:root {
            --primary-color: #ff6b35;
            --secondary-color: #f7931e;
            --accent-color: #2e3192;
            --text-dark: #2d3748;
            --text-light: #718096;
            --bg-light: #f7fafc;
        }
        body {
            font-family: 'Segoe UI', system-ui, sans-serif;
            line-height: 1.7;
            color: var(--text-dark);
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
        }
        .main-container {
            background: white;
            border-radius: 20px;
            box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
            overflow: hidden;
            margin-top: 2rem;
            margin-bottom: 2rem;
        }
        .logo-header {
            background: linear-gradient(45deg, var(--primary-color), var(--secondary-color));
            padding: 2rem 0;
            text-align: center;
            color: white;
            position: relative;
            overflow: hidden;
        }
        .logo-text {
            font-size: 3.5rem;
            font-weight: 900;
            text-shadow: 3px 3px 0 rgba(0,0,0,0.2);
            letter-spacing: 2px;
            margin: 0;
        }
        .logo-subtitle {
            font-size: 1.2rem;
            opacity: 0.9;
            margin-top: 0.5rem;
        }
        .nav-custom {
            background: var(--accent-color);
            padding: 0;
        }
        .nav-custom .nav-link {
            color: white !important;
            font-weight: 600;
            padding: 1rem 1.5rem;
            transition: all 0.3s ease;
            border-bottom: 3px solid transparent;
        }
        .nav-custom .nav-link:hover {
            background: rgba(255,255,255,0.1);
            border-bottom: 3px solid var(--secondary-color);
        }
        .content-section {
            padding: 3rem 2rem;
        }
        h1, h2, h3 {
            color: var(--accent-color);
            margin-bottom: 1.5rem;
            font-weight: 700;
        }
        h1 {
            font-size: 2.8rem;
            border-bottom: 4px solid var(--primary-color);
            padding-bottom: 0.5rem;
            display: inline-block;
        }
        h2 {
            font-size: 2.2rem;
            margin-top: 3rem;
            position: relative;
            padding-left: 1rem;
        }
        h2:before {
            content: '';
            position: absolute;
            left: 0;
            top: 0;
            height: 100%;
            width: 5px;
            background: var(--primary-color);
            border-radius: 5px;
        }
        h3 {
            font-size: 1.8rem;
            color: var(--secondary-color);
            margin-top: 2.5rem;
        }
        p {
            margin-bottom: 1.5rem;
            font-size: 1.1rem;
            text-align: justify;
        }
        .highlight-box {
            background: linear-gradient(135deg, #fff9e6, #ffeacc);
            border-left: 5px solid var(--secondary-color);
            padding: 1.5rem;
            margin: 2rem 0;
            border-radius: 0 10px 10px 0;
            box-shadow: 0 5px 15px rgba(0,0,0,0.05);
        }
        .game-feature {
            background: var(--bg-light);
            padding: 1.5rem;
            border-radius: 10px;
            margin: 1.5rem 0;
            transition: transform 0.3s ease, box-shadow 0.3s ease;
            border: 1px solid #e2e8f0;
        }
        .game-feature:hover {
            transform: translateY(-5px);
            box-shadow: 0 10px 25px rgba(0,0,0,0.1);
        }
        .feature-icon {
            font-size: 2.5rem;
            color: var(--primary-color);
            margin-bottom: 1rem;
        }
        .img-container {
            margin: 2.5rem 0;
            text-align: center;
            position: relative;
        }
        .img-container img {
            max-width: 100%;
            height: auto;
            border-radius: 15px;
            box-shadow: 0 15px 30px rgba(0,0,0,0.15);
            transition: transform 0.5s ease;
        }
        .img-container img:hover {
            transform: scale(1.02);
        }
        .img-caption {
            margin-top: 1rem;
            font-style: italic;
            color: var(--text-light);
            font-size: 0.95rem;
        }
        .key-term {
            font-weight: 700;
            color: var(--primary-color);
            background: rgba(255, 107, 53, 0.1);
            padding: 0.2rem 0.5rem;
            border-radius: 4px;
        }
        footer {
            background: var(--accent-color);
            color: white;
            padding: 2.5rem 0;
            margin-top: 3rem;
        }
        .back-to-top {
            position: fixed;
            bottom: 30px;
            right: 30px;
            background: var(--primary-color);
            color: white;
            width: 50px;
            height: 50px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.5rem;
            box-shadow: 0 5px 15px rgba(0,0,0,0.2);
            cursor: pointer;
            opacity: 0;
            transition: all 0.3s ease;
            z-index: 1000;
        }
        .back-to-top.show {
            opacity: 1;
        }
        @media (max-width: 768px) {
            .logo-text {
                font-size: 2.5rem;
            }
            h1 {
                font-size: 2.2rem;
            }
            h2 {
                font-size: 1.8rem;
            }
            h3 {
                font-size: 1.5rem;
            }
            .content-section {
                padding: 2rem 1rem;
            }
        }
        .content-highlight {
            background: linear-gradient(135deg, #e3f2fd, #bbdefb);
            padding: 2rem;
            border-radius: 15px;
            margin: 2.5rem 0;
            border: 2px dashed var(--accent-color);
        }
        .stat-number {
            font-size: 3rem;
            font-weight: 900;
            color: var(--primary-color);
            display: block;
            line-height: 1;
        }
        .stat-label {
            font-size: 1.2rem;
            color: var(--accent-color);
            font-weight: 600;
        }
        .quote-box {
            border-left: 5px solid var(--secondary-color);
            padding-left: 1.5rem;
            margin: 2rem 0;
            font-style: italic;
            color: var(--text-light);
            background: rgba(247, 147, 30, 0.05);
            padding: 1.5rem;
            border-radius: 0 10px 10px 0;
        }