* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            min-height: 100vh;
            color: #333;
        }

        /* Header Styles */
        header {
            background: rgba(255, 255, 255, 0.95);
            backdrop-filter: blur(10px);
            box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
            position: sticky;
            top: 0;
            z-index: 1000;
        }

        nav {
            max-width: 1200px;
            margin: 0 auto;
            padding: 1rem 2rem;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .logo {
            font-size: 2rem;
            font-weight: bold;
            background: linear-gradient(45deg, #667eea, #764ba2);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }

        .nav-links {
            display: flex;
            list-style: none;
            gap: 2rem;
        }

        .nav-links a {
            text-decoration: none;
            color: #333;
            font-weight: 500;
            transition: color 0.3s ease;
        }

        .nav-links a:hover {
            color: #667eea;
        }

        /* Main Content */
        main {
            max-width: 1200px;
            margin: 0 auto;
            padding: 2rem;
        }

        .hero {
            text-align: center;
            margin-bottom: 3rem;
        }

        .hero h1 {
            font-size: 3.5rem;
            color: white;
            margin-bottom: 1rem;
            text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
        }

        .hero p {
            font-size: 1.2rem;
            color: rgba(255, 255, 255, 0.9);
            margin-bottom: 2rem;
        }

        /* Game Container */
        .game-container {
            background: rgba(255, 255, 255, 0.95);
            border-radius: 20px;
            padding: 2rem;
            box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
            margin: 0 auto;
            max-width: 800px;
            backdrop-filter: blur(10px);
        }

        .game-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 2rem;
            flex-wrap: wrap;
            gap: 1rem;
        }

        .game-title {
            font-size: 2.5rem;
            font-weight: bold;
            background: linear-gradient(45deg, #667eea, #764ba2);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }

        .game-stats {
            display: flex;
            gap: 2rem;
            align-items: center;
        }

        .stat {
            text-align: center;
        }

        .stat-value {
            font-size: 1.5rem;
            font-weight: bold;
            color: #667eea;
        }

        .stat-label {
            font-size: 0.9rem;
            color: #666;
        }

        /* Game Board */
        .game-board {
            display: flex;
            justify-content: center;
            align-items: flex-start;
            gap: 2rem;
            margin-bottom: 2rem;
        }

        .tetris-board {
            display: grid;
            grid-template-columns: repeat(10, 1fr);
            gap: 1px;
            background: #333;
            padding: 10px;
            border-radius: 10px;
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
        }

        .cell {
            width: 25px;
            height: 25px;
            background: #f0f0f0;
            border: 1px solid #ddd;
            transition: all 0.1s ease;
        }

        .cell.filled {
            border: 1px solid #fff;
            box-shadow: inset 0 0 5px rgba(0, 0, 0, 0.2);
        }

        /* Tetromino Colors */
        .cyan { background: #00bcd4; }
        .blue { background: #2196f3; }
        .orange { background: #ff9800; }
        .yellow { background: #ffeb3b; }
        .green { background: #4caf50; }
        .purple { background: #9c27b0; }
        .red { background: #f44336; }

        /* Next Piece Preview */
        .next-piece {
            background: rgba(255, 255, 255, 0.8);
            padding: 1rem;
            border-radius: 10px;
            text-align: center;
        }

        .next-piece h3 {
            margin-bottom: 1rem;
            color: #333;
        }

        .next-preview {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 2px;
            width: 80px;
            margin: 0 auto;
        }

        .next-cell {
            width: 18px;
            height: 18px;
            background: #f0f0f0;
            border: 1px solid #ddd;
        }

        /* Controls */
        .controls {
            display: flex;
            justify-content: center;
            gap: 1rem;
            margin-bottom: 2rem;
            flex-wrap: wrap;
        }

        .btn {
            padding: 0.8rem 1.5rem;
            border: none;
            border-radius: 25px;
            font-size: 1rem;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s ease;
            background: linear-gradient(45deg, #667eea, #764ba2);
            color: white;
            box-shadow: 0 4px 15px rgba(102, 126, 234, 0.3);
        }

        .btn:hover {
            transform: translateY(-2px);
            box-shadow: 0 6px 20px rgba(102, 126, 234, 0.4);
        }

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

        .btn.secondary {
            background: linear-gradient(45deg, #f093fb, #f5576c);
            box-shadow: 0 4px 15px rgba(240, 147, 251, 0.3);
        }

        .btn.secondary:hover {
            box-shadow: 0 6px 20px rgba(240, 147, 251, 0.4);
        }

        /* Instructions */
        .instructions {
            background: rgba(255, 255, 255, 0.8);
            padding: 1.5rem;
            border-radius: 10px;
            margin-top: 2rem;
        }

        .instructions h3 {
            margin-bottom: 1rem;
            color: #333;
        }

        .instructions ul {
            list-style: none;
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 0.5rem;
        }

        .instructions li {
            padding: 0.5rem;
            background: rgba(102, 126, 234, 0.1);
            border-radius: 5px;
        }

        /* Game Over Modal */
        .game-over {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: rgba(0, 0, 0, 0.8);
            display: none;
            justify-content: center;
            align-items: center;
            z-index: 2000;
        }

        .game-over-content {
            background: white;
            padding: 3rem;
            border-radius: 20px;
            text-align: center;
            box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
        }

        .game-over h2 {
            font-size: 2.5rem;
            color: #f44336;
            margin-bottom: 1rem;
        }

        /* Footer */
        footer {
            background: rgba(0, 0, 0, 0.8);
            color: white;
            padding: 3rem 2rem 1rem;
            margin-top: 4rem;
        }

        .footer-content {
            max-width: 1200px;
            margin: 0 auto;
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 2rem;
        }

        .footer-section h3 {
            margin-bottom: 1rem;
            color: #667eea;
        }

        .footer-section ul {
            list-style: none;
        }

        .footer-section a {
            color: rgba(255, 255, 255, 0.8);
            text-decoration: none;
            transition: color 0.3s ease;
        }

        .footer-section a:hover {
            color: #667eea;
        }

        .footer-bottom {
            text-align: center;
            padding-top: 2rem;
            margin-top: 2rem;
            border-top: 1px solid rgba(255, 255, 255, 0.2);
            color: rgba(255, 255, 255, 0.6);
        }

        /* Responsive Design */
        @media (max-width: 768px) {
            .nav-links {
                display: none;
            }

            .hero h1 {
                font-size: 2.5rem;
            }

            .game-board {
                flex-direction: column;
                align-items: center;
            }

            .game-header {
                flex-direction: column;
                text-align: center;
            }

            .cell {
                width: 20px;
                height: 20px;
            }
        }

        /* Animations */
        @keyframes fadeIn {
            from { opacity: 0; transform: translateY(20px); }
            to { opacity: 1; transform: translateY(0); }
        }

        .game-container {
            animation: fadeIn 0.6s ease-out;
        }

        @keyframes pulse {
            0%, 100% { transform: scale(1); }
            50% { transform: scale(1.05); }
        }

        .btn:hover {
            animation: pulse 0.6s ease-in-out;
        }