With the important thing, it's a matter of specificity. I've gotten in the habit of thinking about styles in layers of abstraction. When I'm working in a high level of abstraction, I keep it to a tag or a class. As I go lower down I add standard levels of specificity so the importance level changes (because 'div .class' will be inherited over '.class' every time). Class naming conventions help this too. If I know I'm overwriting an existing style, I often copy the existing style's rule exactly and just add 'html ' or 'div ' to the start of the rule out of habit.