I'm probably showing my age, but I'm just at awe what is possible in a browser in this day and age. Well done, OP. I'd love a hashed out, full length version of this, but with the same vector graphics.
There were things, like Epic Citadel, a full port of Unreal Engine to the browser (using asm.js, a technique of compiling assembly to Javascript) a decade ago:
https://www.youtube.com/watch?v=l9KRBuVBjVo
And yeah even that somehow feels futuristic today.