:root {
            --primary-color: #2c3e50;
            --secondary-color: #3498db;
            --accent-color: #e74c3c;
            --light-bg: #f8f9fa;
            --dark-text: #333333;
            --light-text: #666666;
            --border-radius: 8px;
            --shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
            --transition: all 0.3s ease;
        }
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        body {
            font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
            color: var(--dark-text);
            line-height: 1.6;
            overflow-x: hidden;
        }
        .container-fluid {
            max-width: 1400px;
        }
        .main-header {
            background-color: white;
            box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
            position: sticky;
            top: 0;
            z-index: 1000;
        }
        .logo {
            font-size: 1.8rem;
            font-weight: 700;
            color: var(--primary-color);
            text-decoration: none;
        }
        .logo span {
            color: var(--accent-color);
        }
        .navbar-nav .nav-link {
            font-weight: 500;
            padding: 0.5rem 1rem;
            color: var(--dark-text);
            transition: var(--transition);
        }
        .navbar-nav .nav-link:hover,
        .navbar-nav .nav-link.active {
            color: var(--secondary-color);
        }
        .navbar-toggler {
            border: none;
            padding: 0.5rem;
        }
        .navbar-toggler:focus {
            box-shadow: none;
        }
        .hero-section {
            background: linear-gradient(rgba(0, 0, 0, 0.7), rgba(0, 0, 0, 0.7)), url('https://images.unsplash.com/photo-1445205170230-053b83016050?ixlib=rb-4.0.3&auto=format&fit=crop&w=1200&q=80');
            background-size: cover;
            background-position: center;
            color: white;
            padding: 120px 0;
            position: relative;
        }
        .hero-title {
            font-size: 3.5rem;
            font-weight: 700;
            margin-bottom: 1.5rem;
        }
        .hero-subtitle {
            font-size: 1.3rem;
            max-width: 700px;
            margin-bottom: 2rem;
            opacity: 0.9;
        }
        .hero-btn {
            background-color: var(--accent-color);
            color: white;
            padding: 0.8rem 2rem;
            border-radius: var(--border-radius);
            text-decoration: none;
            font-weight: 600;
            transition: var(--transition);
            display: inline-block;
        }
        .hero-btn:hover {
            background-color: #c0392b;
            transform: translateY(-3px);
            color: white;
        }
        .card {
            border: none;
            border-radius: var(--border-radius);
            overflow: hidden;
            transition: var(--transition);
            height: 100%;
            box-shadow: var(--shadow);
        }
        .card:hover {
            transform: translateY(-10px);
            box-shadow: 0 12px 24px rgba(0, 0, 0, 0.15);
        }
        .card-img-top {
            height: 220px;
            object-fit: cover;
        }
        .card-title {
            color: var(--primary-color);
            font-weight: 700;
            margin-bottom: 1rem;
        }
        .about-section {
            padding: 100px 0;
            background-color: var(--light-bg);
        }
        .section-title {
            font-size: 2.5rem;
            font-weight: 700;
            color: var(--primary-color);
            margin-bottom: 1rem;
            position: relative;
            display: inline-block;
        }
        .section-title::after {
            content: '';
            position: absolute;
            bottom: -10px;
            left: 0;
            width: 80px;
            height: 4px;
            background-color: var(--accent-color);
        }
        .section-subtitle {
            color: var(--light-text);
            font-size: 1.1rem;
            max-width: 800px;
            margin-bottom: 3rem;
        }
        .about-text {
            font-size: 1.05rem;
            line-height: 1.8;
        }
        .feature-icon {
            width: 60px;
            height: 60px;
            background-color: rgba(52, 152, 219, 0.1);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-bottom: 1.5rem;
        }
        .feature-icon i {
            font-size: 1.8rem;
            color: var(--secondary-color);
        }
        .products-section {
            padding: 100px 0;
        }
        .product-category {
            background-color: var(--light-bg);
            border-radius: var(--border-radius);
            padding: 2rem;
            height: 100%;
            transition: var(--transition);
        }
        .product-category:hover {
            background-color: var(--secondary-color);
            color: white;
        }
        .product-category:hover h4,
        .product-category:hover p {
            color: white;
        }
        .product-category h4 {
            color: var(--primary-color);
            margin-bottom: 1rem;
            transition: var(--transition);
        }
        .services-section {
            padding: 100px 0;
            background-color: var(--light-bg);
        }
        .process-step {
