Written (mostly) on a red-eye flight to Las Vegas for a trade show. The rest was written while lost in a casino.
Inspired by @agentultra and his laundromat demos as well as @jstimpfle and his Tetris on a plane implementation.
Uses HTML/CSS/JS and no dependancies. The initial app was built at about 30,000 feet with no internet access. I got a little caught up in design details, but I really enjoyed figuring things out without any dependencies or libraries.
You can play a live version of the game here: mastermind.eimaj.dev.