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There is a lack of architectural specifications when it comes to CSS. The biggest reason for this is probably because developpers see CSS more as a tool than a language. For example, we can all use a pen to write a word and get the job done. But none of us will ever write that word exactly the same. Everyone has a unique writing style. This is the same when it comes to CSS. We all write the same keywords, but developers always end up writing their CSS in a different way.