:root {
            --primary-color: #1a56db;
            --secondary-color: #0e9f6e;
            --dark-color: #1f2937;
            --light-color: #f9fafb;
            --gray-color: #6b7280;
        }
        body {
            font-family: 'Microsoft YaHei', 'Segoe UI', sans-serif;
            line-height: 1.6;
            color: var(--dark-color);
            overflow-x: hidden;
        }
        .navbar {
            background-color: rgba(255, 255, 255, 0.95);
            box-shadow: 0 2px 15px rgba(0, 0, 0, 0.08);
            padding: 15px 0;
            transition: all 0.3s ease;
        }
        .navbar-brand {
            font-weight: 700;
            font-size: 1.8rem;
            color: var(--primary-color);
        }
        .nav-link {
            font-weight: 500;
            margin: 0 8px;
            color: var(--dark-color);
            transition: color 0.3s;
        }
        .nav-link:hover {
            color: var(--primary-color);
        }
        .hero-section {
            background: linear-gradient(135deg, rgba(26, 86, 219, 0.9) 0%, rgba(30, 64, 175, 0.9) 100%), url('https://images.unsplash.com/photo-1518709268805-4e9042af2176?ixlib=rb-4.0.3&auto=format&fit=crop&w=1920&q=80');
            background-size: cover;
            background-position: center;
            color: white;
            padding: 120px 0;
            position: relative;
        }
        .section-title {
            position: relative;
            padding-bottom: 15px;
            margin-bottom: 50px;
            font-weight: 700;
        }
        .section-title:after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 60px;
            height: 4px;
            background-color: var(--primary-color);
        }
        .text-center .section-title:after {
            left: 50%;
            transform: translateX(-50%);
        }
        .card {
            border: none;
            border-radius: 12px;
            box-shadow: 0 5px 20px rgba(0, 0, 0, 0.08);
            transition: transform 0.3s, box-shadow 0.3s;
            height: 100%;
        }
        .card:hover {
            transform: translateY(-10px);
            box-shadow: 0 15px 30px rgba(0, 0, 0, 0.12);
        }
        .service-icon {
            width: 70px;
            height: 70px;
            background: linear-gradient(135deg, var(--primary-color), #3b82f6);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-bottom: 20px;
            color: white;
            font-size: 1.8rem;
        }
        .btn-primary {
            background-color: var(--primary-color);
            border-color: var(--primary-color);
            padding: 10px 25px;
            border-radius: 6px;
            font-weight: 500;
            transition: all 0.3s;
        }
        .btn-primary:hover {
            background-color: #1e40af;
            border-color: #1e40af;
            transform: translateY(-2px);
        }
        .btn-outline-primary {
            color: var(--primary-color);
            border-color: var(--primary-color);
            padding: 10px 25px;
            border-radius: 6px;
            font-weight: 500;
            transition: all 0.3s;
        }
        .btn-outline-primary:hover {
            background-color: var(--primary-color);
            border-color: var(--primary-color);
            transform: translateY(-2px);
        }
        .footer {
            background-color: var(--dark-color);
            color: white;
            padding: 70px 0 30px;
        }
        .footer h5 {
            margin-bottom: 25px;
            position: relative;
            padding-bottom: 10px;
        }
        .footer h5:after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 40px;
            height: 3px;
            background-color: var(--primary-color);
        }
        .footer a {
            color: #d1d5db;
            text-decoration: none;
            transition: color 0.3s;
        }
        .footer a:hover {
            color: white;
        }
        .copyright {
            border-top: 1px solid #374151;
            padding-top: 20px;
            margin-top: 50px;
            color: #9ca3af;
            font-size: 0.9rem;
        }
        .flink {
            display: inline-block;
            background-color: white;
            padding: 8px 20px;
            border-radius: 6px;
            margin: 5px;
            color: var(--dark-color);
            font-weight: 500;
            transition: all 0.3s;
            text-decoration: none;
            box-shadow: 0 2px 5px rgba(0, 0, 0, 0.05);
        }
        .flink:hover {
            background-color: var(--primary-color);
            color: white;
            transform: translateY(-3px);
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
        }
        .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: all 0.3s;
        }
        .back-to-top.active {
            opacity: 1;
            visibility: visible;
        }
        .back-to-top:hover {
            background-color: #1e40af;
            transform: translateY(-5px);
        }
        .timeline-item {
            position: relative;
            padding-left: 30px;
            margin-bottom: 40px;
        }
        .timeline-item:before {
            content: '';
            position: absolute;
            left: 0;
            top: 5px;
            width: 15px;
            height: 15px;
            border-radius: 50%;
            background-color: var(--primary-color);
        }
        .timeline-item:after {
            content: '';
            position: absolute;
            left: 7px;
            top: 20px;
            width: 1px;
            height: calc(100% + 20px);
            background-color: #e5e7eb;
        }
        .timeline-item:last-child:after {
            display: none;
        }
        .form-control, .form-select {
            padding: 12px 15px;
            border-radius: 6px;
            border: 1px solid #d1d5db;
        }
        .form-control:focus, .form-select:focus {
            border-color: var(--primary-color);
            box-shadow: 0 0 0 3px rgba(26, 86, 219, 0.1);
        }
        @media (max-width: 768px) {
            .hero-section {
                padding: 80px 0;
            }
            .section-title {
                font-size: 1.8rem;
            }
            .navbar-brand {
                font-size: 1.5rem;
            }
        }