Sokoban
Push every crate onto a red mark; crates can be pushed but never pulled. Ten levels from easy to tricky, with undo, restart and level select.
Built with
How it was made
Written with Claude Code as a single web page with no libraries; each level was found by pulling crates backwards from the solved position, then solved forwards with a breadth-first search, which also supplies the minimum move count shown when you clear it.