Principles such as DRY (don’t repeat yourself) are not present in CSS.
DRY states that “Every piece of knowledge must have a single, unambiguous, authoritative representation within a system.” This applies not only to code but to every aspect of a product, such as design itself. When DRY principles are followed, we’re supposed to end up with products that are of higher quality and easier to maintain.
We CSS authors don’t think of the cost of maintenance or the increased complexity that duplication and cancelling out of styles add to our CSS sheets.
We usually follow something closer to WET: we enjoy typing. Why someone would want to hand-code vendor prefixes for CSS gradients is beyond my understanding, but the truth is that some people do, and they take pride in it.
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