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    <meta name="description" content="NumberFlow Pro - The ultimate 15-puzzle sliding tile game. Challenge your mind with smooth animations and responsive design. Play for free on any device!">
    <meta name="keywords" content="15 puzzle, sliding puzzle, number puzzle, brain game, logic game, tile puzzle, NumberFlow Pro">
    <meta name="author" content="NumberFlow Pro Game">
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    <meta property="og:title" content="NumberFlow Pro - Ultimate 15-Puzzle Challenge">
    <meta property="og:description" content="Challenge your mind with NumberFlow Pro, the smoothest 15-puzzle game experience. Play for free!">
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    <title>NumberFlow Pro - The Ultimate 15-Puzzle Challenge | Play Free Online</title>
    
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    <!-- Tailwind CSS -->
    <link href="https://cdn.jsdelivr.net/npm/tailwindcss@2.2.19/dist/tailwind.min.css" rel="stylesheet">
    
    <!-- Font Awesome -->
    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/@fortawesome/fontawesome-free@6.4.0/css/all.min.css">
    
    <!-- Google Fonts -->
    <link href="https://fonts.googleapis.com/css2?family=Poppins:wght@400;600;700&display=swap" rel="stylesheet">
    
    <style>
        * {
            box-sizing: border-box;
        }
        
        body {
            font-family: 'Poppins', sans-serif;
            margin: 0;
            padding: 0;
            background-color: #ffffff;
            overflow-x: hidden;
        }
        
        /* Custom color scheme - Dark Green and Yellow */
        :root {
            --primary-green: #2d5a27;
            --light-green: #4a7c59;
            --primary-yellow: #f4d03f;
            --light-yellow: #f7dc6f;
            --bg-white: #ffffff;
            --text-dark: #2c3e50;
            --shadow: rgba(0, 0, 0, 0.1);
        }
        
        /* Game Container */
        .game-container {
            max-width: 600px;
            margin: 0 auto;
            padding: 20px;
        }
        
        /* Game Board */
        .game-board {
            width: 100%;
            max-width: 400px;
            aspect-ratio: 1;
            margin: 0 auto;
            background-color: var(--primary-green);
            border-radius: 15px;
            padding: 10px;
            box-shadow: 0 8px 25px var(--shadow);
            position: relative;
        }
        
        /* Game Grid */
        .puzzle-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            grid-template-rows: repeat(4, 1fr);
            gap: 8px;
            width: 100%;
            height: 100%;
        }
        
        /* Game Tiles */
        .tile {
            display: flex;
            align-items: center;
            justify-content: center;
            background-color: var(--primary-yellow);
            border-radius: 8px;
            font-size: 1.5rem;
            font-weight: 700;
            color: var(--text-dark);
            cursor: pointer;
            transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
            border: 2px solid var(--light-yellow);
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
            user-select: none;
        }
        
        .tile:hover {
            background-color: var(--light-yellow);
            transform: scale(1.05);
            box-shadow: 0 6px 20px rgba(0, 0, 0, 0.2);
        }
        
        .tile.empty {
            background-color: transparent;
            border: 2px dashed var(--light-green);
            cursor: default;
            box-shadow: none;
        }
        
        .tile.empty:hover {
            transform: none;
            background-color: transparent;
        }
        
        /* Control Buttons */
        .control-btn {
            background-color: var(--light-green);
            color: white;
            border: none;
            padding: 12px 24px;
            border-radius: 8px;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s ease;
            box-shadow: 0 4px 12px var(--shadow);
        }
        
        .control-btn:hover {
            background-color: var(--primary-green);
            transform: translateY(-2px);
            box-shadow: 0 6px 20px var(--shadow);
        }
        
        /* Stats Display */
        .stats {
            background-color: var(--light-yellow);
            color: var(--text-dark);
            padding: 15px;
            border-radius: 10px;
            font-weight: 600;
            text-align: center;
            box-shadow: 0 4px 12px var(--shadow);
        }
        
