:root {
            --primary-color: #1a4a8f;
            --secondary-color: #e8b417;
            --accent-color: #2c662d;
            --light-bg: #f8f9fa;
            --dark-text: #212529;
            --transition: all 0.3s ease;
        }
        body {
            font-family: "Microsoft YaHei", "PingFang SC", sans-serif;
            color: var(--dark-text);
            overflow-x: hidden;
        }
        .hero-section {
            background: linear-gradient(rgba(0, 0, 0, 0.7), rgba(0, 0, 0, 0.7)), url('https://images.unsplash.com/photo-1497366754035-f200968a6e72?ixlib=rb-4.0.3&auto=format&fit=crop&w=1920&q=80') center/cover no-repeat;
            color: white;
            padding: 160px 0 100px;
            min-height: 90vh;
            display: flex;
            align-items: center;
        }
        .navbar {
            background-color: rgba(255, 255, 255, 0.98) !important;
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
            padding-top: 0.8rem;
            padding-bottom: 0.8rem;
            transition: var(--transition);
        }
        .navbar-brand {
            font-weight: 700;
            color: var(--primary-color) !important;
            font-size: 1.8rem;
        }
        .nav-link {
            font-weight: 500;
            margin: 0 0.5rem;
            color: var(--dark-text) !important;
            transition: var(--transition);
            position: relative;
        }
        .nav-link:hover, .nav-link.active {
            color: var(--primary-color) !important;
        }
        .nav-link:hover::after {
            width: 100%;
        }
        .nav-link::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 0;
            height: 2px;
            background-color: var(--primary-color);
            transition: var(--transition);
        }
        .section-title {
            color: var(--primary-color);
            font-weight: 700;
            margin-bottom: 3rem;
            position: relative;
            padding-bottom: 1rem;
        }
        .section-title::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 60px;
            height: 4px;
            background-color: var(--secondary-color);
        }
        .card-hover {
            transition: var(--transition);
            border: none;
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
            height: 100%;
        }
        .card-hover:hover {
            transform: translateY(-10px);
            box-shadow: 0 15px 30px rgba(0, 0, 0, 0.1);
        }
        .btn-primary-custom {
            background-color: var(--primary-color);
            border-color: var(--primary-color);
            color: white;
            padding: 0.75rem 2rem;
            font-weight: 600;
            border-radius: 4px;
            transition: var(--transition);
        }
        .btn-primary-custom:hover {
            background-color: #153b75;
            border-color: #153b75;
            transform: scale(1.05);
        }
        .icon-box {
            width: 70px;
            height: 70px;
            background-color: rgba(26, 74, 143, 0.1);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-bottom: 1.5rem;
            color: var(--primary-color);
            font-size: 1.8rem;
        }
        .timeline-item {
            position: relative;
            padding-left: 3rem;
            margin-bottom: 3rem;
        }
        .timeline-item::before {
            content: '';
            position: absolute;
            left: 7px;
            top: 0;
            width: 2px;
            height: 100%;
            background-color: var(--primary-color);
        }
        .timeline-dot {
            position: absolute;
            left: 0;
            top: 0;
            width: 16px;
            height: 16px;
            border-radius: 50%;
            background-color: var(--secondary-color);
            border: 3px solid var(--primary-color);
        }
        footer {
            background-color: #1a2a3a;
            color: #ccc;
        }
        footer a {
            color: #ccc;
            text-decoration: none;
            transition: var(--transition);
        }
        footer a:hover {
            color: white;
            text-decoration: underline;
        }
        .flink {
            display: inline-block;
            background-color: rgba(255, 255, 255, 0.1);
            padding: 0.5rem 1.2rem;
            margin: 0.3rem;
            border-radius: 30px;
            font-size: 0.9rem;
            transition: var(--transition);
        }
        .flink:hover {
            background-color: var(--secondary-color);
            color: var(--dark-text);
            transform: translateY(-3px);
        }
        .back-to-top {
            position: fixed;
            bottom: 30px;
            right: 30px;
            width: 50px;
            height: 50px;
            background-color: var(--primary-color);
            color: white;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.2rem;
            z-index: 1000;
            opacity: 0;
            visibility: hidden;
            transition: var(--transition);
        }
        .back-to-top.active {
            opacity: 1;
            visibility: visible;
        }
        @media (max-width: 768px) {
            .hero-section {
                padding: 120px 0 60px;
                text-align: center;
            }
            .section-title {
                text-align: center;
            }
            .section-title::after {
                left: 50%;
                transform: translateX(-50%);
            }
        }