There is currently a demo! It's a few months behind at this point, but I've been working on an overhaul of the game and will be putting out a brand new demo once it's in a playable state.
As for in-browser, it will depend on further testing. Screen size / window size is very finicky and rigid with this setup, and especially with mobile formats I'm not sure how well it will handle it. That said, it is something I'm interested in doing.