:root {
            --primary-color: #1a56db;
            --secondary-color: #046c4e;
            --accent-color: #f3b919;
            --light-color: #f8fafc;
            --dark-color: #1e293b;
            --gray-color: #64748b;
        }
        body {
            font-family: 'Microsoft YaHei', 'Segoe UI', system-ui, sans-serif;
            line-height: 1.8;
            color: var(--dark-color);
            overflow-x: hidden;
        }
        .section-header {
            position: relative;
            margin-bottom: 3rem;
            text-align: center;
        }
        .section-header h2 {
            font-weight: 700;
            color: var(--dark-color);
            display: inline-block;
            padding-bottom: 15px;
        }
        .section-header h2:after {
            content: '';
            position: absolute;
            width: 70px;
            height: 4px;
            background: var(--primary-color);
            bottom: 0;
            left: 50%;
            transform: translateX(-50%);
            border-radius: 2px;
        }
        .hero-section {
            background: linear-gradient(135deg, rgba(26, 86, 219, 0.9) 0%, rgba(4, 108, 78, 0.85) 100%), url('https://images.unsplash.com/photo-1499750310107-5fef28a66643?ixlib=rb-4.0.3&ixid=M3wxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8fA%3D%3D&auto=format&fit=crop&w=2070&q=80') no-repeat center center;
            background-size: cover;
            color: white;
            padding: 120px 0 80px;
            position: relative;
        }
        .hero-content h1 {
            font-size: 3.5rem;
            font-weight: 800;
            margin-bottom: 1.5rem;
            text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
        }
        .hero-content p {
            font-size: 1.25rem;
            margin-bottom: 2rem;
            opacity: 0.95;
        }
        .btn-custom-primary {
            background-color: var(--accent-color);
            border-color: var(--accent-color);
            color: var(--dark-color);
            font-weight: 600;
            padding: 0.75rem 2rem;
            border-radius: 50px;
            transition: all 0.3s ease;
        }
        .btn-custom-primary:hover {
            background-color: #e0a800;
            border-color: #e0a800;
            transform: translateY(-3px);
            box-shadow: 0 10px 20px rgba(0,0,0,0.2);
        }
        .service-card {
            border: none;
            border-radius: 12px;
            overflow: hidden;
            transition: transform 0.4s ease, box-shadow 0.4s ease;
            height: 100%;
            box-shadow: 0 5px 15px rgba(0,0,0,0.08);
            background: white;
        }
        .service-card:hover {
            transform: translateY(-10px);
            box-shadow: 0 15px 30px rgba(0,0,0,0.15);
        }
        .service-icon {
            width: 80px;
            height: 80px;
            background: linear-gradient(135deg, var(--primary-color), #3b82f6);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: -40px auto 20px;
            color: white;
            font-size: 2rem;
            box-shadow: 0 5px 15px rgba(26, 86, 219, 0.3);
        }
        .feature-box {
            padding: 2rem;
            border-radius: 12px;
            background: var(--light-color);
            transition: all 0.3s ease;
            height: 100%;
        }
        .feature-box:hover {
            background: white;
            box-shadow: 0 10px 25px rgba(0,0,0,0.1);
        }
        .feature-box i {
            color: var(--primary-color);
            font-size: 2.5rem;
            margin-bottom: 1.5rem;
        }
        .case-study-card {
            border-radius: 12px;
            overflow: hidden;
            box-shadow: 0 5px 15px rgba(0,0,0,0.08);
            transition: transform 0.3s ease;
            height: 100%;
        }
        .case-study-card:hover {
            transform: scale(1.03);
        }
        .case-study-card img {
            height: 220px;
            object-fit: cover;
            width: 100%;
        }
        .news-card {
            border-left: 4px solid var(--primary-color);
            padding-left: 1.5rem;
            transition: all 0.3s ease;
            margin-bottom: 2rem;
        }
        .news-card:hover {
            border-left-color: var(--accent-color);
            padding-left: 2rem;
            background-color: #f8fafc;
        }
        .news-date {
            color: var(--gray-color);
            font-size: 0.9rem;
            display: block;
            margin-bottom: 0.5rem;
        }
        .flink {
            display: inline-block;
            padding: 0.5rem 1.5rem;
            margin: 0.5rem;
            background: #f1f5f9;
            border-radius: 50px;
            color: var(--dark-color);
            text-decoration: none;
            transition: all 0.3s ease;
            font-weight: 500;
        }
        .flink:hover {
            background: var(--primary-color);
            color: white;
            transform: translateY(-3px);
        }
        .footer {
            background: var(--dark-color);
            color: #cbd5e1;
            padding-top: 3rem;
        }
        .footer a {
            color: #cbd5e1;
            text-decoration: none;
            transition: color 0.3s ease;
        }
        .footer a:hover {
            color: white;
        }
        .footer-bottom {
            border-top: 1px solid #334155;
            padding: 1.5rem 0;
            margin-top: 3rem;
            font-size: 0.9rem;
        }
        .contact-info li {
            margin-bottom: 1rem;
            display: flex;
            align-items: flex-start;
        }
        .contact-info i {
            margin-right: 10px;
            color: var(--accent-color);
            margin-top: 5px;
        }
        .navbar {
            background: rgba(255, 255, 255, 0.98);
            box-shadow: 0 2px 10px rgba(0,0,0,0.1);
            padding: 1rem 0;
            transition: all 0.3s ease;
        }
        .navbar.scrolled {
            padding: 0.7rem 0;
        }
        .nav-link {
            font-weight: 500;
            margin: 0 0.5rem;
            color: var(--dark-color) !important;
            position: relative;
        }
        .nav-link:hover {
            color: var(--primary-color) !important;
        }
        .nav-link:after {
            content: '';
            position: absolute;
            width: 0;
            height: 2px;
            background: var(--primary-color);
            left: 0;
            bottom: 0;
            transition: width 0.3s ease;
        }
        .nav-link:hover:after {
            width: 100%;
        }
        .navbar-brand {
            font-weight: 700;
            font-size: 1.8rem;
            color: var(--primary-color) !important;
        }
        .mobile-menu-btn {
            border: none;
            background: transparent;
            font-size: 1.5rem;
            color: var(--dark-color);
        }
        @media (max-width: 992px) {
            .hero-content h1 {
                font-size: 2.5rem;
            }
            .hero-content p {
                font-size: 1.1rem;
            }
        }
        @media (max-width: 768px) {
            .hero-section {
                padding: 100px 0 60px;
            }
            .hero-content h1 {
                font-size: 2rem;
            }
            .section-header h2 {
                font-size: 1.8rem;
            }
            .flink {
                padding: 0.4rem 1rem;
                font-size: 0.9rem;
                margin: 0.3rem;
            }
        }
        .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;
            text-decoration: none;
            opacity: 0;
            visibility: hidden;
            transition: all 0.3s ease;
            z-index: 1000;
        }
        .back-to-top.show {
            opacity: 1;
            visibility: visible;
        }
        .back-to-top:hover {
            background: var(--secondary-color);
            color: white;
        }