Build a game like Tetris with Claude Code

Build an original browser game in the same genre as Tetris: a falling block puzzle game. Use your own name, characters, art, sound and levels. Only the general mechanics should feel familiar; do not copy Tetris's name, characters, art, music or level layouts.

Version one should have:
- Falling pieces you rotate and move
- Line clears
- Speed that rises with level
- Next piece preview
- Hold piece

The hard part: Rotation rules and collision. Write and test the board logic first.

How to build it:
1. Read this folder first. If it is empty, set up a browser game with Vite, TypeScript and Phaser (or Three.js if it is 3D). Write a short PLAN.md with the game loop, entities, controls and what you are leaving out of version one.
2. Get the core loop playable before anything else: falling pieces you rotate and move. Use simple shapes or free placeholder art until it feels good.
3. Add the rest of the mechanics one at a time, keep game rules in pure functions you can unit test, and make it work with both keyboard and touch.
4. Add a start screen, game over, score and a saved best score in localStorage, plus sound effects you generate or that are free to use.
5. Run it, play it, tune the difficulty, fix what breaks, and finish with a summary and how to deploy it as a static site.

Paste it into Claude Code in an empty folder. It plans first, so read PLAN.md and steer before it starts building.