* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
        }

        :root {
            --primary-color: #4a6fa5;
            --secondary-color: #6e9cd2;
            --accent-color: #ff9e40;
            --light-color: #f8f9fa;
            --dark-color: #343a40;
            --gray-color: #6c757d;
            --success-color: #28a745;
            --danger-color: #dc3545;
            --border-radius: 8px;
            --box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
        }

        body {
            background-color: #f5f7fa;
            color: #333;
            line-height: 1.6;
            min-height: 100vh;
            display: flex;
            flex-direction: column;
        }

        /* Header Styles */
        header {
            background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
            color: white;
            padding: 1rem 2rem;
            box-shadow: var(--box-shadow);
            position: relative;
        }

        .header-container {
            max-width: 1200px;
            margin: 0 auto;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .logo {
            font-size: 1.8rem;
            font-weight: 700;
            display: flex;
            align-items: center;
        }

        .logo i {
            margin-right: 10px;
            color: var(--accent-color);
        }

        .nav-desktop {
            display: flex;
        }

        .nav-desktop a {
            color: white;
            text-decoration: none;
            margin-left: 1.5rem;
            font-weight: 500;
            transition: color 0.3s;
        }

        .nav-desktop a:hover {
            color: var(--accent-color);
        }

        .mobile-toggle {
            display: none;
            font-size: 1.5rem;
            background: none;
            border: none;
            color: white;
            cursor: pointer;
        }

        .nav-mobile {
            display: none;
            flex-direction: column;
            background-color: var(--primary-color);
            position: absolute;
            top: 100%;
            left: 0;
            right: 0;
            padding: 1rem;
            box-shadow: var(--box-shadow);
            z-index: 1000;
        }

        .nav-mobile.active {
            display: flex;
        }

        .nav-mobile a {
            color: white;
            text-decoration: none;
            padding: 0.8rem 0;
            border-bottom: 1px solid rgba(255, 255, 255, 0.1);
            display: flex;
            align-items: center;
        }

        .nav-mobile a i {
            margin-right: 10px;
            width: 20px;
        }

        /* Main Content */
        main {
            flex: 1;
            padding: 2rem;
            max-width: 1200px;
            margin: 0 auto;
            width: 100%;
        }

        .page-title {
            text-align: center;
            margin-bottom: 2rem;
            color: var(--primary-color);
        }

        .game-container {
            display: flex;
            flex-direction: column;
            align-items: center;
            background: white;
            border-radius: var(--border-radius);
            padding: 2rem;
            box-shadow: var(--box-shadow);
            margin-bottom: 2rem;
        }

        .prediction-section {
            display: flex;
            flex-direction: column;
            align-items: center;
            margin-bottom: 2rem;
            width: 100%;
        }

        .prediction-buttons {
            display: flex;
            gap: 1.5rem;
            margin-bottom: 2rem;
            flex-wrap: wrap;
            justify-content: center;
        }

        .prediction-btn {
            padding: 1.2rem 2.5rem;
            border: 2px solid var(--primary-color);
            border-radius: var(--border-radius);
            background: white;
            font-size: 1.2rem;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s;
            display: flex;
            align-items: center;
            gap: 0.8rem;
            min-width: 150px;
            justify-content: center;
        }

        .prediction-btn.active {
            background: var(--primary-color);
            color: white;
        }

        .prediction-btn:hover:not(.active) {
            transform: translateY(-3px);
            box-shadow: var(--box-shadow);
        }

        .coin-container {
            position: relative;
            width: 180px;
            height: 180px;
            margin: 2rem 0;
            perspective: 1000px;
        }

        .coin {
            width: 100%;
            height: 100%;
            position: relative;
            transform-style: preserve-3d;
            transition: transform 1.2s ease-out;
        }

        .coin-face {
            position: absolute;
            width: 100%;
            height: 100%;
            border-radius: 50%;
            backface-visibility: hidden;
            display: flex;
            justify-content: center;
            align-items: center;
            font-size: 4.5rem;
            background: linear-gradient(45deg, #d4af37, #f9d423);
            box-shadow: 0 0 15px rgba(0, 0, 0, 0.2);
            border: 6px solid #c19b2a;
            color: #2c3e50;
        }

        .heads {
            background: linear-gradient(45deg, #d4af37, #f9d423);
        }

        .tails {
            background: linear-gradient(45deg, #c19b2a, #e6c252);
            transform: rotateY(180deg);
        }

        .coin.flipping {
            animation: flip 1.2s ease-out forwards;
        }

        @keyframes flip {
            0% { transform: rotateY(0); }
            100% { transform: rotateY(1980deg); }
        }

        .result-display {
            text-align: center;
            margin: 1.5rem 0;
            font-size: 1.5rem;
            font-weight: 600;
            min-height: 2.5rem;
            padding: 0.8rem 1.5rem;
            border-radius: var(--border-radius);
            background-color: var(--light-color);
            width: 100%;
            max-width: 400px;
        }

        .win {
            color: var(--success-color);
            background-color: rgba(40, 167, 69, 0.1);
            border: 1px solid var(--success-color);
        }

        .lose {
            color: var(--danger-color);
            background-color: rgba(220, 53, 69, 0.1);
            border: 1px solid var(--danger-color);
        }

        .controls {
            display: flex;
            flex-wrap: wrap;
            gap: 1rem;
            justify-content: center;
            margin-bottom: 1.5rem;
            width: 100%;
        }