        /* Game Ads Spaces */
        .game-ads {
            width: 120px;
            background-color: #f8f9fa;
            border: 2px dashed #dee2e6;
            border-radius: 8px;
            position: fixed;
            padding: 10px;
            display: flex;
            flex-direction: column;
            align-items: center;
            gap: 15px;
        }
        
        .game-ads-left {
            left: 10px;
            top: 70px;
        }
        
        .game-ads-right {
            right: 10px;
            top: 70px;
        }
        
        .game-ad-image {
            width: 100px;
            height: 100px;
            object-fit: cover;
            border-radius: 8px;
            transition: transform 0.3s ease;
        }
        
        .game-ad-image:hover {
            transform: scale(1.05);
        }
        
        /* Victory Animation */
        @keyframes victory {
            0% { transform: scale(1) rotate(0deg); }
            50% { transform: scale(1.1) rotate(5deg); }
            100% { transform: scale(1) rotate(0deg); }
        }
        
        .victory-tile {
            animation: victory 0.6s ease-in-out;
            background-color: var(--light-yellow) !important;
        }

        /* Victory Message */
        .victory-message {
            display: none;
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background-color: rgba(0, 0, 0, 0.8);
            z-index: 1000;
            justify-content: center;
            align-items: center;
            flex-direction: column;
            color: white;
            text-align: center;
        }

        .victory-content {
            background-color: var(--primary-green);
            padding: 30px;
            border-radius: 15px;
            max-width: 80%;
            box-shadow: 0 10px 25px rgba(0, 0, 0, 0.3);
        }

        .victory-content h2 {
            font-size: 2.5rem;
            margin-bottom: 20px;
            color: var(--primary-yellow);
        }

        .victory-content p {
            font-size: 1.2rem;
            margin-bottom: 20px;
        }

        .victory-btn {
            background-color: var(--primary-yellow);
            color: var(--text-dark);
            border: none;
            padding: 12px 24px;
            border-radius: 8px;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s ease;
            box-shadow: 0 4px 12px var(--shadow);
        }

        .victory-btn:hover {
            background-color: var(--light-yellow);
            transform: translateY(-2px);
        }

        /* Title Animation */
        @keyframes titleGlow {
            0% { text-shadow: 0 0 5px rgba(244, 208, 63, 0.5); }
            50% { text-shadow: 0 0 15px rgba(244, 208, 63, 0.8); }
            100% { text-shadow: 0 0 5px rgba(244, 208, 63, 0.5); }
        }

        .game-title {
            animation: titleGlow 3s infinite;
            position: relative;
            display: inline-block;
        }

        .game-title::after {
            content: "";
            position: absolute;
            bottom: -5px;
            left: 0;
            width: 100%;
            height: 3px;
            background: linear-gradient(90deg, transparent, var(--primary-yellow), transparent);
            border-radius: 3px;
        }
        
        /* Angel Mascot */
        .angel-mascot-container {
            position: fixed;
            top: 18px;
            left: 10px;
            z-index: 100;
        }
        
        /* Responsive Design */
        @media (max-width: 768px) {
            .game-container {
                padding: 10px;
            }
            
            .game-ads {
                display: none;
            }
            
            .tile {
                font-size: 1.2rem;
            }
            
            .game-board {
                max-width: 350px;
            }

            .victory-content h2 {
                font-size: 2rem;
            }

            .victory-content p {
                font-size: 1rem;
            }
        }
        
        @media (max-width: 480px) {
            .tile {
                font-size: 1rem;
            }
            
            .game-board {
                max-width: 300px;
                padding: 8px;
            }
            
