Who is Josh Comeau's 'CSS for JavaScript Developers' course for?

JS/React developers who use CSS daily but feel parts of their code « work by magic ». The course builds fundamentals to shift from intuition to mastery — especially useful for backend engineers turned fullstack, or frontend engineers wanting to solidify their CSS foundations.

How long does it take to finish the course?

Varies by pace. One to two hours per evening plus weekends is a common schedule. The course mixes articles, videos and exercises, with a workshop at the end of each module. It's not a casual walk — you need to block time.

Is the course still relevant in 2026?

Yes. CSS fundamentals (cascade, layout, z-index, visual model) haven't changed. Modern CSS additions (container queries, has(), nesting) build on top of those fundamentals — without them, you get lost fast.

What does a Senior Engineer take from this course?

Ability to diagnose the root cause of a CSS problem instead of applying a temporary patch — direct technical-debt savings. Ability to teach CSS to peers. Confidence to tackle complex layouts without hacks.

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CSS for JavaScript Developers: Honest Feedback After 4+ Years in Production

Josh Comeau's CSS for JS Developers course reviewed by senior engineer Alexandre Lim, with 8+ years of experience and 4+ years applying knowledge from the course in production for clients. An honest, practical take.

Published 18 May 2026Updated 10 June 20265 min

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