:root {
            --primary-color: #1a365d;
            --secondary-color: #2d7dd2;
            --accent-color: #ff6b35;
            --light-color: #f8f9fa;
            --dark-color: #212529;
            --transition: all 0.3s ease;
        }
        body {
            font-family: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
            color: var(--dark-color);
            overflow-x: hidden;
        }
        h1, h2, h3, h4, h5, h6 {
            font-weight: 700;
            color: var(--primary-color);
        }
        .navbar-brand {
            font-size: 1.8rem;
            font-weight: 800;
            color: var(--primary-color) !important;
        }
        .navbar-brand span {
            color: var(--accent-color);
        }
        .nav-link {
            font-weight: 500;
            margin: 0 0.5rem;
            transition: var(--transition);
            position: relative;
        }
        .nav-link:hover, .nav-link.active {
            color: var(--accent-color) !important;
        }
        .nav-link::after {
            content: '';
            position: absolute;
            width: 0;
            height: 2px;
            bottom: 0;
            left: 0;
            background-color: var(--accent-color);
            transition: var(--transition);
        }
        .nav-link:hover::after, .nav-link.active::after {
            width: 100%;
        }
        .hero-section {
            background: linear-gradient(135deg, rgba(26, 54, 93, 0.9) 0%, rgba(45, 125, 210, 0.8) 100%), url('https://images.unsplash.com/photo-1497366216548-37526070297c?ixlib=rb-4.0.3&auto=format&fit=crop&w=1920&q=80');
            background-size: cover;
            background-position: center;
            color: white;
            padding: 10rem 0;
            position: relative;
        }
        .section-title {
            position: relative;
            margin-bottom: 3rem;
            text-align: center;
        }
        .section-title::after {
            content: '';
            position: absolute;
            width: 80px;
            height: 4px;
            background: var(--accent-color);
            bottom: -15px;
            left: 50%;
            transform: translateX(-50%);
        }
        .service-card {
            border: none;
            border-radius: 12px;
            overflow: hidden;
            transition: var(--transition);
            height: 100%;
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.08);
        }
        .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(--secondary-color), var(--primary-color));
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0 auto 1.5rem;
            color: white;
            font-size: 2rem;
        }
        .portfolio-item {
            position: relative;
            overflow: hidden;
            border-radius: 12px;
            margin-bottom: 1.5rem;
        }
        .portfolio-item img {
            transition: var(--transition);
            width: 100%;
            height: 300px;
            object-fit: cover;
        }
        .portfolio-overlay {
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: rgba(26, 54, 93, 0.85);
            color: white;
            display: flex;
            flex-direction: column;
            justify-content: center;
            align-items: center;
            opacity: 0;
            transition: var(--transition);
            padding: 1.5rem;
        }
        .portfolio-item:hover .portfolio-overlay {
            opacity: 1;
        }
        .portfolio-item:hover img {
            transform: scale(1.05);
        }
        .testimonial-card {
            background: var(--light-color);
            border-radius: 12px;
            padding: 2rem;
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
            height: 100%;
        }
        .client-logo {
            max-width: 150px;
            filter: grayscale(100%);
            opacity: 0.7;
            transition: var(--transition);
        }
        .client-logo:hover {
            filter: grayscale(0);
            opacity: 1;
        }
        .flink {
            display: inline-block;
            padding: 0.5rem 1.5rem;
            margin: 0.5rem;
            background: var(--light-color);
            border-radius: 50px;
            color: var(--dark-color);
            text-decoration: none;
            transition: var(--transition);
            border: 1px solid #dee2e6;
            font-weight: 500;
        }
        .flink:hover {
            background: var(--secondary-color);
            color: white;
            border-color: var(--secondary-color);
            transform: translateY(-3px);
        }
        .contact-info-item {
            background: white;
            padding: 2rem;
            border-radius: 12px;
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
            text-align: center;
            transition: var(--transition);
            height: 100%;
        }
        .contact-info-item:hover {
            transform: translateY(-5px);
            box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
        }
        .contact-icon {
            width: 60px;
            height: 60px;
            background: linear-gradient(135deg, var(--accent-color), #ff8c5a);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0 auto 1.5rem;
            color: white;
            font-size: 1.5rem;
        }
        footer {
            background: var(--primary-color);
            color: rgba(255, 255, 255, 0.85);
        }
        footer a {
            color: rgba(255, 255, 255, 0.85);
            text-decoration: none;
            transition: var(--transition);
        }
        footer a:hover {
            color: white;
            text-decoration: underline;
        }
        .footer-links {
            list-style: none;
            padding: 0;
        }
        .footer-links li {
            margin-bottom: 0.5rem;
        }
        .back-to-top {
            position: fixed;
            bottom: 30px;
            right: 30px;
            width: 50px;
            height: 50px;
            background: var(--accent-color);
            color: white;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            text-decoration: none;
            opacity: 0;
            visibility: hidden;
            transition: var(--transition);
            z-index: 1000;
        }
        .back-to-top.show {
            opacity: 1;
            visibility: visible;
        }
        .back-to-top:hover {
            background: var(--primary-color);
            color: white;
        }
        .form-control:focus, .form-select:focus {
            border-color: var(--secondary-color);
            box-shadow: 0 0 0 0.25rem rgba(45, 125, 210, 0.25);
        }
        .btn-primary {
            background-color: var(--secondary-color);
            border-color: var(--secondary-color);
            padding: 0.75rem 2rem;
            font-weight: 600;
        }
        .btn-primary:hover {
            background-color: var(--primary-color);
            border-color: var(--primary-color);
        }
        @media (max-width: 768px) {
            .hero-section {
                padding: 6rem 0;
            }
            .display-4 {
                font-size: 2.5rem;
            }
            .section-title::after {
                width: 60px;
            }
        }