            .puzzle-grid {
                gap: 6px;
            }

            .victory-content {
                padding: 20px;
            }

            .victory-content h2 {
                font-size: 1.5rem;
            }
        }
    </style>
</head>
<body>
    <!-- Angel Mascot with Home Link -->
    <a href="../index.html" class="angel-mascot-container">
        <div class="angel-face" id="angelFace" style="
            display: inline-block;
            width: 40px;
            height: 40px;
            position: relative;
            vertical-align: middle;
            margin: 0 4px;
            border-radius: 50%;
            background: linear-gradient(145deg, #ffecd1, #ffb88c);
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15), inset 0 2px 4px rgba(255, 255, 255, 0.3);
            transition: all 0.3s ease;
            overflow: visible;
        ">
            <!-- Hair -->
            <div style="
                content: '';
                position: absolute;
                top: -8px;
                left: -2px;
                right: -2px;
                height: 25px;
                background: linear-gradient(145deg, #d4af37, #ffd700);
                border-radius: 50% 50% 45% 45%;
                z-index: 2;
                box-shadow: 0 2px 6px rgba(0, 0, 0, 0.1);
            "></div>
            
            <!-- Halo -->
            <div style="
                content: '';
                position: absolute;
                top: -15px;
                left: 50%;
                transform: translateX(-50%);
                width: 35px;
                height: 6px;
                border: 2px solid #ffd700;
                border-radius: 50%;
                background: transparent;
                box-shadow: 0 0 8px rgba(255, 215, 0, 0.4);
                z-index: 3;
            "></div>
            
            <!-- Left Eye -->
            <div class="left-eye" style="
                position: absolute;
                width: 8px;
                height: 8px;
                background: #fff;
                border-radius: 50%;
                top: 45%;
                left: 28%;
                border: 1px solid #e0e0e0;
                box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.1);
                z-index: 1;
            ">
                <div class="left-pupil" id="leftPupil" style="
                    position: absolute;
                    width: 4px;
                    height: 4px;
                    background: #2563eb;
                    border-radius: 50%;
                    top: 50%;
                    left: 50%;
                    transform: translate(-50%, -50%);
                    transition: all 0.1s ease;
                    z-index: 1;
                ">
                    <div style="
                        content: '';
                        position: absolute;
                        width: 1.5px;
                        height: 1.5px;
                        background: white;
                        border-radius: 50%;
                        top: 20%;
                        left: 30%;
                    "></div>
                </div>
            </div>
            
            <!-- Right Eye -->
            <div class="right-eye" style="
                position: absolute;
                width: 8px;
                height: 8px;
                background: #fff;
                border-radius: 50%;
                top: 45%;
                left: 64%;
                border: 1px solid #e0e0e0;
                box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.1);
                z-index: 1;
            ">
                <div class="right-pupil" id="rightPupil" style="
                    position: absolute;
                    width: 4px;
                    height: 4px;
                    background: #2563eb;
                    border-radius: 50%;
                    top: 50%;
                    left: 50%;
                    transform: translate(-50%, -50%);
                    transition: all 0.1s ease;
                    z-index: 1;
                ">
                    <div style="
                        content: '';
                        position: absolute;
                        width: 1.5px;
                        height: 1.5px;
                        background: white;
                        border-radius: 50%;
                        top: 20%;
                        left: 30%;
                    "></div>
                </div>
            </div>
            
            <!-- Nose -->
            <div class="nose" style="
                position: absolute;
                top: 55%;
                left: 50%;
                transform: translateX(-50%);
                width: 2px;
                height: 3px;
                background: #ffb88c;
                border-radius: 0 0 50% 50%;
                z-index: 1;
            "></div>
            
            <!-- Smile -->
            <div class="smile" style="
                position: absolute;
                top: 65%;
                left: 50%;
                transform: translateX(-50%);
                width: 12px;
                height: 6px;
                border: 1.5px solid #ff6b8a;
                border-top: none;
                border-radius: 0 0 12px 12px;
                background: transparent;
                z-index: 1;
            "></div>
            
            <!-- Cheeks -->
            <div class="left-cheek" style="
                position: absolute;
                width: 6px;
                height: 4px;
                background: rgba(255, 182, 193, 0.6);
                border-radius: 50%;
                top: 58%;
                left: 15%;
                z-index: 1;
            "></div>
            <div class="right-cheek" style="
                position: absolute;
                width: 6px;
                height: 4px;
                background: rgba(255, 182, 193, 0.6);
                border-radius: 50%;
                top: 58%;
                right: 15%;
                z-index: 1;
            "></div>
        </div>
    </a>

