If you are looking for documentation to improve your CSS skills I suggest you to take a look at the following 5 must read presentations about CSS coding. The following presentations help you learn how to write efficient and maintainable CSS code, understand secrets of CSS inheritance, line-height and CSS System approach a practical way to write high-quality, reusable CSS code with a shared vocabulary for developers, learn Object Oriented CSS in order to develop high performance web applications and websites. Good reading!
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