:root {
            --primary-color: #2E8B57;
            --secondary-color: #FF6B35;
            --accent-color: #1E40AF;
            --text-dark: #1F2937;
            --text-light: #6B7280;
            --bg-light: #F9FAFB;
        }
        body {
            font-family: 'Segoe UI', system-ui, sans-serif;
            line-height: 1.7;
            color: var(--text-dark);
            background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
        }
        .navbar-brand {
            font-weight: 800;
            font-size: 1.8rem;
            background: linear-gradient(45deg, var(--primary-color), var(--secondary-color));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            text-shadow: 2px 2px 4px rgba(0,0,0,0.1);
        }
        .hero-section {
            background: linear-gradient(rgba(0,0,0,0.7), rgba(0,0,0,0.7)), url('https://via.placeholder.com/1200x600') center/cover no-repeat;
            color: white;
            padding: 100px 0;
            text-align: center;
            border-radius: 0 0 30px 30px;
            margin-bottom: 40px;
        }
        .content-section {
            background: white;
            border-radius: 15px;
            box-shadow: 0 10px 30px rgba(0,0,0,0.1);
            padding: 40px;
            margin-bottom: 30px;
            transition: transform 0.3s ease;
        }
        .content-section:hover {
            transform: translateY(-5px);
        }
        h1, h2, h3 {
            color: var(--primary-color);
            margin-bottom: 1.5rem;
            font-weight: 700;
        }
        h1 {
            font-size: 2.5rem;
            text-shadow: 1px 1px 2px rgba(0,0,0,0.1);
        }
        h2 {
            font-size: 2rem;
            border-left: 5px solid var(--secondary-color);
            padding-left: 15px;
        }
        h3 {
            font-size: 1.5rem;
            color: var(--accent-color);
        }
        .keyword-highlight {
            background-color: rgba(255, 107, 53, 0.2);
            padding: 2px 6px;
            border-radius: 4px;
            font-weight: 600;
        }
        .feature-icon {
            font-size: 2rem;
            color: var(--primary-color);
            margin-bottom: 15px;
        }
        .img-container {
            border-radius: 10px;
            overflow: hidden;
            box-shadow: 0 5px 15px rgba(0,0,0,0.1);
            margin: 25px 0;
        }
        .img-container img {
            transition: transform 0.5s ease;
        }
        .img-container:hover img {
            transform: scale(1.03);
        }
        .table-of-contents {
            background: var(--bg-light);
            border-radius: 10px;
            padding: 25px;
            margin-bottom: 30px;
            border-left: 4px solid var(--primary-color);
        }
        .table-of-contents ul {
            list-style-type: none;
            padding-left: 0;
        }
        .table-of-contents li {
            margin-bottom: 10px;
            padding-left: 20px;
            position: relative;
        }
        .table-of-contents li:before {
            content: "▶";
            position: absolute;
            left: 0;
            color: var(--secondary-color);
        }
        .table-of-contents a {
            text-decoration: none;
            color: var(--text-dark);
            transition: color 0.3s ease;
        }
        .table-of-contents a:hover {
            color: var(--primary-color);
        }
        .stats-box {
            background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
            color: white;
            border-radius: 10px;
            padding: 20px;
            text-align: center;
            margin: 20px 0;
        }
        .tip-box {
            background-color: #E1F5FE;
            border-left: 4px solid #0288D1;
            padding: 20px;
            border-radius: 0 8px 8px 0;
            margin: 20px 0;
        }
        footer {
            background-color: var(--text-dark);
            color: white;
            padding: 40px 0 20px;
            margin-top: 50px;
        }
        @media (max-width: 768px) {
            .hero-section {
                padding: 60px 0;
            }
            h1 {
                font-size: 2rem;
            }
            h2 {
                font-size: 1.7rem;
            }
            .content-section {
                padding: 25px;
            }
        }