    <!-- Left Game Ads Box -->
    <div class="game-ads game-ads-left">
        <a href="../balloonblast/balloonblast.html">
            <img src="../balloonblast/balloonblast.png" alt="Balloon Blast" class="game-ad-image">
        </a>
        <a href="../memorychallenge/memchal.html">
            <img src="../memorychallenge/memorychallenge.png" alt="Memory Challenge" class="game-ad-image">
        </a>
        <a href="../mergetiles/mergetiles.html">
            <img src="../mergetiles/mergetiles.png" alt="Merge Tiles" class="game-ad-image">
        </a>
        <a href="../multihorn/multihorn.html">
            <img src="../multihorn/multihorn.png" alt="Multi Horn" class="game-ad-image">
        </a>
        <a href="../zenbreath/zenbreath.html">
            <img src="../zenbreath/zenbreath.png" alt="Zen Breath" class="game-ad-image">
        </a>
    </div>

    <!-- Right Game Ads Box -->
    <div class="game-ads game-ads-right">
        <a href="../numberflow/numberflowpro.html">
            <img src="../numberflow/numberflowpro.png" alt="NumberFlow Pro" class="game-ad-image">
        </a>
        <a href="../quickmath/quickmath.html">
            <img src="../quickmath/quickmath.png" alt="Quick Math" class="game-ad-image">
        </a>
        <a href="../aquarium/aquarium.html">
            <img src="../aquarium/aquarium.png" alt="Aquarium" class="game-ad-image">
        </a>
        <a href="../nexusgrid/nexusgrid.html">
            <img src="../nexusgrid/nexusgrid.png" alt="Nexus Grid" class="game-ad-image">
        </a>
        <a href="../interactivelights/interactivelights.html">
            <img src="../interactivelights/interactivelights.png" alt="Interactive Lights" class="game-ad-image">
        </a>
    </div>

    <!-- Victory Message (Hidden by default) -->
    <div class="victory-message" id="victoryMessage">
        <div class="victory-content">
            <h2>🎉 You Won! 🎉</h2>
            <p id="victoryStats">Completed in <span id="victoryMoves">0</span> moves and <span id="victoryTime">00:00</span>!</p>
            <button class="victory-btn" id="victoryReturnBtn">
                <i class="fas fa-redo mr-2"></i>Play Again
            </button>
        </div>
    </div>

    <!-- Main Game Container -->
    <div class="min-h-screen flex items-center justify-center py-4">
        <div class="game-container">
            <!-- Header -->
            <header class="text-center mb-6">
                <h1 class="text-4xl font-bold mb-2 text-gray-800 game-title">
                    <i class="fas fa-puzzle-piece text-yellow-500 mr-2"></i>
                    NumberFlow Pro
                </h1>
                <p class="text-gray-600">The Ultimate 15-Puzzle Challenge</p>
            </header>
            
            <!-- Game Stats -->
            <div class="flex justify-center gap-4 mb-6">
                <div class="stats">
                    <i class="fas fa-footsteps mr-2"></i>
                    <span>Moves: </span>
                    <span id="moveCount">0</span>
                </div>
                <div class="stats">
                    <i class="fas fa-clock mr-2"></i>
                    <span>Time: </span>
                    <span id="timeDisplay">00:00</span>
                </div>
            </div>
            
            <!-- Game Controls -->
            <div class="flex justify-center gap-4 mb-6">
                <button id="startBtn" class="control-btn">
                    <i class="fas fa-play mr-2"></i>Start Game
                </button>
                <button id="resetBtn" class="control-btn">
                    <i class="fas fa-redo mr-2"></i>Reset
                </button>
            </div>
            
            <!-- Game Board -->
            <div class="game-board">
                <div class="puzzle-grid" id="puzzleGrid">
                    <!-- Tiles will be generated by JavaScript -->
                </div>
            </div>
            
