:root {
            --primary-color: #1a365d;
            --secondary-color: #e63946;
            --accent-color: #f4a261;
            --light-color: #f8f9fa;
            --dark-color: #343a40;
        }
        body {
            font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
            line-height: 1.6;
            color: #333;
        }
        .navbar-brand {
            font-weight: 700;
            font-size: 1.8rem;
            color: var(--primary-color);
        }
        .hero-section {
            background: linear-gradient(rgba(26, 54, 93, 0.8), rgba(26, 54, 93, 0.9)), url('https://images.unsplash.com/photo-1497366754035-f200968a6e72?ixlib=rb-4.0.3&auto=format&fit=crop&w=1600&q=80') center/cover no-repeat;
            color: white;
            padding: 150px 0;
        }
        .section-title {
            color: var(--primary-color);
            border-left: 5px solid var(--secondary-color);
            padding-left: 15px;
            margin-bottom: 2rem;
        }
        .card {
            transition: transform 0.3s ease, box-shadow 0.3s ease;
            border: none;
            box-shadow: 0 4px 6px rgba(0,0,0,0.1);
        }
        .card:hover {
            transform: translateY(-10px);
            box-shadow: 0 10px 20px rgba(0,0,0,0.15);
        }
        .btn-primary {
            background-color: var(--primary-color);
            border-color: var(--primary-color);
            padding: 10px 30px;
            font-weight: 600;
        }
        .btn-primary:hover {
            background-color: #0d284c;
            border-color: #0d284c;
        }
        .flink {
            display: inline-block;
            padding: 10px 20px;
            margin: 5px;
            background-color: #f8f9fa;
            border-radius: 5px;
            color: var(--primary-color);
            text-decoration: none;
            transition: all 0.3s ease;
            border: 1px solid #dee2e6;
        }
        .flink:hover {
            background-color: var(--primary-color);
            color: white;
            transform: scale(1.05);
        }
        .friendlink {
            background-color: #f8f9fa;
            padding: 60px 0;
        }
        footer {
            background-color: var(--primary-color);
            color: white;
        }
        .social-icons a {
            color: white;
            font-size: 1.5rem;
            margin: 0 10px;
            transition: color 0.3s ease;
        }
        .social-icons a:hover {
            color: var(--accent-color);
        }
        .img-fluid {
            border-radius: 8px;
        }
        @media (max-width: 768px) {
            .hero-section {
                padding: 100px 0;
            }
            .display-4 {
                font-size: 2.5rem;
            }
        }