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Cat-Rescue
File size: 34,330 Bytes
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<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>🐱 Cat Rescue — OpenEnv</title>
    <link rel="preconnect" href="https://fonts.googleapis.com" />
    <link href="https://fonts.googleapis.com/css2?family=Inter:wght@400;600;700;900&display=swap" rel="stylesheet" />

    <style>
        /* ── Design Tokens ─────────────────────────────────────────── */
        :root {
            --bg: #0a0a0f;
            --surface: #13131a;
            --surface2: #1c1c28;
            --border: #2a2a3d;
            --accent: #7c6ef5;
            --accent2: #f56ef5;
            --gold: #f5c842;
            --green: #42f5a7;
            --red: #f55a5a;
            --text: #e8e8f0;
            --muted: #7a7a9a;
            --cell-empty: #1e1e2e;
            --cell-hover: #25253a;
            --radius: 14px;
            --radius-sm: 8px;
            --shadow: 0 8px 32px rgba(0, 0, 0, .5);
        }

        /* ── Reset & Base ──────────────────────────────────────────── */
        *,
        *::before,
        *::after {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }

        body {
            font-family: 'Inter', sans-serif;
            background: var(--bg);
            color: var(--text);
            min-height: 100vh;
            overflow-x: hidden;
            background-image:
                radial-gradient(ellipse 80% 60% at 20% -10%, rgba(124, 110, 245, .18) 0%, transparent 60%),
                radial-gradient(ellipse 50% 40% at 80% 110%, rgba(245, 110, 245, .12) 0%, transparent 55%);
        }

        /* ── Layout ────────────────────────────────────────────────── */
        .app {
            max-width: 900px;
            margin: 0 auto;
            padding: 24px 16px 48px;
            display: flex;
            flex-direction: column;
            align-items: center;
            gap: 24px;
        }

        /* ── Header ────────────────────────────────────────────────── */
        header {
            text-align: center;
        }

        header h1 {
            font-size: clamp(1.8rem, 5vw, 2.8rem);
            font-weight: 900;
            background: linear-gradient(135deg, var(--accent), var(--accent2));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            letter-spacing: -1px;
        }

        header p {
            color: var(--muted);
            font-size: .9rem;
            margin-top: 4px;
        }

        /* ── Controls Bar ──────────────────────────────────────────── */
        .controls-bar {
            display: flex;
            align-items: center;
            gap: 12px;
            flex-wrap: wrap;
            justify-content: center;
            width: 100%;
        }

        .level-group {
            display: flex;
            background: var(--surface);
            border: 1px solid var(--border);
            border-radius: 50px;
            padding: 4px;
            gap: 2px;
        }

        .level-btn {
            border: none;
            background: transparent;
            color: var(--muted);
            font-family: 'Inter', sans-serif;
            font-size: .85rem;
            font-weight: 600;
            padding: 6px 18px;
            border-radius: 50px;
            cursor: pointer;
            transition: background .2s, color .2s;
        }

        .level-btn.active {
            background: linear-gradient(135deg, var(--accent), var(--accent2));
            color: #fff;
        }

        .new-game-btn {
            background: linear-gradient(135deg, var(--accent), var(--accent2));
            border: none;
            color: #fff;
            font-family: 'Inter', sans-serif;
            font-size: .9rem;
            font-weight: 700;
            padding: 10px 24px;
            border-radius: 50px;
            cursor: pointer;
            box-shadow: 0 4px 20px rgba(124, 110, 245, .4);
            transition: transform .15s, box-shadow .15s;
        }

        .new-game-btn:hover {
            transform: translateY(-2px);
            box-shadow: 0 6px 28px rgba(124, 110, 245, .55);
        }

        .new-game-btn:active {
            transform: translateY(0);
        }

        /* ── Stats ─────────────────────────────────────────────────── */
        .stats {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 12px;
            width: 100%;
            max-width: 480px;
        }

        .stat-card {
            background: var(--surface);
            border: 1px solid var(--border);
            border-radius: var(--radius);
            padding: 14px 10px;
            text-align: center;
            transition: border-color .3s;
        }

        .stat-card .label {
            font-size: .72rem;
            font-weight: 600;
            text-transform: uppercase;
            letter-spacing: .08em;
            color: var(--muted);
            margin-bottom: 6px;
        }