            <!-- Instructions -->
            <div class="mt-6 text-center">
                <h3 class="text-lg font-semibold mb-2 text-gray-800">How to Play</h3>
                <p class="text-gray-600 text-sm">
                    <i class="fas fa-mouse-pointer mr-1"></i> Click tiles to move them into the empty space<br>
                    <i class="fas fa-keyboard mr-1"></i> Use arrow keys to move tiles<br>
                    <i class="fas fa-trophy mr-1"></i> Arrange numbers 1-15 in order to win!
                </p>
            </div>
        </div>
    </div>

    <script>
        /**
         * NumberFlow Pro - 15-Puzzle Game
         * A modern, responsive implementation of the classic sliding puzzle
         */
        
        class NumberFlowPro {
            constructor() {
                // Game state variables
                this.board = [];           // Current board configuration
                this.emptyPos = {x: 3, y: 3}; // Position of empty tile
                this.moves = 0;           // Move counter
                this.gameStarted = false; // Game state flag
                this.gameWon = false;     // Victory state flag
                this.startTime = null;    // Game start timestamp
                this.timerInterval = null; // Timer interval reference
                
                // DOM elements
                this.puzzleGrid = document.getElementById('puzzleGrid');
                this.moveCounter = document.getElementById('moveCount');
                this.timeDisplay = document.getElementById('timeDisplay');
                this.startBtn = document.getElementById('startBtn');
                this.resetBtn = document.getElementById('resetBtn');
                this.victoryMessage = document.getElementById('victoryMessage');
                this.victoryMoves = document.getElementById('victoryMoves');
                this.victoryTime = document.getElementById('victoryTime');
                this.victoryReturnBtn = document.getElementById('victoryReturnBtn');
                
                // Initialize the game
                this.init();
            }
            
            /**
             * Initialize the game board and event listeners
             */
            init() {
                this.createBoard();
                this.renderBoard();
                this.bindEvents();
            }
            
            /**
             * Create the initial solved board configuration
             */
            createBoard() {
                this.board = [];
                for (let y = 0; y < 4; y++) {
                    this.board[y] = [];
                    for (let x = 0; x < 4; x++) {
                        if (y === 3 && x === 3) {
                            this.board[y][x] = 0; // Empty tile
                        } else {
                            this.board[y][x] = y * 4 + x + 1; // Numbers 1-15
                        }
                    }
                }
                this.emptyPos = {x: 3, y: 3};
            }
            
            /**
             * Render the current board state to the DOM
             */
            renderBoard() {
                this.puzzleGrid.innerHTML = '';
                
                for (let y = 0; y < 4; y++) {
                    for (let x = 0; x < 4; x++) {
                        const tile = document.createElement('div');
                        tile.className = 'tile';
                        tile.dataset.x = x;
                        tile.dataset.y = y;
                        
                        if (this.board[y][x] === 0) {
                            tile.classList.add('empty');
                            tile.innerHTML = '';
                        } else {
                            tile.innerHTML = this.board[y][x];
                            tile.addEventListener('click', () => this.moveTile(x, y));
                        }
                        
                        this.puzzleGrid.appendChild(tile);
                    }
                }
            }
            
            /**
             * Bind event listeners for controls and keyboard input
             */
            bindEvents() {
                // Button event listeners
                this.startBtn.addEventListener('click', () => this.startGame());
                this.resetBtn.addEventListener('click', () => this.resetGame());
                this.victoryReturnBtn.addEventListener('click', () => this.hideVictory());
                
                // Keyboard event listener for arrow keys
                document.addEventListener('keydown', (e) => {
                    if (!this.gameStarted || this.gameWon) return;
                    
                    switch(e.key) {
                        case 'ArrowUp':
                            e.preventDefault();
                            this.moveEmptyTile(0, 1); // Move empty tile down (tile moves up)
                            break;
                        case 'ArrowDown':
                            e.preventDefault();
                            this.moveEmptyTile(0, -1); // Move empty tile up (tile moves down)
                            break;
                        case 'ArrowLeft':
                            e.preventDefault();
                            this.moveEmptyTile(1, 0); // Move empty tile right (tile moves left)
                            break;
                        case 'ArrowRight':
                            e.preventDefault();
                            this.moveEmptyTile(-1, 0); // Move empty tile left (tile moves right)
                            break;
                    }
                });
            }
            
