:root {
            --primary-color: #FF9933;
            --secondary-color: #138808;
            --accent-color: #000080;
            --text-dark: #333333;
            --text-light: #666666;
            --bg-light: #f8f9fa;
        }
        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, 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(--accent-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');
            background-size: cover;
            background-position: center;
            color: white;
            padding: 100px 0;
            text-align: center;
            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(--accent-color);
            margin-bottom: 1.5rem;
            font-weight: 700;
        }
        h1 {
            font-size: 2.8rem;
            text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
        }
        h2 {
            font-size: 2.2rem;
            border-left: 5px solid var(--primary-color);
            padding-left: 15px;
            margin-top: 2.5rem;
        }
        h3 {
            font-size: 1.8rem;
            color: var(--secondary-color);
            margin-top: 2rem;
        }
        p {
            margin-bottom: 1.5rem;
            font-size: 1.1rem;
            text-align: justify;
        }
        .key-point {
            background: linear-gradient(135deg, var(--bg-light), #e9ecef);
            border-left: 4px solid var(--primary-color);
            padding: 20px;
            margin: 25px 0;
            border-radius: 0 10px 10px 0;
        }
        .feature-icon {
            font-size: 2rem;
            color: var(--primary-color);
            margin-right: 15px;
            vertical-align: middle;
        }
        .img-fluid {
            border-radius: 10px;
            box-shadow: 0 5px 15px rgba(0,0,0,0.2);
            margin: 25px 0;
            transition: transform 0.3s ease;
        }
        .img-fluid:hover {
            transform: scale(1.02);
        }
        .nav-pills .nav-link {
            color: var(--text-dark);
            font-weight: 600;
            padding: 12px 20px;
            margin: 5px;
            border-radius: 25px;
            transition: all 0.3s ease;
        }
        .nav-pills .nav-link:hover, .nav-pills .nav-link.active {
            background: linear-gradient(45deg, var(--primary-color), var(--secondary-color));
            color: white;
            transform: translateY(-2px);
        }
        footer {
            background: linear-gradient(135deg, var(--accent-color), #1a237e);
            color: white;
            padding: 40px 0 20px;
            margin-top: 50px;
        }
        .content-highlight {
            background: linear-gradient(135deg, #fff3cd, #ffeaa7);
            padding: 25px;
            border-radius: 10px;
            border: 2px dashed var(--primary-color);
            margin: 30px 0;
        }
        @media (max-width: 768px) {
            .hero-section {
                padding: 60px 0;
            }
            h1 {
                font-size: 2.2rem;
            }
            h2 {
                font-size: 1.8rem;
            }
            .content-section {
                padding: 25px;
            }
        }
        .reading-progress {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 4px;
            background: var(--bg-light);
            z-index: 1000;
        }
        .reading-progress-bar {
            height: 100%;
            background: linear-gradient(45deg, var(--primary-color), var(--secondary-color));
            width: 0%;
            transition: width 0.3s ease;
        }