        .stat-card .value {
            font-size: 1.6rem;
            font-weight: 900;
            line-height: 1;
        }

        #stat-score .value {
            color: var(--gold);
        }

        #stat-steps .value {
            color: var(--accent);
        }

        #stat-cats .value {
            color: var(--green);
        }

        /* bump animation when a value changes */
        @keyframes bump {
            0% {
                transform: scale(1);
            }

            40% {
                transform: scale(1.35);
            }

            100% {
                transform: scale(1);
            }
        }

        .bump {
            animation: bump .35s ease;
        }

        /* ── Game Grid ─────────────────────────────────────────────── */
        .grid-wrapper {
            position: relative;
            background: var(--surface);
            border: 1px solid var(--border);
            border-radius: var(--radius);
            padding: 16px;
            box-shadow: var(--shadow);
        }

        #game-grid {
            display: grid;
            gap: 5px;
        }

        .cell {
            width: clamp(44px, 10vw, 72px);
            height: clamp(44px, 10vw, 72px);
            border-radius: var(--radius-sm);
            background: var(--cell-empty);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: clamp(1.4rem, 4vw, 2.2rem);
            transition: background .2s, transform .15s;
            user-select: none;
            position: relative;
            overflow: hidden;
        }

        .cell.wall {
            background: #141420;
            box-shadow: inset 0 0 12px rgba(0, 0, 0, .6);
        }

        .cell.agent {
            background: rgba(124, 110, 245, .18);
            border: 2px solid rgba(124, 110, 245, .5);
        }

        .cell.cat {
            background: rgba(245, 200, 66, .10);
            border: 2px solid rgba(245, 200, 66, .35);
        }

        .cell.obstacle {
            background: rgba(245, 90, 90, .12);
            border: 2px solid rgba(245, 90, 90, .4);
        }

        /* Agent "slide-in" for new position */
        @keyframes slidein {
            from {
                transform: scale(.5);
                opacity: .4;
            }

            to {
                transform: scale(1);
                opacity: 1;
            }
        }

        .cell.agent {
            animation: slidein .22s ease;
        }

        /* Cat pulse */
        @keyframes catpulse {

            0%,
            100% {
                transform: scale(1);
            }

            50% {
                transform: scale(1.15);
            }
        }

        .cell.cat {
            animation: catpulse 1.8s ease-in-out infinite;
        }

        /* Wall shake on collision */
        @keyframes shake {

            0%,
            100% {
                transform: translateX(0);
            }

            25% {
                transform: translateX(-5px);
            }

            75% {
                transform: translateX(5px);
            }
        }

        .shake {
            animation: shake .25s ease !important;
        }

        /* ── Arrow Controls ────────────────────────────────────────── */
        .arrow-pad {
            display: grid;
            grid-template-areas:
                ".    up   ."
                "left down right";
            gap: 8px;
        }

        .arrow-btn {
            width: 56px;
            height: 56px;
            background: var(--surface2);
            border: 1px solid var(--border);
            border-radius: var(--radius-sm);
            color: var(--text);
            font-size: 1.4rem;
            cursor: pointer;
            display: flex;
            align-items: center;
            justify-content: center;
            transition: background .15s, transform .1s, border-color .15s;
            touch-action: manipulation;
        }

        .arrow-btn:hover {
            background: var(--surface);
            border-color: var(--accent);
        }

        .arrow-btn:active {
            transform: scale(.9);
            background: rgba(124, 110, 245, .2);
        }

        [data-dir="0"] {
            grid-area: up;
        }

        [data-dir="1"] {
            grid-area: down;
        }

        [data-dir="2"] {
            grid-area: left;
        }

        [data-dir="3"] {
            grid-area: right;
        }

        /* ── Overlay ───────────────────────────────────────────────── */
        .overlay {
            position: absolute;
            inset: 0;
            border-radius: var(--radius);
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            gap: 16px;
            backdrop-filter: blur(6px);
            opacity: 0;
            pointer-events: none;
            transition: opacity .4s;
            z-index: 10;
        }

        .overlay.show {
            opacity: 1;
            pointer-events: all;
        }

        .overlay-win {
            background: rgba(10, 10, 15, .85);
        }

        .overlay-lose {
            background: rgba(10, 10, 15, .85);
        }

        .overlay h2 {
            font-size: clamp(1.6rem, 5vw, 2.4rem);
            font-weight: 900;
            text-align: center;
        }