            /**
             * Start a new game by shuffling the board
             */
            startGame() {
                this.shuffleBoard();
                this.gameStarted = true;
                this.gameWon = false;
                this.moves = 0;
                this.startTime = Date.now();
                
                this.updateMoveCounter();
                this.startTimer();
                
                this.startBtn.innerHTML = '<i class="fas fa-sync mr-2"></i>Shuffle';
            }
            
            /**
             * Reset the game to initial state
             */
            resetGame() {
                this.createBoard();
                this.renderBoard();
                this.gameStarted = false;
                this.gameWon = false;
                this.moves = 0;
                this.stopTimer();
                
                this.updateMoveCounter();
                this.updateTimeDisplay(0);
                
                this.startBtn.innerHTML = '<i class="fas fa-play mr-2"></i>Start Game';
            }
            
            /**
             * Shuffle the board using valid moves to ensure solvability
             */
            shuffleBoard() {
                // Perform 200 random valid moves to shuffle
                for (let i = 0; i < 200; i++) {
                    const possibleMoves = this.getPossibleMoves();
                    if (possibleMoves.length > 0) {
                        const randomMove = possibleMoves[Math.floor(Math.random() * possibleMoves.length)];
                        this.swapWithEmpty(randomMove.x, randomMove.y, false);
                    }
                }
                this.renderBoard();
            }
            
            /**
             * Get all possible moves (adjacent to empty tile)
             */
            getPossibleMoves() {
                const moves = [];
                const directions = [{x: 0, y: -1}, {x: 0, y: 1}, {x: -1, y: 0}, {x: 1, y: 0}];
                
                directions.forEach(dir => {
                    const newX = this.emptyPos.x + dir.x;
                    const newY = this.emptyPos.y + dir.y;
                    
                    if (this.isValidPosition(newX, newY)) {
                        moves.push({x: newX, y: newY});
                    }
                });
                
                return moves;
            }
            
            /**
             * Check if a position is valid (within board bounds)
             */
            isValidPosition(x, y) {
                return x >= 0 && x < 4 && y >= 0 && y < 4;
            }
            
            /**
             * Move a tile by clicking (swap with empty if adjacent)
             */
            moveTile(x, y) {
                if (!this.gameStarted || this.gameWon) return;
                
                // Check if the clicked tile is adjacent to empty tile
                const dx = Math.abs(x - this.emptyPos.x);
                const dy = Math.abs(y - this.emptyPos.y);
                
                if ((dx === 1 && dy === 0) || (dx === 0 && dy === 1)) {
                    this.swapWithEmpty(x, y, true);
                    this.renderBoard();
                    
                    if (this.checkWin()) {
                        this.gameWon = true;
                        this.stopTimer();
                        this.showVictory();
                    }
                }
            }
            
            /**
             * Move empty tile using arrow keys
             */
            moveEmptyTile(dx, dy) {
                const newX = this.emptyPos.x + dx;
                const newY = this.emptyPos.y + dy;
                
                if (this.isValidPosition(newX, newY)) {
                    this.swapWithEmpty(newX, newY, true);
                    this.renderBoard();
                    
                    if (this.checkWin()) {
                        this.gameWon = true;
                        this.stopTimer();
                        this.showVictory();
                    }
                }
            }
            
            /**
             * Swap a tile with the empty position
             */
            swapWithEmpty(x, y, countMove = false) {
                // Swap the values
                this.board[this.emptyPos.y][this.emptyPos.x] = this.board[y][x];
                this.board[y][x] = 0;
                
                // Update empty position
                this.emptyPos = {x, y};
                
                // Count move if it's a player move
                if (countMove) {
                    this.moves++;
                    this.updateMoveCounter();
                }
            }
            
