CSS Preprocessors and frameworks are a big one. As well as learning in depth responsive development. Wrote a little about it here: fullbit.ca/2018-full-stack-develop... but that might not go as deep as you are looking.
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CSS Preprocessors and frameworks are a big one. As well as learning in depth responsive development. Wrote a little about it here: fullbit.ca/2018-full-stack-develop... but that might not go as deep as you are looking.