        .overlay .sub {
            font-size: .95rem;
            color: var(--muted);
            text-align: center;
        }

        .overlay-btn {
            background: linear-gradient(135deg, var(--accent), var(--accent2));
            border: none;
            color: #fff;
            font-family: 'Inter', sans-serif;
            font-weight: 700;
            font-size: 1rem;
            padding: 12px 32px;
            border-radius: 50px;
            cursor: pointer;
            box-shadow: 0 4px 20px rgba(124, 110, 245, .4);
            transition: transform .15s;
        }

        .overlay-btn:hover {
            transform: translateY(-2px);
        }

        /* ── Confetti ──────────────────────────────────────────────── */
        #confetti-canvas {
            position: fixed;
            inset: 0;
            pointer-events: none;
            z-index: 999;
        }

        /* ── Status toast ──────────────────────────────────────────── */
        #toast {
            position: fixed;
            bottom: 28px;
            left: 50%;
            transform: translateX(-50%) translateY(80px);
            background: var(--surface2);
            border: 1px solid var(--border);
            border-radius: 50px;
            padding: 10px 24px;
            font-size: .9rem;
            font-weight: 600;
            color: var(--text);
            box-shadow: var(--shadow);
            transition: transform .35s cubic-bezier(.34, 1.56, .64, 1);
            z-index: 200;
            white-space: nowrap;
        }

        #toast.show {
            transform: translateX(-50%) translateY(0);
        }

        /* ── Score flash ───────────────────────────────────────────── */
        .score-flash {
            position: fixed;
            font-weight: 900;
            font-size: 1.6rem;
            pointer-events: none;
            z-index: 300;
            animation: floatup .9s ease forwards;
        }

        @keyframes floatup {
            0% {
                opacity: 1;
                transform: translateY(0) scale(1);
            }

            100% {
                opacity: 0;
                transform: translateY(-70px) scale(1.3);
            }
        }

        /* ── CORS error notice ─────────────────────────────────────── */
        #cors-notice {
            display: none;
            background: rgba(245, 90, 90, .12);
            border: 1px solid rgba(245, 90, 90, .4);
            border-radius: var(--radius);
            padding: 16px 20px;
            font-size: .88rem;
            color: #f59090;
            text-align: center;
            width: 100%;
            max-width: 520px;
        }

        /* ── Legend ────────────────────────────────────────────────── */
        .legend {
            display: flex;
            gap: 20px;
            flex-wrap: wrap;
            justify-content: center;
            font-size: .82rem;
            color: var(--muted);
        }

        .legend span {
            display: flex;
            align-items: center;
            gap: 5px;
        }

        /* ── Loading spinner ───────────────────────────────────────── */
        .spinner {
            width: 32px;
            height: 32px;
            border: 3px solid var(--border);
            border-top-color: var(--accent);
            border-radius: 50%;
            animation: spin .7s linear infinite;
        }

        @keyframes spin {
            to {
                transform: rotate(360deg);
            }
        }

        /* ── Responsive ────────────────────────────────────────────── */
        @media (max-width: 520px) {
            .stats {
                max-width: 100%;
            }

            .arrow-btn {
                width: 50px;
                height: 50px;
                font-size: 1.2rem;
            }
        }
    </style>
</head>

<body>

    <canvas id="confetti-canvas"></canvas>
    <div id="toast"></div>

    <div class="app">
        <!-- Header -->
        <header>
            <h1>🐱 Cat Rescue</h1>
            <p>Navigate the grid and rescue every cat!</p>
        </header>

        <!-- Controls bar -->
        <div class="controls-bar">
            <div class="level-group" id="level-group">
                <button class="level-btn active" data-level="1">Level 1</button>
                <button class="level-btn" data-level="2">Level 2</button>
                <button class="level-btn" data-level="3">Level 3</button>
            </div>
            <button class="new-game-btn" id="new-game-btn">🔄 New Game</button>
        </div>

        <!-- CORS error -->
        <div id="cors-notice">
            ⚠️ Could not reach the game server. This may be a CORS or network issue.
            Make sure the backend at <strong>https://vizxal-cat-rescue.hf.space</strong> is running,
            then refresh the page.
        </div>

