:root {
            --primary-color: #0056b3;
            --secondary-color: #17a2b8;
            --dark-color: #343a40;
            --light-color: #f8f9fa;
            --accent-color: #28a745;
        }
        body {
            font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
            color: #333;
            overflow-x: hidden;
        }
        .navbar-brand {
            font-weight: 700;
            font-size: 1.8rem;
        }
        .hero-section {
            background: linear-gradient(rgba(0, 84, 179, 0.85), rgba(0, 84, 179, 0.9)), url('https://images.unsplash.com/photo-1635070041078-e363dbe005cb?ixlib=rb-4.0.3&auto=format&fit=crop&w=2070&q=80') center/cover no-repeat;
            color: white;
            padding: 8rem 0;
        }
        .section-title {
            position: relative;
            padding-bottom: 15px;
            margin-bottom: 3rem;
            text-align: center;
            color: var(--dark-color);
        }
        .section-title:after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 50%;
            transform: translateX(-50%);
            width: 80px;
            height: 4px;
            background: var(--secondary-color);
        }
        .card-hover {
            transition: transform 0.3s ease, box-shadow 0.3s ease;
            border: none;
            border-radius: 10px;
            overflow: hidden;
        }
        .card-hover:hover {
            transform: translateY(-10px);
            box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
        }
        .product-card .card-img-top {
            height: 220px;
            object-fit: cover;
            transition: transform 0.5s ease;
        }
        .product-card:hover .card-img-top {
            transform: scale(1.05);
        }
        .flink {
            display: inline-block;
            padding: 8px 20px;
            margin: 5px;
            background: var(--light-color);
            border-radius: 50px;
            text-decoration: none;
            color: var(--dark-color);
            border: 1px solid #dee2e6;
            transition: all 0.3s ease;
        }
        .flink:hover {
            background: var(--primary-color);
            color: white;
            transform: translateY(-3px);
        }
        footer {
            background: var(--dark-color);
            color: var(--light-color);
        }
        .social-icon {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            width: 40px;
            height: 40px;
            border-radius: 50%;
            background: rgba(255, 255, 255, 0.1);
            color: white;
            margin-right: 10px;
            transition: all 0.3s ease;
        }
        .social-icon:hover {
            background: var(--primary-color);
            transform: scale(1.1);
        }
        .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;
            text-decoration: none;
            opacity: 0;
            transition: opacity 0.3s;
            z-index: 1000;
        }
        .back-to-top.show {
            opacity: 1;
        }
        .news-item {
            border-left: 4px solid var(--secondary-color);
            padding-left: 15px;
            margin-bottom: 25px;
        }
        .timeline {
            position: relative;
            padding-left: 30px;
        }
        .timeline:before {
            content: '';
            position: absolute;
            left: 0;
            top: 0;
            bottom: 0;
            width: 2px;
            background: var(--secondary-color);
        }
        .timeline-item {
            position: relative;
            margin-bottom: 30px;
        }
        .timeline-item:before {
            content: '';
            position: absolute;
            left: -36px;
            top: 5px;
            width: 12px;
            height: 12px;
            border-radius: 50%;
            background: var(--primary-color);
            border: 3px solid white;
            box-shadow: 0 0 0 3px var(--secondary-color);
        }
        .contact-info-box {
            background: white;
            padding: 30px;
            border-radius: 10px;
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
            height: 100%;
            border-top: 4px solid var(--secondary-color);
        }
        @media (max-width: 768px) {
            .hero-section {
                padding: 5rem 0;
            }
            .display-4 {
                font-size: 2.5rem;
            }
        }