Note that their goal is to master programming on a new platform, not just to play it in a browser.

That puzzle pack uses GTK too, porting them to Carbon or whatever API Mac OS 9 uses wouldn't be too difficult with some libre SDK targetting OS9.

https://github.com/autc04/Retro68

Also, this guy has a Classic Mac tool sw "runner" a la Wine:

https://github.com/autc04/executor

Forked, that's true, but that's the best Ardi Executor fork by a mile.