:root {
            --primary-color: #0056b3;
            --secondary-color: #17a2b8;
            --dark-color: #343a40;
            --light-color: #f8f9fa;
            --hover-color: #003d82;
        }
        body {
            font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
            line-height: 1.6;
            color: #333;
            overflow-x: hidden;
        }
        header {
            background: linear-gradient(135deg, var(--dark-color) 0%, var(--primary-color) 100%);
            color: white;
        }
        .navbar {
            padding: 1rem 0;
            transition: all 0.3s;
        }
        .navbar-brand {
            font-size: 1.8rem;
            font-weight: bold;
        }
        .nav-link {
            color: rgba(255,255,255,0.9) !important;
            font-weight: 500;
            margin: 0 0.5rem;
            transition: color 0.3s;
        }
        .nav-link:hover, .nav-link.active {
            color: white !important;
            text-decoration: underline;
        }
        .hero {
            padding: 6rem 0;
            background: url('https://images.unsplash.com/photo-1451187580459-43490279c0fa?ixlib=rb-4.0.3&auto=format&fit=crop&w=2072&q=80') center/cover no-repeat;
            color: white;
            text-shadow: 0 2px 10px rgba(0,0,0,0.5);
            position: relative;
        }
        .hero::before {
            content: '';
            position: absolute;
            top: 0; left: 0;
            width: 100%; height: 100%;
            background: rgba(0, 84, 179, 0.7);
        }
        .hero-content {
            position: relative;
            z-index: 1;
        }
        .section-title {
            font-size: 2.5rem;
            margin-bottom: 2rem;
            color: var(--primary-color);
            border-left: 5px solid var(--secondary-color);
            padding-left: 1rem;
        }
        .card {
            border: none;
            border-radius: 10px;
            overflow: hidden;
            transition: transform 0.3s, box-shadow 0.3s;
            height: 100%;
        }
        .card:hover {
            transform: translateY(-10px);
            box-shadow: 0 15px 30px rgba(0,0,0,0.15);
        }
        .card-img-top {
            height: 200px;
            object-fit: cover;
        }
        .btn-primary {
            background-color: var(--primary-color);
            border-color: var(--primary-color);
            padding: 0.75rem 2rem;
            border-radius: 30px;
            transition: all 0.3s;
        }
        .btn-primary:hover {
            background-color: var(--hover-color);
            border-color: var(--hover-color);
            transform: scale(1.05);
        }
        .friendlink {
            background-color: #f1f8ff;
            padding: 3rem 0;
        }
        .flink {
            display: inline-block;
            margin: 0.5rem 1rem;
            padding: 0.5rem 1rem;
            background: white;
            border-radius: 8px;
            color: var(--dark-color);
            text-decoration: none;
            transition: all 0.3s;
            border: 1px solid #ddd;
        }
        .flink:hover {
            background: var(--primary-color);
            color: white;
            border-color: var(--primary-color);
        }
        footer {
            background-color: var(--dark-color);
            color: white;
            padding: 3rem 0 1.5rem;
        }
        .footer-links a {
            color: #ccc;
            text-decoration: none;
            margin: 0 10px;
        }
        .footer-links a:hover {
            color: white;
            text-decoration: underline;
        }
        .hover-effect {
            transition: all 0.3s ease;
        }
        .hover-effect:hover {
            opacity: 0.9;
            transform: scale(1.02);
        }
        .timeline {
            position: relative;
            padding-left: 2rem;
            border-left: 3px solid var(--secondary-color);
        }
        .timeline-item {
            margin-bottom: 2rem;
            position: relative;
        }
        .timeline-item::before {
            content: '';
            position: absolute;
            left: -2.5rem;
            top: 0.5rem;
            width: 1rem;
            height: 1rem;
            border-radius: 50%;
            background: var(--primary-color);
        }
        @media (max-width: 768px) {
            .section-title {
                font-size: 2rem;
            }
            .hero {
                padding: 4rem 0;
            }
            .navbar-nav {
                text-align: center;
            }
        }