            text-align: center;
            padding: 2rem;
            position: relative;
        }
        .step-number {
            width: 60px;
            height: 60px;
            background-color: var(--secondary-color);
            color: white;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.8rem;
            font-weight: 700;
            margin: 0 auto 1.5rem;
        }
        .news-section {
            padding: 100px 0;
        }
        .news-item {
            border-bottom: 1px solid #eee;
            padding-bottom: 1.5rem;
            margin-bottom: 1.5rem;
        }
        .news-item:last-child {
            border-bottom: none;
        }
        .news-date {
            color: var(--accent-color);
            font-weight: 600;
            margin-bottom: 0.5rem;
        }
        .contact-section {
            padding: 100px 0;
            background-color: var(--light-bg);
        }
        .contact-info {
            background-color: white;
            padding: 2.5rem;
            border-radius: var(--border-radius);
            box-shadow: var(--shadow);
            height: 100%;
        }
        .contact-item {
            display: flex;
            align-items: flex-start;
            margin-bottom: 2rem;
        }
        .contact-icon {
            width: 50px;
            height: 50px;
            background-color: rgba(52, 152, 219, 0.1);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-right: 1rem;
            flex-shrink: 0;
        }
        .contact-icon i {
            color: var(--secondary-color);
            font-size: 1.3rem;
        }
        .friendlink-section {
            padding: 80px 0;
            background-color: #f1f5f9;
        }
        .flink {
            display: inline-block;
            background-color: white;
            padding: 0.8rem 1.5rem;
            margin: 0.5rem;
            border-radius: 50px;
            text-decoration: none;
            color: var(--dark-text);
            font-weight: 500;
            transition: var(--transition);
            border: 1px solid #e2e8f0;
        }
        .flink:hover {
            background-color: var(--secondary-color);
            color: white;
            transform: translateY(-3px);
        }
        .main-footer {
            background-color: var(--primary-color);
            color: white;
            padding: 70px 0 30px;
        }
        .footer-logo {
            font-size: 1.8rem;
            font-weight: 700;
            color: white;
            text-decoration: none;
            margin-bottom: 1.5rem;
            display: inline-block;
        }
        .footer-links h5 {
            color: white;
            margin-bottom: 1.5rem;
            font-size: 1.2rem;
        }
        .footer-links ul {
            list-style: none;
            padding: 0;
        }
        .footer-links li {
            margin-bottom: 0.8rem;
        }
        .footer-links a {
            color: #bdc3c7;
            text-decoration: none;
            transition: var(--transition);
        }
        .footer-links a:hover {
            color: white;
            padding-left: 5px;
        }
        .copyright {
            border-top: 1px solid #34495e;
            padding-top: 2rem;
            margin-top: 3rem;
            text-align: center;
            color: #bdc3c7;
            font-size: 0.9rem;
        }
        @media (max-width: 992px) {
            .hero-title {
                font-size: 2.8rem;
            }
            .section-title {
                font-size: 2.2rem;
            }
        }
        @media (max-width: 768px) {
            .hero-title {
                font-size: 2.2rem;
            }
            .hero-subtitle {
                font-size: 1.1rem;
            }
            .section-title {
                font-size: 2rem;
            }
            .contact-info {
                margin-bottom: 2rem;
            }
        }
        @media (max-width: 576px) {
            .hero-section {
                padding: 80px 0;
            }
            .hero-title {
                font-size: 1.8rem;
            }
            .about-section,
            .products-section,
            .services-section,
            .news-section,
            .contact-section {
                padding: 70px 0;
            }
            .card-img-top {
                height: 180px;
            }
        }
        .fade-in {
            animation: fadeIn 1s ease-in-out;
        }
        @keyframes fadeIn {
            from { opacity: 0; transform: translateY(20px); }
            to { opacity: 1; transform: translateY(0); }
        }
        .btn-primary-custom {
            background-color: var(--secondary-color);
            border-color: var(--secondary-color);
            padding: 0.6rem 1.5rem;
            font-weight: 600;
            transition: var(--transition);
        }
        .btn-primary-custom:hover {
            background-color: #2980b9;
            border-color: #2980b9;
            transform: translateY(-3px);
        }
        .form-control {
            padding: 0.8rem 1rem;
            border-radius: var(--border-radius);
            border: 1px solid #ddd;
            margin-bottom: 1.5rem;
        }
        .form-control:focus {
            border-color: var(--secondary-color);
            box-shadow: 0 0 0 0.25rem rgba(52, 152, 219, 0.25);
        }