:root {
            --primary-color: #1a365d;
            --secondary-color: #2d7d9a;
            --accent-color: #e63946;
            --light-color: #f8f9fa;
            --dark-color: #212529;
            --transition: all 0.3s ease;
        }
        body {
            font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
            color: #333;
            overflow-x: hidden;
        }
        .navbar-brand {
            font-weight: 700;
            font-size: 1.8rem;
            color: var(--primary-color) !important;
        }
        .navbar-nav .nav-link {
            font-weight: 500;
            margin: 0 0.5rem;
            transition: var(--transition);
        }
        .navbar-nav .nav-link:hover,
        .navbar-nav .nav-link.active {
            color: var(--accent-color) !important;
        }
        .hero-section {
            background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
            color: white;
            padding: 8rem 0;
            position: relative;
            overflow: hidden;
        }
        .hero-section h1 {
            font-size: 3.5rem;
            font-weight: 800;
            margin-bottom: 1.5rem;
            text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
        }
        .hero-section .lead {
            font-size: 1.5rem;
            margin-bottom: 2rem;
        }
        .btn-primary-custom {
            background-color: var(--accent-color);
            border-color: var(--accent-color);
            color: white;
            padding: 0.8rem 2rem;
            font-weight: 600;
            border-radius: 50px;
            transition: var(--transition);
        }
        .btn-primary-custom:hover {
            background-color: #c1121f;
            border-color: #c1121f;
            transform: translateY(-3px);
            box-shadow: 0 10px 20px rgba(0,0,0,0.2);
        }
        .section-title {
            text-align: center;
            margin-bottom: 4rem;
            position: relative;
            color: var(--primary-color);
        }
        .section-title h2 {
            font-size: 2.8rem;
            font-weight: 700;
            display: inline-block;
            padding-bottom: 1rem;
        }
        .section-title h2::after {
            content: '';
            position: absolute;
            width: 80px;
            height: 4px;
            background: var(--accent-color);
            bottom: 0;
            left: 50%;
            transform: translateX(-50%);
            border-radius: 2px;
        }
        .service-card, .product-card, .case-card, .news-card {
            border: none;
            border-radius: 15px;
            overflow: hidden;
            transition: var(--transition);
            height: 100%;
            box-shadow: 0 5px 15px rgba(0,0,0,0.08);
            margin-bottom: 2rem;
        }
        .service-card:hover, .product-card:hover, .case-card:hover, .news-card:hover {
            transform: translateY(-10px);
            box-shadow: 0 15px 30px rgba(0,0,0,0.15);
        }
        .service-icon, .product-icon {
            background: linear-gradient(45deg, var(--primary-color), var(--secondary-color));
            width: 80px;
            height: 80px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 2rem auto 1.5rem;
            color: white;
            font-size: 2rem;
        }
        .card-title {
            color: var(--primary-color);
            font-weight: 700;
            margin-bottom: 1rem;
        }
        .stats-section {
            background-color: #f0f8ff;
            padding: 5rem 0;
        }
        .stat-item {
            text-align: center;
            padding: 2rem;
        }
        .stat-number {
            font-size: 3.5rem;
            font-weight: 800;
            color: var(--accent-color);
            line-height: 1;
        }
        .stat-label {
            font-size: 1.2rem;
            color: var(--dark-color);
            margin-top: 1rem;
            font-weight: 600;
        }
        .team-member {
            text-align: center;
            margin-bottom: 2rem;
        }
        .team-member img {
            width: 180px;
            height: 180px;
            object-fit: cover;
            border-radius: 50%;
            border: 5px solid #e9ecef;
            margin-bottom: 1.5rem;
            transition: var(--transition);
        }
        .team-member:hover img {
            border-color: var(--secondary-color);
        }
        footer {
            background-color: var(--primary-color);
            color: white;
            padding-top: 4rem;
        }
        .footer-links h5 {
            color: #fff;
            margin-bottom: 1.5rem;
            font-weight: 600;
        }
        .footer-links ul {
            list-style: none;
            padding-left: 0;
        }
        .footer-links li {
            margin-bottom: 0.8rem;
        }
        .footer-links a {
            color: #b8d4ff;
            text-decoration: none;
            transition: var(--transition);
        }
        .footer-links a:hover {
            color: white;
            padding-left: 5px;
        }
        .copyright {
            border-top: 1px solid #2d4a80;
            padding: 1.5rem 0;
            margin-top: 3rem;
            text-align: center;
            color: #b8d4ff;
            font-size: 0.9rem;
        }
        .flink {
            display: inline-block;
            background: rgba(255,255,255,0.1);
            color: #b8d4ff;
            padding: 0.5rem 1.5rem;
            margin: 0.5rem;
            border-radius: 30px;
            text-decoration: none;
            transition: var(--transition);
            border: 1px solid transparent;
        }
        .flink:hover {
            background: var(--accent-color);
            color: white;
            border-color: var(--accent-color);
        }
        .contact-info i {
            color: var(--secondary-color);
            margin-right: 1rem;
            width: 20px;
        }
        .form-control:focus {
            border-color: var(--secondary-color);
            box-shadow: 0 0 0 0.25rem rgba(45, 125, 154, 0.25);
        }
        .news-card .card-img-top {
            height: 220px;
            object-fit: cover;
        }
        .news-date {
            color: var(--accent-color);
            font-size: 0.9rem;
            font-weight: 600;
        }
        .back-to-top {
            position: fixed;
            bottom: 30px;
            right: 30px;
            width: 50px;
            height: 50px;
            background-color: var(--accent-color);
            color: white;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.2rem;
            text-decoration: none;
            opacity: 0;
            visibility: hidden;
            transition: var(--transition);
            z-index: 1000;
        }
        .back-to-top.active {
            opacity: 1;
            visibility: visible;
        }
        .back-to-top:hover {
            background-color: #c1121f;
            color: white;
        }
        @media (max-width: 768px) {
            .hero-section h1 {
                font-size: 2.5rem;
            }
            .hero-section .lead {
                font-size: 1.2rem;
            }
            .section-title h2 {
                font-size: 2.2rem;
            }
            .stat-number {
                font-size: 2.8rem;
            }
        }