            /**
             * Check if the puzzle is solved
             */
            checkWin() {
                for (let y = 0; y < 4; y++) {
                    for (let x = 0; x < 4; x++) {
                        const expectedValue = (y === 3 && x === 3) ? 0 : y * 4 + x + 1;
                        if (this.board[y][x] !== expectedValue) {
                            return false;
                        }
                    }
                }
                return true;
            }
            
            /**
             * Display victory animation and message
             */
            showVictory() {
                // Add victory animation to all tiles
                const tiles = document.querySelectorAll('.tile:not(.empty)');
                tiles.forEach((tile, index) => {
                    setTimeout(() => {
                        tile.classList.add('victory-tile');
                    }, index * 100);
                });
                
                // Update victory stats
                this.victoryMoves.textContent = this.moves;
                this.victoryTime.textContent = this.getFormattedTime();
                
                // Show victory message
                setTimeout(() => {
                    this.victoryMessage.style.display = 'flex';
                }, 1000);
            }
            
            /**
             * Hide victory message and reset game
             */
            hideVictory() {
                this.victoryMessage.style.display = 'none';
                this.resetGame();
            }
            
            /**
             * Update the move counter display
             */
            updateMoveCounter() {
                this.moveCounter.textContent = this.moves;
            }
            
            /**
             * Start the game timer
             */
            startTimer() {
                this.stopTimer(); // Clear any existing timer
                this.timerInterval = setInterval(() => {
                    const elapsed = Date.now() - this.startTime;
                    this.updateTimeDisplay(elapsed);
                }, 100);
            }
            
            /**
             * Stop the game timer
             */
            stopTimer() {
                if (this.timerInterval) {
                    clearInterval(this.timerInterval);
                    this.timerInterval = null;
                }
            }
            
            /**
             * Update the time display
             */
            updateTimeDisplay(elapsed) {
                const seconds = Math.floor(elapsed / 1000);
                const minutes = Math.floor(seconds / 60);
                const displaySeconds = seconds % 60;
                
                this.timeDisplay.textContent = 
                    `${minutes.toString().padStart(2, '0')}:${displaySeconds.toString().padStart(2, '0')}`;
            }
            
            /**
             * Get formatted time string
             */
            getFormattedTime() {
                if (!this.startTime) return '00:00';
                const elapsed = Date.now() - this.startTime;
                const seconds = Math.floor(elapsed / 1000);
                const minutes = Math.floor(seconds / 60);
                const displaySeconds = seconds % 60;
                
                return `${minutes.toString().padStart(2, '0')}:${displaySeconds.toString().padStart(2, '0')}`;
            }
        }
        
        // Initialize the game when DOM is loaded
        document.addEventListener('DOMContentLoaded', () => {
            new NumberFlowPro();
            
            // Initialize angel mascot eye tracking
            const angelFace = document.getElementById('angelFace');
            const leftPupil = document.getElementById('leftPupil');
            const rightPupil = document.getElementById('rightPupil');
            
            if (angelFace && leftPupil && rightPupil) {
                document.addEventListener('mousemove', function(e) {
                    const rect = angelFace.getBoundingClientRect();
                    const faceCenterX = rect.left + rect.width / 2;
                    const faceCenterY = rect.top + rect.height / 2;
                    
                    const angle = Math.atan2(e.clientY - faceCenterY, e.clientX - faceCenterX);
                    
                    const maxMovement = 1.5;
                    const pupilX = Math.cos(angle) * maxMovement;
                    const pupilY = Math.sin(angle) * maxMovement;
                    
                    leftPupil.style.transform = `translate(calc(-50% + ${pupilX}px), calc(-50% + ${pupilY}px)`;
                    rightPupil.style.transform = `translate(calc(-50% + ${pupilX}px), calc(-50% + ${pupilY}px)`;
                });
                
                document.addEventListener('mouseleave', function() {
                    leftPupil.style.transform = 'translate(-50%, -50%)';
                    rightPupil.style.transform = 'translate(-50%, -50%)';
                });
            }
        });
    </script>
</body>
</html>