        <!-- Stats -->
        <div class="stats">
            <div class="stat-card" id="stat-score">
                <div class="label">Score</div>
                <div class="value" id="score-val">0.0</div>
            </div>
            <div class="stat-card" id="stat-steps">
                <div class="label">Steps</div>
                <div class="value" id="steps-val">0</div>
            </div>
            <div class="stat-card" id="stat-cats">
                <div class="label">Rescued</div>
                <div class="value" id="cats-val">0</div>
            </div>
        </div>

        <!-- Grid -->
        <div class="grid-wrapper" id="grid-wrapper">
            <div id="game-grid">
                <div class="spinner"></div>
            </div>

            <!-- Win overlay -->
            <div class="overlay overlay-win" id="win-overlay">
                <div style="font-size:4rem">🎉</div>
                <h2 style="color:var(--green)">All Cats Rescued!</h2>
                <p class="sub" id="win-msg"></p>
                <button class="overlay-btn" onclick="startNewGame()">Play Again</button>
            </div>

            <!-- Game-over overlay -->
            <div class="overlay overlay-lose" id="lose-overlay">
                <div style="font-size:4rem">😿</div>
                <h2 style="color:var(--red)">Out of Steps!</h2>
                <p class="sub" id="lose-msg"></p>
                <button class="overlay-btn" onclick="startNewGame()">Try Again</button>
            </div>
        </div>

        <!-- Arrow pad -->
        <div class="arrow-pad">
            <button class="arrow-btn" data-dir="0" aria-label="Up">⬆️</button>
            <button class="arrow-btn" data-dir="2" aria-label="Left">⬅️</button>
            <button class="arrow-btn" data-dir="1" aria-label="Down">⬇️</button>
            <button class="arrow-btn" data-dir="3" aria-label="Right">➡️</button>
        </div>

        <!-- Legend -->
        <div class="legend">
            <span>😸 Agent</span>
            <span>🐱 Cat</span>
            <span>🧱 Wall</span>
            <span>💥 Obstacle</span>
            <span>⬜ Empty</span>
        </div>
    </div>

    <script>
        /* ─── Config ─────────────────────────────────────────────────────────────── */
        const API = 'https://vizxal-cat-rescue.hf.space';

        // Cell type constants (must match environment.py)
        const EMPTY = 0, WALL = 1, CAT = 2, AGENT = 3, OBSTACLE = 4;

        /* ─── State ──────────────────────────────────────────────────────────────── */
        let currentObs = null;   // latest observation dict from the server
        let currentLevel = 1;
        let totalScore = 0;
        let busy = false;  // prevent double-sends while fetch is in-flight
        let agentCell = null;   // DOM reference to the agent's current cell

        /* ─── API helpers ────────────────────────────────────────────────────────── */
        async function apiFetch(path, opts = {}) {
            const res = await fetch(API + path, {
                headers: { 'Content-Type': 'application/json' },
                ...opts,
            });
            if (!res.ok) throw new Error(`HTTP ${res.status}`);
            return res.json();
        }

        async function apiReset(level, seed) {
            const data = await apiFetch('/reset', {
                method: 'POST',
                body: JSON.stringify({ level, max_steps: 200, seed: seed ?? null }),
            });
            return data.observation;
        }

        async function apiStep(action) {
            const data = await apiFetch('/step', {
                method: 'POST',
                body: JSON.stringify({ action }),
            });
            return data; // { observation, reward, done, info }
        }

        /* ─── Game lifecycle ─────────────────────────────────────────────────────── */
        async function startNewGame() {
            busy = true;
            hideOverlays();
            totalScore = 0;

            // Pick a random seed so each game is different
            const seed = Math.floor(Math.random() * 99999);

            try {
                currentObs = await apiReset(currentLevel, seed);
                updateStats(0, 0, 0);
                renderGrid(currentObs.grid);
                document.getElementById('cors-notice').style.display = 'none';
            } catch (e) {
                showCorsError();
            } finally {
                busy = false;
            }
        }

        async function takeAction(action) {
            if (busy || !currentObs || currentObs.done) return;
            busy = true;

            try {
                const result = await apiStep(action);
                const { observation: obs, reward, done, info } = result;
                currentObs = obs;

                // Accumulate score
                totalScore = Math.round((totalScore + reward) * 100) / 100;

