Check out "Do you speak JavaScript?" - my latest video course on advanced JavaScript.
Language APIs, Popular Concepts, Design Patterns, Advanced Techniques In the Browser

variables

CSS variables are here for ages

Every front-end developer that starts reading about CSS preprocessors thinks “Oh, finally variables in CSS". Indeed, the ability to create and use variables in CSS makes our code much more flexible. However, I think that there is no need to use a preprocessor to create flexible stylesheets.

...read more