:root {
            --primary-color: #ff6b35;
            --secondary-color: #1e3a8a;
            --accent-color: #f59e0b;
            --dark-color: #1f2937;
            --light-color: #f8fafc;
        }
        body {
            font-family: 'Segoe UI', system-ui, sans-serif;
            line-height: 1.7;
            color: #333;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            min-height: 100vh;
        }
        .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 {
            font-family: 'Impact', 'Arial Black', sans-serif;
            font-size: 2.5rem;
            font-weight: 900;
            background: linear-gradient(45deg, #ff6b35, #f59e0b);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            text-transform: uppercase;
            letter-spacing: 2px;
        }
        .nav-link {
            font-weight: 600;
            color: var(--dark-color) !important;
            transition: all 0.3s ease;
            border-bottom: 3px solid transparent;
        }
        .nav-link:hover, .nav-link.active {
            color: var(--primary-color) !important;
            border-bottom: 3px solid var(--primary-color);
        }
        h1, h2, h3 {
            color: var(--secondary-color);
            font-weight: 700;
            margin-bottom: 1.5rem;
        }
        h1 {
            font-size: 2.8rem;
            border-left: 6px solid var(--primary-color);
            padding-left: 1rem;
            margin-top: 2rem;
        }
        h2 {
            font-size: 2.2rem;
            border-bottom: 3px solid var(--accent-color);
            padding-bottom: 0.5rem;
            margin-top: 3rem;
        }
        h3 {
            font-size: 1.8rem;
            color: var(--primary-color);
            margin-top: 2.5rem;
        }
        .highlight {
            background: linear-gradient(120deg, #f59e0b20 0%, #f59e0b20 100%);
            padding: 2rem;
            border-radius: 12px;
            border-left: 5px solid var(--accent-color);
            margin: 2rem 0;
        }
        .key-point {
            background: var(--light-color);
            padding: 1.5rem;
            border-radius: 10px;
            margin: 1.5rem 0;
            box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
            transition: transform 0.3s ease;
        }
        .key-point:hover {
            transform: translateY(-5px);
        }
        .feature-icon {
            font-size: 2.5rem;
            color: var(--primary-color);
            margin-bottom: 1rem;
        }
        .img-container {
            border-radius: 15px;
            overflow: hidden;
            box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
            margin: 2rem 0;
            transition: transform 0.3s ease;
        }
        .img-container:hover {
            transform: scale(1.02);
        }
        footer {
            background: var(--dark-color);
            color: white;
            padding: 3rem 0;
            margin-top: 4rem;
        }
        .section-divider {
            height: 4px;
            background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
            margin: 3rem 0;
            border-radius: 2px;
        }
        @media (max-width: 768px) {
            h1 { font-size: 2.2rem; }
            h2 { font-size: 1.8rem; }
            h3 { font-size: 1.5rem; }
            .logo { font-size: 1.8rem; }
        }
        .content-paragraph {
            margin-bottom: 1.8rem;
            text-align: justify;
        }
        .keyword {
            font-weight: 700;
            color: var(--primary-color);
        }
        .table-of-contents {
            background: var(--light-color);
            padding: 2rem;
            border-radius: 12px;
            margin: 2rem 0;
        }
        .toc-item {
            padding: 0.5rem 0;
            border-bottom: 1px solid #e5e7eb;
        }
        .toc-item:last-child {
            border-bottom: none;
        }