                // Animate stat bump when values change
                if (info.event === 'cat_rescued' || info.event === 'all_rescued') {
                    spawnScoreFlash('+1.0 🐱');
                    bumpStat('stat-cats');
                }
                if (info.event === 'hit_wall' || info.event === 'hit_obstacle') {
                    shakeGrid();
                }

                updateStats(totalScore, obs.step_count, obs.cats_rescued);
                renderGrid(obs.grid);

                if (info.event === 'all_rescued') {
                    setTimeout(() => showWin(obs), 400);
                } else if (done) {
                    setTimeout(() => showLose(obs), 400);
                }
            } catch (e) {
                showToast('⚠️ Server error – try refreshing');
            } finally {
                busy = false;
            }
        }

        /* ─── Grid renderer ──────────────────────────────────────────────────────── */
        function renderGrid(grid) {
            const rows = grid.length;
            const cols = grid[0].length;
            const container = document.getElementById('game-grid');

            container.style.gridTemplateColumns = `repeat(${cols}, 1fr)`;

            // Re-use existing cells if the grid dimensions haven't changed
            const existingCells = container.querySelectorAll('.cell');
            const totalCells = rows * cols;

            if (existingCells.length !== totalCells) {
                container.innerHTML = '';
                for (let i = 0; i < totalCells; i++) {
                    const cell = document.createElement('div');
                    cell.className = 'cell';
                    container.appendChild(cell);
                }
            }

            const cells = container.querySelectorAll('.cell');
            for (let r = 0; r < rows; r++) {
                for (let c = 0; c < cols; c++) {
                    const idx = r * cols + c;
                    const val = grid[r][c];
                    const cell = cells[idx];

                    // Reset classes
                    cell.className = 'cell';
                    cell.textContent = '';

                    switch (val) {
                        case WALL:
                            cell.classList.add('wall');
                            cell.textContent = '🧱';
                            break;
                        case CAT:
                            cell.classList.add('cat');
                            cell.textContent = '🐱';
                            break;
                        case AGENT:
                            cell.classList.add('agent');
                            cell.textContent = '😸';
                            agentCell = cell;
                            break;
                        case OBSTACLE:
                            cell.classList.add('obstacle');
                            cell.textContent = '💥';
                            break;
                        default:
                            // EMPTY — just a styled background
                            break;
                    }
                }
            }
        }

        /* ─── Stats updater ──────────────────────────────────────────────────────── */
        function updateStats(score, steps, rescued) {
            setText('score-val', score.toFixed(1));
            setText('steps-val', steps);
            setText('cats-val', rescued);
        }

        function setText(id, val) {
            const el = document.getElementById(id);
            if (el.textContent !== String(val)) {
                el.textContent = val;
                el.classList.remove('bump');
                void el.offsetWidth; // force reflow
                el.classList.add('bump');
            }
        }

        /* ─── Overlays ───────────────────────────────────────────────────────────── */
        function showWin(obs) {
            document.getElementById('win-msg').textContent =
                `You rescued all ${obs.cats_rescued} cat${obs.cats_rescued !== 1 ? 's' : ''} in ${obs.step_count} steps! Score: ${totalScore.toFixed(1)}`;
            document.getElementById('win-overlay').classList.add('show');
            launchConfetti();
        }

        function showLose(obs) {
            document.getElementById('lose-msg').textContent =
                `You rescued ${obs.cats_rescued} of ${obs.cats_rescued + (obs.cats_remaining ?? 0)} cats. Score: ${totalScore.toFixed(1)}`;
            document.getElementById('lose-overlay').classList.add('show');
        }

        function hideOverlays() {
            document.getElementById('win-overlay').classList.remove('show');
            document.getElementById('lose-overlay').classList.remove('show');
        }

        /* ─── Visual effects ─────────────────────────────────────────────────────── */
        function shakeGrid() {
            const wrapper = document.getElementById('grid-wrapper');
            wrapper.classList.remove('shake');
            void wrapper.offsetWidth;
            wrapper.classList.add('shake');
            setTimeout(() => wrapper.classList.remove('shake'), 260);
        }

        function bumpStat(id) {
            const el = document.getElementById(id);
            el.classList.remove('bump');
            void el.offsetWidth;
            el.classList.add('bump');
        }

        function spawnScoreFlash(text) {
            const el = document.createElement('div');
            el.className = 'score-flash';
            el.textContent = text;
            el.style.cssText = `top:${window.innerHeight * .4}px;left:${window.innerWidth / 2 - 40}px;color:#42f5a7`;
            document.body.appendChild(el);
            el.addEventListener('animationend', () => el.remove());
        }

