:root {
            --primary-color: #0056b3;
            --secondary-color: #f8f9fa;
            --accent-color: #28a745;
            --dark-color: #343a40;
            --light-color: #ffffff;
            --transition-speed: 0.3s;
        }
        body {
            font-family: 'Noto Sans SC', 'Microsoft YaHei', sans-serif;
            line-height: 1.8;
            color: #333;
            overflow-x: hidden;
        }
        .navbar-brand {
            font-weight: 700;
            font-size: 1.8rem;
        }
        .nav-link {
            font-weight: 500;
            margin: 0 5px;
            transition: color var(--transition-speed);
        }
        .nav-link:hover, .nav-link.active {
            color: var(--primary-color) !important;
        }
        .hero-section {
            background: linear-gradient(rgba(0, 84, 180, 0.85), rgba(0, 84, 180, 0.9)), url('https://images.unsplash.com/photo-1486406146926-c627a92ad1ab?ixlib=rb-4.0.3&auto=format&fit=crop&w=1920&q=80') center/cover no-repeat;
            color: white;
            padding: 180px 0 120px;
            position: relative;
        }
        .hero-title {
            font-size: 3.5rem;
            font-weight: 800;
            margin-bottom: 25px;
            text-shadow: 2px 2px 8px rgba(0,0,0,0.3);
        }
        .hero-subtitle {
            font-size: 1.5rem;
            margin-bottom: 40px;
            opacity: 0.95;
        }
        .section-title {
            font-size: 2.5rem;
            font-weight: 700;
            color: var(--dark-color);
            margin-bottom: 50px;
            position: relative;
            padding-bottom: 15px;
        }
        .section-title::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 80px;
            height: 4px;
            background: var(--primary-color);
            border-radius: 2px;
        }
        .section-title.text-center::after {
            left: 50%;
            transform: translateX(-50%);
        }
        .feature-card {
            background: var(--light-color);
            border-radius: 12px;
            padding: 40px 30px;
            height: 100%;
            box-shadow: 0 10px 30px rgba(0,0,0,0.05);
            transition: transform var(--transition-speed), box-shadow var(--transition-speed);
            border: 1px solid #eee;
        }
        .feature-card:hover {
            transform: translateY(-10px);
            box-shadow: 0 15px 40px rgba(0,0,0,0.1);
        }
        .feature-icon {
            font-size: 3rem;
            color: var(--primary-color);
            margin-bottom: 25px;
        }
        .btn-primary {
            background-color: var(--primary-color);
            border-color: var(--primary-color);
            padding: 12px 35px;
            font-weight: 600;
            border-radius: 8px;
            transition: all var(--transition-speed);
        }
        .btn-primary:hover {
            background-color: #004494;
            border-color: #004494;
            transform: translateY(-2px);
        }
        .product-card {
            border: none;
            border-radius: 12px;
            overflow: hidden;
            box-shadow: 0 8px 25px rgba(0,0,0,0.08);
            transition: transform var(--transition-speed);
            margin-bottom: 30px;
            height: 100%;
        }
        .product-card:hover {
            transform: translateY(-8px);
        }
        .product-card img {
            height: 240px;
            object-fit: cover;
            transition: transform 0.5s;
        }
        .product-card:hover img {
            transform: scale(1.05);
        }
        .news-card {
            border-left: 4px solid var(--primary-color);
            padding-left: 20px;
            margin-bottom: 30px;
        }
        .news-date {
            color: var(--accent-color);
            font-weight: 600;
        }
        .contact-info-box {
            background: var(--secondary-color);
            border-radius: 12px;
            padding: 30px;
            height: 100%;
            border-left: 5px solid var(--primary-color);
        }
        footer {
            background-color: var(--dark-color);
            color: #ccc;
            padding-top: 70px;
        }
        footer a {
            color: #ddd;
            text-decoration: none;
            transition: color var(--transition-speed);
        }
        footer a:hover {
            color: var(--light-color);
        }
        .flink {
            display: inline-block;
            background: rgba(255,255,255,0.1);
            padding: 8px 20px;
            border-radius: 6px;
            margin: 5px 10px 5px 0;
            transition: all var(--transition-speed);
        }
        .flink:hover {
            background: var(--primary-color);
            transform: translateY(-3px);
        }
        .friendlink-section {
            background: rgba(0,0,0,0.05);
            padding: 30px;
            border-radius: 12px;
        }
        .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;
            font-size: 1.5rem;
            z-index: 1000;
            opacity: 0;
            visibility: hidden;
            transition: all 0.4s;
        }
        .back-to-top.active {
            opacity: 1;
            visibility: visible;
        }
        @media (max-width: 768px) {
            .hero-title {
                font-size: 2.5rem;
            }
            .hero-subtitle {
                font-size: 1.2rem;
            }
            .section-title {
                font-size: 2rem;
            }
        }