Very cool!
As an aside, I've learned so many things via games like this. Including vim (via https://vim-adventures.com/), which I now basically can't live without.
Other interesting games for learning CSS,
https://cssgridgarden.com/ (basically Froggy for Grid)
https://cssbattle.dev/ (a platform for doing various challenges, huge community)
https://flukeout.github.io/ (learn about CSS selectors)
https://css-animations.io/ (practice CSS animations)
This is great, I used this years ago when I was learning about flexbox.
There's also https://codepip.com/games/grid-garden/ by the same author that uses the same approach for CSS Grids.
Games seem to be a great way to learn CSS. I'm guessing because it has very natural learning path were you can solve increasingly hard problems that all seem easy because of what you've already learned.
I enjoyed this game to learn CSS selectors a while ago: https://flukeout.github.io/
Guess CSS also has a section about Flexbox, but it focuses more on reading than writing CSS: https://www.guess-css.app/
Fun stuff, got through all the levels but the difficulty only really scales on the last level!
Question from a CSS noob, When would you use Flexbox vs Grid?