Build a 2D fighting game

the prompt

Build me a playable 2D fighting game in the browser — think Street Fighter distilled: two fighters, a health bar each, real moves and combos. Requirements: 1. A single-screen 2D arena with two fighters facing off, each with a health bar and a round timer. Clean, characterful art (canvas or DOM sprites — animated, not static rectangles). 2. FOUR selectable characters, each visually distinct with at least one unique special move. A simple character-select screen before the fight. 3. Real fighting mechanics: move left/right, jump, crouch, light attack, heavy attack, block, and at least one special/combo (a specific input sequence — e.g. down, forward, punch — that triggers a stronger move). Implement it as a proper state machine so a character can't, say, attack while stunned. 4. Real hit detection: attacks have hitboxes, bodies have hurtboxes, blocking reduces damage, health drains on clean hits, and a round ends in KO or on timer with the higher-health fighter winning. Best-of-3 rounds. 5. Player vs CPU with basic AI (the CPU approaches, attacks in range, blocks sometimes), AND local 2-player on the same keyboard. Show the control scheme on screen. 6. Game feel: hit-pause/screen-shake on heavy hits, a KO announcement, a rematch button. Build it, then QA: play a full best-of-3 against the CPU and a round of 2-player — confirm every move works, combos register, blocking matters, hits register only in range, and rounds/matches end correctly. Fix any broken state. Deploy live to Vercel. DONE when: the deployed game is genuinely playable — four characters, working combos, real hit detection, and a match that plays to a winner. If moves don't register or the state machine breaks (e.g. attacking mid-hitstun), it's not done.

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