        /* ─── Toast notification ─────────────────────────────────────────────────── */
        let toastTimer;
        function showToast(msg) {
            const t = document.getElementById('toast');
            t.textContent = msg;
            t.classList.add('show');
            clearTimeout(toastTimer);
            toastTimer = setTimeout(() => t.classList.remove('show'), 2800);
        }

        /* ─── CORS / network error ───────────────────────────────────────────────── */
        function showCorsError() {
            document.getElementById('cors-notice').style.display = 'block';
            document.getElementById('game-grid').innerHTML = '<div style="color:var(--muted);font-size:.9rem;padding:24px">⚠️ Could not connect to server</div>';
        }

        /* ─── Level selector ─────────────────────────────────────────────────────── */
        document.getElementById('level-group').addEventListener('click', e => {
            const btn = e.target.closest('.level-btn');
            if (!btn) return;
            document.querySelectorAll('.level-btn').forEach(b => b.classList.remove('active'));
            btn.classList.add('active');
            currentLevel = Number(btn.dataset.level);
            startNewGame();
        });

        /* ─── New Game button ────────────────────────────────────────────────────── */
        document.getElementById('new-game-btn').addEventListener('click', startNewGame);

        /* ─── Arrow pad ──────────────────────────────────────────────────────────── */
        document.querySelectorAll('.arrow-btn').forEach(btn => {
            btn.addEventListener('click', () => takeAction(Number(btn.dataset.dir)));
            // Touch hold for continuous movement
            let holdInterval;
            btn.addEventListener('pointerdown', () => {
                holdInterval = setInterval(() => takeAction(Number(btn.dataset.dir)), 200);
            });
            btn.addEventListener('pointerup', () => clearInterval(holdInterval));
            btn.addEventListener('pointerleave', () => clearInterval(holdInterval));
        });

        /* ─── Keyboard ───────────────────────────────────────────────────────────── */
        document.addEventListener('keydown', e => {
            const map = {
                ArrowUp: 0, ArrowDown: 1, ArrowLeft: 2, ArrowRight: 3,
                w: 0, s: 1, a: 2, d: 3
            };
            if (e.key in map) {
                e.preventDefault();
                takeAction(map[e.key]);
            }
        });

        /* ─── Confetti ───────────────────────────────────────────────────────────── */
        function launchConfetti() {
            const canvas = document.getElementById('confetti-canvas');
            const ctx = canvas.getContext('2d');
            canvas.width = window.innerWidth;
            canvas.height = window.innerHeight;

            const COLORS = ['#7c6ef5', '#f56ef5', '#f5c842', '#42f5a7', '#f55a5a', '#5af5f5'];
            const pieces = Array.from({ length: 140 }, () => ({
                x: Math.random() * canvas.width,
                y: Math.random() * -canvas.height,
                r: Math.random() * 7 + 3,
                d: Math.random() * 140,
                color: COLORS[Math.floor(Math.random() * COLORS.length)],
                tilt: Math.random() * 10 - 10,
                tiltSpeed: Math.random() * .1 + .05,
                speed: Math.random() * 3 + 1.5,
            }));

            let angle = 0;
            let frame;
            let startTime = Date.now();

            function draw() {
                ctx.clearRect(0, 0, canvas.width, canvas.height);
                angle += .01;
                pieces.forEach(p => {
                    p.y += p.speed;
                    p.tilt += p.tiltSpeed;
                    if (p.y > canvas.height) { p.y = -10; p.x = Math.random() * canvas.width; }
                    ctx.beginPath();
                    ctx.lineWidth = p.r;
                    ctx.strokeStyle = p.color;
                    ctx.moveTo(p.x + p.tilt + p.r / 2, p.y);
                    ctx.lineTo(p.x + p.tilt, p.y + p.tilt + p.r / 2);
                    ctx.stroke();
                });
                if (Date.now() - startTime < 4000) {
                    frame = requestAnimationFrame(draw);
                } else {
                    ctx.clearRect(0, 0, canvas.width, canvas.height);
                }
            }
            cancelAnimationFrame(frame);
            draw();
        }

        /* ─── Boot ───────────────────────────────────────────────────────────────── */
        startNewGame();
    </script>
</body>

</html>