:root {
            --primary-color: #0a5cb8;
            --secondary-color: #f8f9fa;
            --accent-color: #ff6b35;
            --text-dark: #333;
            --text-light: #777;
            --shadow: 0 5px 15px rgba(0,0,0,0.08);
            --transition: all 0.3s ease;
        }
        body {
            font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
            color: var(--text-dark);
            overflow-x: hidden;
            line-height: 1.7;
        }
        .navbar-brand {
            font-weight: 700;
            font-size: 1.8rem;
            color: var(--primary-color) !important;
        }
        .navbar-brand span {
            color: var(--accent-color);
        }
        .nav-link {
            font-weight: 500;
            margin: 0 8px;
            transition: var(--transition);
        }
        .nav-link:hover {
            color: var(--primary-color) !important;
            transform: translateY(-2px);
        }
        .hero-section {
            background: linear-gradient(rgba(10, 92, 184, 0.85), rgba(6, 68, 138, 0.9)), url('https://images.unsplash.com/photo-1607082348824-0a96f2a4b9da?ixlib=rb-4.0.3&auto=format&fit=crop&w=2070&q=80') center/cover no-repeat;
            color: white;
            padding: 120px 0 100px;
        }
        .hero-section h1 {
            font-size: 3.2rem;
            font-weight: 800;
            margin-bottom: 25px;
            text-shadow: 2px 2px 8px rgba(0,0,0,0.3);
        }
        .section-title {
            position: relative;
            padding-bottom: 20px;
            margin-bottom: 50px;
            text-align: center;
            font-weight: 700;
            color: var(--primary-color);
        }
        .section-title:after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 50%;
            transform: translateX(-50%);
            width: 80px;
            height: 4px;
            background: var(--accent-color);
            border-radius: 2px;
        }
        .card-hover {
            transition: var(--transition);
            border: none;
            box-shadow: var(--shadow);
            height: 100%;
        }
        .card-hover:hover {
            transform: translateY(-12px);
            box-shadow: 0 15px 30px rgba(0,0,0,0.15);
        }
        .icon-box {
            width: 70px;
            height: 70px;
            background: rgba(10, 92, 184, 0.1);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-bottom: 20px;
            color: var(--primary-color);
            font-size: 1.8rem;
        }
        .btn-primary-custom {
            background: var(--primary-color);
            border: none;
            padding: 12px 32px;
            border-radius: 30px;
            font-weight: 600;
            transition: var(--transition);
        }
        .btn-primary-custom:hover {
            background: #084a9c;
            transform: translateY(-3px);
            box-shadow: 0 10px 20px rgba(10, 92, 184, 0.2);
        }
        .feature-item {
            padding: 30px;
            border-radius: 12px;
            background: white;
            box-shadow: var(--shadow);
            transition: var(--transition);
            height: 100%;
        }
        .feature-item:hover {
            background: var(--primary-color);
            color: white;
        }
        .feature-item:hover h4,
        .feature-item:hover .icon-box {
            color: white;
        }
        .feature-item:hover .icon-box {
            background: rgba(255,255,255,0.2);
        }
        .product-img {
            height: 220px;
            object-fit: cover;
            border-radius: 10px 10px 0 0;
        }
        .contact-info-box {
            background: white;
            padding: 30px;
            border-radius: 12px;
            box-shadow: var(--shadow);
            text-align: center;
            height: 100%;
            transition: var(--transition);
        }
        .contact-info-box:hover {
            transform: translateY(-10px);
        }
        .contact-info-box i {
            font-size: 2.5rem;
            color: var(--primary-color);
            margin-bottom: 20px;
        }
        footer {
            background: #1a1a2e;
            color: #aaa;
            padding-top: 70px;
        }
        footer a {
            color: #ccc;
            text-decoration: none;
            transition: var(--transition);
        }
        footer a:hover {
            color: white;
            padding-left: 5px;
        }
        .footer-bottom {
            border-top: 1px solid #333;
            padding: 20px 0;
            margin-top: 40px;
        }
        .flink {
            display: inline-block;
            background: rgba(255,255,255,0.05);
            padding: 10px 20px;
            margin: 5px 10px;
            border-radius: 30px;
            transition: var(--transition);
            border: 1px solid transparent;
        }
        .flink:hover {
            background: rgba(255,255,255,0.1);
            border-color: var(--primary-color);
            transform: translateY(-3px);
        }
        .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: 1.2rem;
            z-index: 1000;
            opacity: 0;
            visibility: hidden;
            transition: var(--transition);
        }
        .back-to-top.active {
            opacity: 1;
            visibility: visible;
        }
        .back-to-top:hover {
            background: var(--accent-color);
            transform: translateY(-5px);
        }
        @media (max-width: 768px) {
            .hero-section h1 {
                font-size: 2.5rem;
            }
            .hero-section {
                padding: 80px 0 60px;
            }
            .section-title {
                font-size: 1.8rem;
            }
        }