:root {
            --primary-color: #ff6b00;
            --secondary-color: #2c3e50;
            --accent-color: #e74c3c;
            --text-color: #333;
            --light-bg: #f8f9fa;
        }
        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            line-height: 1.7;
            color: var(--text-color);
            background-color: #fff;
        }
        .navbar-brand {
            font-weight: 800;
            font-size: 1.8rem;
            color: var(--primary-color) !important;
            text-shadow: 1px 1px 2px rgba(0,0,0,0.1);
        }
        .nav-link {
            font-weight: 600;
            transition: color 0.3s ease;
        }
        .nav-link:hover {
            color: var(--primary-color) !important;
        }
        .hero-section {
            background: linear-gradient(135deg, var(--secondary-color) 0%, #34495e 100%);
            color: white;
            padding: 4rem 0;
            margin-bottom: 2rem;
        }
        .section-title {
            color: var(--secondary-color);
            border-left: 5px solid var(--primary-color);
            padding-left: 15px;
            margin: 2rem 0 1.5rem;
        }
        .content-card {
            background: white;
            border-radius: 10px;
            box-shadow: 0 5px 15px rgba(0,0,0,0.05);
            padding: 1.5rem;
            margin-bottom: 1.5rem;
            transition: transform 0.3s ease, box-shadow 0.3s ease;
        }
        .content-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 10px 25px rgba(0,0,0,0.1);
        }
        .highlight-text {
            background: linear-gradient(120deg, #ff6b0080 0%, #ff6b0080 100%);
            background-repeat: no-repeat;
            background-size: 100% 0.4em;
            background-position: 0 88%;
            font-weight: 700;
        }
        .feature-icon {
            color: var(--primary-color);
            font-size: 1.5rem;
            margin-right: 10px;
        }
        .img-fluid {
            border-radius: 8px;
            box-shadow: 0 5px 15px rgba(0,0,0,0.1);
            transition: transform 0.3s ease;
        }
        .img-fluid:hover {
            transform: scale(1.02);
        }
        .table-of-contents {
            background-color: var(--light-bg);
            border-radius: 10px;
            padding: 1.5rem;
            margin-bottom: 2rem;
        }
        .toc-item {
            margin-bottom: 0.5rem;
            padding-left: 1rem;
            border-left: 3px solid transparent;
            transition: all 0.3s ease;
        }
        .toc-item:hover {
            border-left: 3px solid var(--primary-color);
            padding-left: 1.2rem;
        }
        .toc-link {
            text-decoration: none;
            color: var(--text-color);
            font-weight: 500;
        }
        .toc-link:hover {
            color: var(--primary-color);
        }
        footer {
            background-color: var(--secondary-color);
            color: white;
            padding: 2rem 0;
            margin-top: 3rem;
        }
        @media (max-width: 768px) {
            .hero-section {
                padding: 2rem 0;
            }
            .navbar-brand {
                font-size: 1.5rem;
            }
            .content-card {
                padding: 1rem;
            }
        }