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What's your opinion on beginners learning CSS preprocessors without learning CSS properly? Do you think it'll help them?
I do think it helps, but I know there's a vibrant discussion within the community on this. In my opinion, it's easy to get stuck in the weeds and lose your momentum when you're first learning CSS. With Sass you can find your stride sooner even if you don't fully grok what's going on under the covers. And then, over time, you can read various mixin definitions and see how they work. I think it's good scaffolding for learning but it really depends on if you're a project based learner or a first-principles based learner.