:root {
            --primary-color: #1a365d;
            --secondary-color: #c53030;
            --accent-color: #f6ad55;
            --light-color: #f7fafc;
            --dark-color: #2d3748;
            --transition: all 0.3s ease;
        }
        body {
            font-family: 'Microsoft YaHei', 'Segoe UI', sans-serif;
            color: var(--dark-color);
            overflow-x: hidden;
        }
        .navbar {
            background-color: rgba(26, 54, 93, 0.95);
            backdrop-filter: blur(10px);
            padding: 1rem 0;
            transition: var(--transition);
            box-shadow: 0 4px 12px rgba(0,0,0,0.1);
        }
        .navbar-brand {
            font-weight: 700;
            font-size: 1.8rem;
            color: white !important;
        }
        .nav-link {
            color: rgba(255,255,255,0.9) !important;
            font-weight: 500;
            margin: 0 0.5rem;
            transition: var(--transition);
            position: relative;
        }
        .nav-link:hover, .nav-link.active {
            color: var(--accent-color) !important;
        }
        .nav-link::after {
            content: '';
            position: absolute;
            width: 0;
            height: 2px;
            background: var(--accent-color);
            left: 50%;
            bottom: 0;
            transition: var(--transition);
        }
        .nav-link:hover::after, .nav-link.active::after {
            width: 80%;
            left: 10%;
        }
        .hero-section {
            background: linear-gradient(rgba(26, 54, 93, 0.8), rgba(26, 54, 93, 0.9)), url('https://images.unsplash.com/photo-1556742049-0cfed4f6a45d?ixlib=rb-4.0.3&auto=format&fit=crop&w=1920&q=80');
            background-size: cover;
            background-position: center;
            color: white;
            padding: 8rem 0;
            margin-top: 76px;
        }
        .section-title {
            position: relative;
            margin-bottom: 3rem;
            padding-bottom: 1rem;
            text-align: center;
        }
        .section-title::after {
            content: '';
            position: absolute;
            width: 80px;
            height: 4px;
            background: var(--secondary-color);
            bottom: 0;
            left: 50%;
            transform: translateX(-50%);
        }
        .card-hover {
            transition: var(--transition);
            border: none;
            box-shadow: 0 6px 15px rgba(0,0,0,0.08);
            height: 100%;
        }
        .card-hover:hover {
            transform: translateY(-10px);
            box-shadow: 0 12px 25px rgba(0,0,0,0.15);
        }
        .icon-box {
            width: 80px;
            height: 80px;
            background: var(--primary-color);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0 auto 1.5rem;
            transition: var(--transition);
        }
        .service-card:hover .icon-box {
            background: var(--secondary-color);
            transform: rotateY(180deg);
        }
        .icon-box i {
            font-size: 2rem;
            color: white;
        }
        .btn-primary-custom {
            background: var(--primary-color);
            border: none;
            padding: 0.8rem 2rem;
            border-radius: 4px;
            color: white;
            font-weight: 600;
            transition: var(--transition);
        }
        .btn-primary-custom:hover {
            background: var(--secondary-color);
            transform: translateY(-3px);
            box-shadow: 0 6px 12px rgba(197, 48, 48, 0.2);
        }
        .footer {
            background: var(--primary-color);
            color: white;
            padding: 4rem 0 2rem;
        }
        .footer a {
            color: rgba(255,255,255,0.8);
            text-decoration: none;
            transition: var(--transition);
        }
        .footer a:hover {
            color: var(--accent-color);
            padding-left: 5px;
        }
        .copyright {
            background: rgba(0,0,0,0.2);
            padding: 1.5rem 0;
            margin-top: 3rem;
            border-top: 1px solid rgba(255,255,255,0.1);
        }
        .flink {
            display: inline-block;
            background: rgba(255,255,255,0.1);
            color: white;
            padding: 0.5rem 1.5rem;
            margin: 0.5rem;
            border-radius: 4px;
            transition: var(--transition);
            text-decoration: none;
        }
        .flink:hover {
            background: var(--accent-color);
            color: var(--dark-color);
            transform: translateY(-3px);
        }
        .product-img {
            height: 200px;
            object-fit: cover;
            transition: var(--transition);
        }
        .product-card:hover .product-img {
            transform: scale(1.05);
        }
        .contact-info {
            background: var(--light-color);
            border-radius: 8px;
            padding: 2rem;
            box-shadow: 0 5px 15px rgba(0,0,0,0.05);
        }
        .contact-icon {
            width: 60px;
            height: 60px;
            background: var(--primary-color);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-right: 1rem;
        }
        .contact-icon i {
            color: white;
            font-size: 1.5rem;
        }
        .back-to-top {
            position: fixed;
            bottom: 30px;
            right: 30px;
            width: 50px;
            height: 50px;
            background: var(--primary-color);
            color: white;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            cursor: pointer;
            opacity: 0;
            visibility: hidden;
            transition: var(--transition);
            z-index: 1000;
        }
        .back-to-top.active {
            opacity: 1;
            visibility: visible;
        }
        .back-to-top:hover {
            background: var(--secondary-color);
            transform: translateY(-5px);
        }
        .news-card {
            border-left: 4px solid var(--primary-color);
            transition: var(--transition);
        }
        .news-card:hover {
            border-left-color: var(--secondary-color);
            box-shadow: 0 8px 20px rgba(0,0,0,0.1);
        }
        @media (max-width: 768px) {
            .hero-section {
                padding: 5rem 0;
                text-align: center;
            }
            .section-title {
                font-size: 1.8rem;
            }
            .navbar-nav {
                text-align: center;
                padding-top: 1rem;
            }
            .contact-info {
                margin-bottom: 2rem;
            }
        }