:root {
            --primary-color: #0056a6;
            --secondary-color: #28a745;
            --dark-color: #212529;
            --light-color: #f8f9fa;
            --transition: all 0.3s ease-in-out;
        }
        body {
            font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
            color: var(--dark-color);
            line-height: 1.7;
            overflow-x: hidden;
        }
        h1, h2, h3, h4, h5, h6 {
            font-weight: 700;
            margin-bottom: 1rem;
        }
        .navbar {
            background-color: rgba(255, 255, 255, 0.98) !important;
            box-shadow: 0 2px 15px rgba(0, 0, 0, 0.1);
            transition: var(--transition);
            padding-top: 0.8rem;
            padding-bottom: 0.8rem;
        }
        .navbar-brand {
            font-weight: 800;
            font-size: 1.8rem;
            color: var(--primary-color) !important;
        }
        .navbar-nav .nav-link {
            font-weight: 600;
            color: var(--dark-color) !important;
            padding: 0.5rem 1.2rem !important;
            transition: var(--transition);
            border-radius: 4px;
        }
        .navbar-nav .nav-link:hover, .navbar-nav .nav-link.active {
            color: var(--primary-color) !important;
            background-color: rgba(0, 86, 166, 0.05);
            transform: translateY(-2px);
        }
        .hero-section {
            background: linear-gradient(rgba(0, 0, 0, 0.7), rgba(0, 0, 0, 0.7)), url('https://images.unsplash.com/photo-1486406146926-c627a92ad1ab?ixlib=rb-4.0.3&auto=format&fit=crop&w=1920&q=80');
            background-size: cover;
            background-position: center;
            color: white;
            padding: 10rem 0;
            text-align: center;
        }
        .hero-section h1 {
            font-size: 3.5rem;
            margin-bottom: 1.5rem;
            text-shadow: 2px 2px 5px rgba(0,0,0,0.5);
        }
        .section-title {
            position: relative;
            padding-bottom: 15px;
            margin-bottom: 3rem;
            text-align: center;
            color: var(--primary-color);
        }
        .section-title:after {
            content: '';
            position: absolute;
            width: 80px;
            height: 4px;
            background: var(--secondary-color);
            bottom: 0;
            left: 50%;
            transform: translateX(-50%);
            border-radius: 2px;
        }
        .service-card, .product-card, .case-card {
            border: none;
            border-radius: 10px;
            overflow: hidden;
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
            transition: var(--transition);
            height: 100%;
            background: white;
        }
        .service-card:hover, .product-card:hover, .case-card:hover {
            transform: translateY(-15px);
            box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
        }
        .service-icon, .product-icon {
            font-size: 3rem;
            color: var(--primary-color);
            margin-bottom: 1.5rem;
            display: inline-block;
        }
        .feature-box {
            padding: 2.5rem;
            border-radius: 10px;
            background: white;
            box-shadow: 0 5px 15px rgba(0,0,0,0.05);
            transition: var(--transition);
            height: 100%;
        }
        .feature-box:hover {
            box-shadow: 0 15px 30px rgba(0,0,0,0.1);
        }
        .timeline {
            position: relative;
            padding-left: 2rem;
        }
        .timeline:before {
            content: '';
            position: absolute;
            left: 7px;
            top: 0;
            bottom: 0;
            width: 3px;
            background: var(--primary-color);
            border-radius: 2px;
        }
        .timeline-item {
            position: relative;
            margin-bottom: 2.5rem;
        }
        .timeline-item:before {
            content: '';
            position: absolute;
            left: -2.35rem;
            top: 5px;
            width: 15px;
            height: 15px;
            border-radius: 50%;
            background: var(--secondary-color);
            border: 3px solid white;
            box-shadow: 0 0 0 3px var(--primary-color);
        }
        .contact-info-box {
            background: var(--light-color);
            border-left: 5px solid var(--primary-color);
            padding: 1.5rem;
            margin-bottom: 1.5rem;
            border-radius: 0 8px 8px 0;
        }
        .contact-info-box i {
            color: var(--primary-color);
            font-size: 1.5rem;
            margin-right: 1rem;
        }
        .flink {
            display: inline-block;
            background: var(--light-color);
            padding: 0.8rem 1.5rem;
            margin: 0.5rem;
            border-radius: 50px;
            color: var(--dark-color);
            text-decoration: none;
            font-weight: 500;
            transition: var(--transition);
            border: 1px solid #dee2e6;
        }
        .flink:hover {
            background: var(--primary-color);
            color: white;
            transform: translateY(-3px);
            text-decoration: none;
            border-color: var(--primary-color);
        }
        .footer {
            background-color: var(--dark-color);
            color: rgba(255,255,255,0.8);
            padding-top: 4rem;
        }
        .footer a {
            color: rgba(255,255,255,0.8);
            text-decoration: none;
            transition: color 0.3s;
        }
        .footer a:hover {
            color: white;
            text-decoration: underline;
        }
        .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;
            cursor: pointer;
            opacity: 0;
            visibility: hidden;
            transition: var(--transition);
            box-shadow: 0 5px 15px rgba(0,0,0,0.2);
        }
        .back-to-top.active {
            opacity: 1;
            visibility: visible;
        }
        .back-to-top:hover {
            background-color: var(--secondary-color);
            transform: translateY(-5px);
        }
        .news-card {
            border-left: 4px solid var(--primary-color);
            transition: var(--transition);
        }
        .news-card:hover {
            box-shadow: 0 10px 25px rgba(0,0,0,0.1);
        }
        @media (max-width: 768px) {
            .hero-section h1 {
                font-size: 2.5rem;
            }
            .hero-section {
                padding: 6rem 0;
            }
            .section-title {
                font-size: 1.8rem;
            }
            .navbar-nav .nav-link {
                padding: 0.5rem 0 !important;
            }
        }