:root {
            --primary-color: #1a5f7a;
            --secondary-color: #57cc99;
            --accent-color: #ff9a3c;
            --dark-color: #2d3047;
            --light-color: #f8f9fa;
        }
        body {
            font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
            color: #333;
            line-height: 1.6;
        }
        .navbar {
            background-color: rgba(255, 255, 255, 0.95);
            box-shadow: 0 2px 15px rgba(0, 0, 0, 0.1);
            padding: 1rem 0;
            transition: all 0.3s ease;
        }
        .navbar-brand {
            font-weight: 700;
            color: var(--primary-color);
            font-size: 1.8rem;
        }
        .nav-link {
            color: var(--dark-color);
            font-weight: 500;
            margin: 0 0.5rem;
            transition: color 0.3s;
        }
        .nav-link:hover {
            color: var(--primary-color);
        }
        .hero-section {
            background: linear-gradient(135deg, var(--primary-color) 0%, #2a8cad 100%);
            color: white;
            padding: 8rem 0 6rem;
            position: relative;
            overflow: hidden;
        }
        .hero-section h1 {
            font-size: 3.5rem;
            font-weight: 700;
            margin-bottom: 1.5rem;
        }
        .section-title {
            color: var(--primary-color);
            font-weight: 700;
            margin-bottom: 3rem;
            position: relative;
            padding-bottom: 15px;
        }
        .section-title::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 80px;
            height: 4px;
            background-color: var(--secondary-color);
        }
        .service-card {
            border: none;
            border-radius: 12px;
            overflow: hidden;
            transition: transform 0.4s, box-shadow 0.4s;
            height: 100%;
            background: white;
            box-shadow: 0 5px 20px rgba(0, 0, 0, 0.08);
        }
        .service-card:hover {
            transform: translateY(-10px);
            box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
        }
        .service-icon {
            width: 80px;
            height: 80px;
            background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0 auto 1.5rem;
            color: white;
            font-size: 2rem;
        }
        .btn-primary {
            background-color: var(--primary-color);
            border-color: var(--primary-color);
            padding: 0.75rem 2rem;
            font-weight: 600;
            border-radius: 50px;
            transition: all 0.3s;
        }
        .btn-primary:hover {
            background-color: #144a5f;
            border-color: #144a5f;
            transform: translateY(-3px);
            box-shadow: 0 5px 15px rgba(26, 95, 122, 0.3);
        }
        .feature-box {
            padding: 2.5rem;
            border-radius: 12px;
            background: white;
            height: 100%;
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
            transition: transform 0.3s;
        }
        .feature-box:hover {
            transform: translateY(-5px);
        }
        .stat-number {
            font-size: 3rem;
            font-weight: 700;
            color: var(--primary-color);
            line-height: 1;
        }
        .testimonial-card {
            background: white;
            border-radius: 12px;
            padding: 2rem;
            box-shadow: 0 5px 20px rgba(0, 0, 0, 0.08);
            height: 100%;
            border-left: 5px solid var(--secondary-color);
        }
        .footer {
            background-color: var(--dark-color);
            color: white;
            padding-top: 4rem;
        }
        .footer a {
            color: #ddd;
            text-decoration: none;
            transition: color 0.3s;
        }
        .footer a:hover {
            color: white;
            text-decoration: underline;
        }
        .friendlink .flink {
            display: inline-block;
            background: rgba(255, 255, 255, 0.1);
            padding: 0.5rem 1.5rem;
            border-radius: 50px;
            margin: 0.5rem;
            color: white;
            text-decoration: none;
            transition: all 0.3s;
            border: 1px solid transparent;
        }
        .friendlink .flink:hover {
            background: rgba(255, 255, 255, 0.2);
            border-color: var(--secondary-color);
            transform: translateY(-3px);
        }
        .contact-info i {
            width: 40px;
            color: var(--secondary-color);
        }
        .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: 1.5rem;
            text-decoration: none;
            opacity: 0;
            visibility: hidden;
            transition: all 0.3s;
            z-index: 1000;
        }
        .back-to-top.active {
            opacity: 1;
            visibility: visible;
        }
        .back-to-top:hover {
            background-color: var(--secondary-color);
            color: white;
        }
        @media (max-width: 768px) {
            .hero-section h1 {
                font-size: 2.5rem;
            }
            .section-title {
                font-size: 1.8rem;
            }
        }