects. I also don’t like including their js files, and it seems that many css classes have connections with the js code.
By reading bootstrap’s code for the first time I narrowed down the code from 6 thousand lines to 1.5 thousand. And here’s the most interesting teqniques they use: