Maybe the (highest level of) basics, but as someone who's been in the industry 21 years and manages all hiring for front-end, the one area of front-end that everyone seems to think is easy but also one of the rarest skills to find on the market is someone who actually understands the finer points of CSS, like why one would use "font-display: swap" in the context of performance, the performance implications of complex CSS on mobile devices, CSS methodology rationale, accessibility implications of using X vs Y, best way of delivering CSS to accelerate the "Start Render" metric, etc.