        .btn {
            padding: 0.9rem 1.8rem;
            border: none;
            border-radius: var(--border-radius);
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s;
            display: flex;
            align-items: center;
            gap: 0.5rem;
        }

        .btn-primary {
            background-color: var(--primary-color);
            color: white;
        }

        .btn-primary:hover:not(:disabled) {
            background-color: var(--secondary-color);
            transform: translateY(-2px);
        }

        .btn-primary:disabled {
            background-color: var(--gray-color);
            cursor: not-allowed;
        }

        .btn-secondary {
            background-color: var(--light-color);
            color: var(--dark-color);
            border: 1px solid #ddd;
        }

        .btn-secondary:hover {
            background-color: #e9ecef;
            transform: translateY(-2px);
        }

        .stats-container {
            display: flex;
            justify-content: space-around;
            width: 100%;
            margin-top: 2rem;
            padding-top: 2rem;
            border-top: 1px solid #eee;
            flex-wrap: wrap;
            gap: 1.5rem;
        }

        .stat-box {
            text-align: center;
            flex: 1;
            min-width: 120px;
            padding: 1rem;
            background: var(--light-color);
            border-radius: var(--border-radius);
            box-shadow: var(--box-shadow);
        }

        .stat-value {
            font-size: 2rem;
            font-weight: 700;
            color: var(--primary-color);
            margin-bottom: 0.3rem;
        }

        .stat-label {
            font-size: 0.9rem;
            color: var(--gray-color);
            font-weight: 500;
        }

        .history-container {
            background: white;
            border-radius: var(--border-radius);
            padding: 2rem;
            box-shadow: var(--box-shadow);
            margin-bottom: 2rem;
        }

        .history-title {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 1.5rem;
            padding-bottom: 0.8rem;
            border-bottom: 2px solid var(--light-color);
            flex-wrap: wrap;
            gap: 1rem;
        }

        .history-list {
            max-height: 300px;
            overflow-y: auto;
        }

        .history-item {
            display: flex;
            justify-content: space-between;
            padding: 1rem 0;
            border-bottom: 1px solid #eee;
            align-items: center;
        }

        .history-item:last-child {
            border-bottom: none;
        }

        .history-timestamp {
            color: var(--gray-color);
            font-size: 0.9rem;
        }

        .history-result {
            font-weight: 600;
            display: flex;
            align-items: center;
            gap: 0.5rem;
        }

        .history-win {
            color: var(--success-color);
        }

        .history-lose {
            color: var(--danger-color);
        }

        .seo-section {
            background: white;
            border-radius: var(--border-radius);
            padding: 2rem;
            box-shadow: var(--box-shadow);
            margin-bottom: 2rem;
        }

        .seo-section h2 {
            color: var(--primary-color);
            margin-bottom: 1rem;
        }

        .seo-section p {
            margin-bottom: 1rem;
            line-height: 1.8;
        }

        .seo-section ul {
            margin-left: 2rem;
            margin-bottom: 1rem;
        }

        .seo-section li {
            margin-bottom: 0.8rem;
            line-height: 1.6;
        }

        /* Footer Styles */
        footer {
            background-color: var(--dark-color);
            color: white;
            padding: 3rem 2rem 1.5rem;
            margin-top: 2rem;
        }

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

        .footer-section h3 {
            font-size: 1.2rem;
            margin-bottom: 1.2rem;
            color: var(--accent-color);
        }

        .footer-links {
            list-style: none;
        }

        .footer-links li {
            margin-bottom: 0.8rem;
        }

        .footer-links a {
            color: #ddd;
            text-decoration: none;
            transition: color 0.3s;
            display: flex;
            align-items: center;
        }

        .footer-links a i {
            margin-right: 8px;
            width: 20px;
        }

        .footer-links a:hover {
            color: var(--accent-color);
        }

        .copyright {
            text-align: center;
            margin-top: 3rem;
            padding-top: 1.5rem;
            border-top: 1px solid rgba(255, 255, 255, 0.1);
            color: #aaa;
            font-size: 0.9rem;
        }

        /* Responsive Design */
        @media (max-width: 768px) {
            .header-container {
                padding: 0;
            }

            .nav-desktop {
                display: none;
            }

            .mobile-toggle {
                display: block;
            }

            .prediction-buttons {
                flex-direction: column;
                width: 100%;
                align-items: center;
            }

            .prediction-btn {
                width: 100%;
                max-width: 250px;
                justify-content: center;
            }

            .coin-container {
                width: 150px;
                height: 150px;
            }

            .coin-face {
                font-size: 3.5rem;
            }

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

            .btn {
                width: 100%;
                max-width: 300px;
                justify-content: center;
            }
            
            .history-title {
                flex-direction: column;
                align-items: flex-start;
            }

            .stats-container {
                gap: 1rem;
            }

            .stat-box {
                min-width: calc(50% - 1rem);
            }
        }

        @media (max-width: 480px) {
            header {
                padding: 1rem;
            }
            
            .logo {
                font-size: 1.5rem;
            }

            .coin-container {
                width: 130px;
                height: 130px;
            }

            .coin-face {
                font-size: 3rem;
                border-width: 4px;
            }
            
            main {
                padding: 1rem;
            }
            
            .game-container, .history-container, .seo-section {
                padding: 1.5rem;
            }

            .stat-box {
                min-width: 100%;
            }

            .history-item {
                flex-direction: column;
                align-items: flex-start;
                gap: 0.5rem;
            }

            .history-timestamp {
                margin-left: 1.7rem;
            }
        }