CSS, like any widely-used technology — and it is widely used because there is basically no way to make web pages without it — has developed around it an entire ecosystem and even, one might say, mythology, as well as a number of anti-patterns which have unfortunately taken root. According to Wikipedia, an anti-pattern is

a common response to a recurring problem that is usually ineffective and risks being highly counterproductive.

My point in noting these anti-patterns is not to criticize (OK, it is a little bit), but to learn from what they can teach us about CSS. Warning…