:root {
            --primary-color: #1a3a5f;
            --secondary-color: #4a90e2;
            --accent-color: #f5a623;
            --light-color: #f8f9fa;
            --dark-color: #333;
        }
        body {
            font-family: 'Microsoft YaHei', 'Segoe UI', sans-serif;
            color: #444;
            line-height: 1.7;
        }
        h1, h2, h3, h4, h5 {
            font-weight: 700;
            color: var(--primary-color);
        }
        .navbar {
            background-color: rgba(255, 255, 255, 0.95);
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
            padding: 0.8rem 0;
            transition: all 0.3s ease;
        }
        .navbar-brand {
            font-weight: 800;
            font-size: 1.8rem;
            color: var(--primary-color) !important;
        }
        .navbar-brand span {
            color: var(--secondary-color);
        }
        .nav-link {
            font-weight: 600;
            color: var(--primary-color) !important;
            margin: 0 0.5rem;
            padding: 0.5rem 1rem !important;
            border-radius: 4px;
            transition: all 0.3s ease;
        }
        .nav-link:hover, .nav-link.active {
            background-color: var(--secondary-color);
            color: white !important;
        }
        .hero-section {
            background: linear-gradient(rgba(26, 58, 95, 0.85), rgba(26, 58, 95, 0.9)), url('https://images.unsplash.com/photo-1518709268805-4e9042af2176?ixlib=rb-4.0.3&auto=format&fit=crop&w=1920&q=80') no-repeat center center/cover;
            color: white;
            padding: 8rem 0 6rem;
        }
        .hero-title {
            font-size: 3.5rem;
            font-weight: 800;
            margin-bottom: 1.5rem;
            text-shadow: 2px 2px 8px rgba(0, 0, 0, 0.3);
        }
        .hero-subtitle {
            font-size: 1.4rem;
            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 2.5rem;
            font-weight: 600;
            border-radius: 50px;
            transition: all 0.3s ease;
        }
        .btn-primary-custom:hover {
            background-color: #e69500;
            border-color: #e69500;
            transform: translateY(-3px);
            box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
        }
        .section-title {
            position: relative;
            padding-bottom: 1rem;
            margin-bottom: 3rem;
            text-align: center;
        }
        .section-title:after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 50%;
            transform: translateX(-50%);
            width: 80px;
            height: 4px;
            background: var(--secondary-color);
            border-radius: 2px;
        }
        .icon-box {
            background: white;
            padding: 2.5rem 2rem;
            border-radius: 12px;
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.05);
            height: 100%;
            transition: all 0.4s ease;
            border-top: 5px solid transparent;
        }
        .icon-box:hover {
            transform: translateY(-10px);
            border-top-color: var(--secondary-color);
            box-shadow: 0 15px 40px rgba(0, 0, 0, 0.1);
        }
        .icon-box i {
            font-size: 3rem;
            color: var(--secondary-color);
            margin-bottom: 1.5rem;
        }
        .service-img {
            border-radius: 12px;
            overflow: hidden;
            box-shadow: 0 15px 40px rgba(0, 0, 0, 0.1);
            transition: all 0.4s ease;
        }
        .service-img:hover {
            transform: scale(1.03);
        }
        .project-card {
            border-radius: 12px;
            overflow: hidden;
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
            transition: all 0.4s ease;
            height: 100%;
        }
        .project-card:hover {
            transform: translateY(-10px);
            box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
        }
        .project-card img {
            height: 250px;
            object-fit: cover;
            transition: all 0.6s ease;
        }
        .project-card:hover img {
            transform: scale(1.1);
        }
        .news-card {
            border: none;
            border-radius: 12px;
            overflow: hidden;
            box-shadow: 0 8px 25px rgba(0, 0, 0, 0.05);
            transition: all 0.3s ease;
            height: 100%;
        }
        .news-card:hover {
            box-shadow: 0 15px 35px rgba(0, 0, 0, 0.1);
        }
        .news-date {
            position: absolute;
            top: 15px;
            left: 15px;
            background: var(--secondary-color);
            color: white;
            padding: 8px 15px;
            border-radius: 50px;
            font-weight: 600;
            font-size: 0.9rem;
        }
        .client-logo {
            filter: grayscale(100%);
            opacity: 0.7;
            transition: all 0.3s ease;
            padding: 1.5rem;
        }
        .client-logo:hover {
            filter: grayscale(0);
            opacity: 1;
        }
        footer {
            background-color: var(--primary-color);
            color: #ddd;
            padding-top: 4rem;
        }
        footer h5 {
            color: white;
            margin-bottom: 1.8rem;
            position: relative;
            padding-bottom: 0.8rem;
        }
        footer h5:after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 50px;
            height: 3px;
            background: var(--accent-color);
        }
        footer a {
            color: #bbb;
            text-decoration: none;
            transition: all 0.3s ease;
        }
        footer a:hover {
            color: white;
            padding-left: 5px;
        }
        .footer-contact li {
            margin-bottom: 1rem;
        }
        .footer-contact i {
            color: var(--accent-color);
            width: 24px;
        }
        .social-links a {
            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;
            transition: all 0.3s ease;
        }
        .social-links a:hover {
            background: var(--accent-color);
            transform: translateY(-5px);
        }
        .copyright {
            background-color: rgba(0, 0, 0, 0.2);
            padding: 1.5rem 0;
            margin-top: 3rem;
            font-size: 0.95rem;
        }
        .flink {
            display: inline-block;
            background: rgba(255, 255, 255, 0.08);
            padding: 0.6rem 1.5rem;
            margin: 0.3rem;
            border-radius: 50px;
            color: #bbb;
            text-decoration: none;
            transition: all 0.3s ease;
            border: 1px solid rgba(255, 255, 255, 0.1);
        }
        .flink:hover {
            background: rgba(255, 255, 255, 0.15);
            color: white;
            border-color: var(--accent-color);
        }
        .back-to-top {
            position: fixed;
            bottom: 30px;
            right: 30px;
            width: 50px;
            height: 50px;
            background: var(--secondary-color);
            color: white;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.2rem;
            text-decoration: none;
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
            opacity: 0;
            visibility: hidden;
            transition: all 0.4s ease;
            z-index: 1000;
        }
        .back-to-top.active {
            opacity: 1;
            visibility: visible;
        }
        .back-to-top:hover {
            background: var(--primary-color);
            transform: translateY(-5px);
        }
        @media (max-width: 768px) {
            .hero-title {
                font-size: 2.5rem;
            }
            .hero-subtitle {
                font-size: 1.2rem;
            }
            .navbar-nav {
                text-align: center;
                padding-top: 1rem;
            }
            .nav-link {
                margin: 0.2rem 0;
            }
        }