Keith Cirkel has been building some interesting and educational web games lately:

Frontend Masters is an online learning platform offering  courses on frontend development technologies such as JavaScript, HTML, CSS, React, and Vue.js. Readers can learn about advanced frontend concepts, best practices, and modern development workflows from industry experts. With video lectures, exercises, and real-world projects, Frontend Masters provides  guidance and expertise for mastering frontend development skills.

Frontend Masters

Keith Cirkel has created three browser-based educational games focused on color perception and CSS knowledge: Hue Shift (match colors by adjusting hue and lightness), What's My ΔE (identify the midpoint between two colors), and CSS or BS? (distinguish real CSS properties from made-up ones).

Keith Cirkel – Frontend Masters Blog

<p>I like how this blurs the line between “learning tool” and “playground.” Feels like the best way to understand CSS isn’t reading docs anymore—it’s building weird, constrained, interactive experiments like these.</p>
