:root {
            --primary-color: #0056b3;
            --secondary-color: #333333;
            --accent-color: #e30613;
            --light-bg: #f8f9fa;
            --dark-bg: #212529;
            --transition: all 0.3s ease;
        }
        body {
            font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
            color: var(--secondary-color);
            line-height: 1.6;
            overflow-x: hidden;
        }
        h1, h2, h3, h4, h5 {
            font-weight: 700;
            color: var(--primary-color);
        }
        .section-header {
            text-align: center;
            margin-bottom: 3rem;
            padding-bottom: 1rem;
            border-bottom: 3px solid var(--accent-color);
            position: relative;
        }
        .section-header:after {
            content: '';
            position: absolute;
            width: 60px;
            height: 3px;
            background: var(--primary-color);
            bottom: -3px;
            left: 50%;
            transform: translateX(-50%);
        }
        .navbar {
            background-color: rgba(255, 255, 255, 0.95) !important;
            box-shadow: 0 2px 10px rgba(0,0,0,0.1);
            transition: var(--transition);
            padding-top: 0.8rem;
            padding-bottom: 0.8rem;
        }
        .navbar-brand {
            font-weight: 800;
            font-size: 1.8rem;
            color: var(--primary-color) !important;
        }
        .navbar-brand span {
            color: var(--accent-color);
        }
        .nav-link {
            font-weight: 600;
            margin: 0 0.5rem;
            color: var(--secondary-color) !important;
            transition: var(--transition);
            position: relative;
        }
        .nav-link:hover, .nav-link.active {
            color: var(--primary-color) !important;
        }
        .nav-link:hover:after {
            width: 100%;
        }
        .hero-section {
            background: linear-gradient(rgba(0, 30, 60, 0.85), rgba(0, 30, 60, 0.9)), url('https://images.unsplash.com/photo-1581094794329-c8112a89af12?ixlib=rb-4.0.3&auto=format&fit=crop&w=2070&q=80') center/cover no-repeat;
            color: white;
            padding: 10rem 0 8rem;
            margin-top: 76px;
        }
        .hero-title {
            font-size: 3.2rem;
            font-weight: 800;
            margin-bottom: 1.5rem;
            text-shadow: 2px 2px 5px rgba(0,0,0,0.5);
        }
        .hero-subtitle {
            font-size: 1.3rem;
            margin-bottom: 2.5rem;
            opacity: 0.9;
        }
        .btn-primary-custom {
            background-color: var(--accent-color);
            border-color: var(--accent-color);
            color: white;
            padding: 0.8rem 2.2rem;
            font-weight: 600;
            border-radius: 30px;
            transition: var(--transition);
        }
        .btn-primary-custom:hover {
            background-color: #c70510;
            border-color: #c70510;
            transform: translateY(-3px);
            box-shadow: 0 10px 20px rgba(0,0,0,0.2);
        }
        .feature-icon {
            font-size: 2.5rem;
            color: var(--primary-color);
            margin-bottom: 1.5rem;
        }
        .card-hover {
            transition: var(--transition);
            height: 100%;
            border: none;
            box-shadow: 0 5px 15px rgba(0,0,0,0.08);
            border-radius: 10px;
            overflow: hidden;
        }
        .card-hover:hover {
            transform: translateY(-10px);
            box-shadow: 0 15px 30px rgba(0,0,0,0.15);
        }
        .product-img {
            height: 220px;
            object-fit: cover;
            transition: var(--transition);
        }
        .card-hover:hover .product-img {
            transform: scale(1.05);
        }
        .stats-section {
            background-color: var(--light-bg);
            padding: 5rem 0;
        }
        .stat-number {
            font-size: 3rem;
            font-weight: 800;
            color: var(--primary-color);
            display: block;
            line-height: 1;
        }
        .stat-label {
            font-size: 1.1rem;
            color: var(--secondary-color);
            font-weight: 600;
        }
        .flink {
            display: inline-block;
            background: var(--light-bg);
            padding: 10px 20px;
            margin: 8px;
            border-radius: 5px;
            color: var(--secondary-color);
            text-decoration: none;
            font-weight: 500;
            transition: var(--transition);
            border: 1px solid #dee2e6;
        }
        .flink:hover {
            background: var(--primary-color);
            color: white;
            transform: translateY(-3px);
        }
        .friendlink {
            background-color: #f8f9fa;
            padding: 4rem 0;
            border-top: 1px solid #eee;
            border-bottom: 1px solid #eee;
        }
        footer {
            background-color: var(--dark-bg);
            color: #adb5bd;
            padding-top: 3rem;
        }
        .footer-link {
            color: #adb5bd;
            text-decoration: none;
            transition: var(--transition);
        }
        .footer-link:hover {
            color: white;
            padding-left: 5px;
        }
        .social-icon {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            width: 40px;
            height: 40px;
            background: rgba(255,255,255,0.1);
            border-radius: 50%;
            margin-right: 10px;
            color: white;
            transition: var(--transition);
        }
        .social-icon:hover {
            background: var(--accent-color);
            transform: translateY(-5px);
        }
        .contact-info i {
            color: var(--primary-color);
            width: 20px;
            margin-right: 10px;
        }
        .back-to-top {
            position: fixed;
            bottom: 30px;
            right: 30px;
            width: 50px;
            height: 50px;
            background-color: var(--primary-color);
            color: white;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.2rem;
            z-index: 1000;
            opacity: 0;
            visibility: hidden;
            transition: var(--transition);
            text-decoration: none;
        }
        .back-to-top.active {
            opacity: 1;
            visibility: visible;
        }
        .back-to-top:hover {
            background-color: var(--accent-color);
            color: white;
        }
        @media (max-width: 768px) {
            .hero-title {
                font-size: 2.5rem;
            }
            .hero-section {
                padding: 6rem 0 4rem;
            }
            .section-header {
                margin-bottom: 2rem;
            }
        }