:root {
            --primary-color: #0056b3;
            --secondary-color: #17a2b8;
            --accent-color: #28a745;
            --dark-color: #343a40;
            --light-color: #f8f9fa;
        }
        body {
            font-family: 'Microsoft YaHei', 'Segoe UI', sans-serif;
            color: #333;
            line-height: 1.6;
        }
        header {
            background: linear-gradient(rgba(0, 84, 180, 0.9), rgba(0, 84, 180, 0.8)), url('https://images.unsplash.com/photo-1556909114-f6e7ad7d3136?ixlib=rb-4.0.3&auto=format&fit=crop&w=1600&q=80') center/cover no-repeat;
            color: white;
        }
        .navbar-brand img {
            height: 50px;
        }
        .hero-section {
            padding: 150px 0;
        }
        .hero-section h1 {
            font-size: 3.5rem;
            font-weight: bold;
            text-shadow: 2px 2px 4px rgba(0,0,0,0.5);
        }
        .section-title {
            position: relative;
            padding-bottom: 15px;
            margin-bottom: 40px;
            color: var(--primary-color);
        }
        .section-title:after {
            content: '';
            position: absolute;
            left: 50%;
            bottom: 0;
            transform: translateX(-50%);
            width: 80px;
            height: 3px;
            background: var(--secondary-color);
        }
        .card {
            border: none;
            box-shadow: 0 5px 15px rgba(0,0,0,0.1);
            transition: transform 0.3s ease;
            height: 100%;
        }
        .card:hover {
            transform: translateY(-10px);
        }
        .card-img-top {
            height: 220px;
            object-fit: cover;
        }
        .product-card .card-img-top {
            height: 180px;
        }
        .btn-primary {
            background-color: var(--primary-color);
            border-color: var(--primary-color);
            padding: 10px 25px;
        }
        .btn-primary:hover {
            background-color: #004494;
            border-color: #004494;
        }
        .hover-shadow:hover {
            box-shadow: 0 10px 20px rgba(0,0,0,0.2);
        }
        .flink {
            display: inline-block;
            padding: 8px 15px;
            margin: 5px;
            background: var(--light-color);
            border-radius: 5px;
            color: var(--dark-color);
            text-decoration: none;
            transition: all 0.3s;
        }
        .flink:hover {
            background: var(--primary-color);
            color: white;
            transform: scale(1.05);
        }
        footer {
            background-color: var(--dark-color);
            color: var(--light-color);
        }
        footer a {
            color: #adb5bd;
            text-decoration: none;
        }
        footer a:hover {
            color: white;
            text-decoration: underline;
        }
        .social-icons a {
            font-size: 1.5rem;
            margin: 0 10px;
            color: #ccc;
            transition: color 0.3s;
        }
        .social-icons a:hover {
            color: var(--secondary-color);
        }
        .sticky-nav {
            position: sticky;
            top: 0;
            z-index: 1020;
            background-color: rgba(255, 255, 255, 0.95);
            box-shadow: 0 2px 10px rgba(0,0,0,0.1);
        }
        .news-item {
            border-left: 4px solid var(--secondary-color);
            padding-left: 15px;
            margin-bottom: 25px;
        }
        .contact-info i {
            width: 30px;
            color: var(--primary-color);
        }
        @media (max-width: 768px) {
            .hero-section h1 {
                font-size: 2.5rem;
            }
            .hero-section {
                padding: 100px 0;
            }
            .section-title {
                font-size: 1.8rem;
            }
        }