LIDO

This is an excellent creepy short Twine game made for Ectocomp in less than 4 hours.

It features custom CSS styling that nicely represents multiple worlds. You play as someone swimming in a pool that serves as a sort of portal to a darker (or lighter?) world.

There are 3 endings, one of which took me a while to find. The writing is nice and tight, the pacing is good for a short game, and it's visually appealing.

I had to look up the name, as a US resident. Apparently a Lido refers to a public outdoor swimming area, which makes sense since that's what this game is all about.