:root {
            --primary-color: #2a6ebb;
            --secondary-color: #34a8dd;
            --accent-color: #ff6b35;
            --dark-color: #1a365d;
            --light-color: #f8f9fa;
            --text-color: #333;
            --gray-light: #e9ecef;
        }
        body {
            font-family: 'Helvetica Neue', 'Microsoft YaHei', sans-serif;
            color: var(--text-color);
            line-height: 1.6;
        }
        h1, h2, h3, h4, h5, h6 {
            font-weight: 600;
            color: var(--dark-color);
        }
        .navbar {
            background-color: rgba(255, 255, 255, 0.95);
            box-shadow: 0 2px 15px rgba(0, 0, 0, 0.08);
            padding: 0.8rem 0;
            transition: all 0.3s ease;
        }
        .navbar-brand {
            font-weight: 700;
            font-size: 1.5rem;
            color: var(--primary-color) !important;
        }
        .navbar-brand span {
            color: var(--accent-color);
        }
        .nav-link {
            font-weight: 500;
            margin: 0 0.5rem;
            color: var(--dark-color) !important;
            transition: color 0.3s ease;
        }
        .nav-link:hover, .nav-link.active {
            color: var(--primary-color) !important;
        }
        .hero-section {
            background: linear-gradient(135deg, rgba(42, 110, 187, 0.9) 0%, rgba(52, 168, 221, 0.9) 100%), url('https://images.unsplash.com/photo-1451187580459-43490279c0fa?ixlib=rb-4.0.3&ixid=M3wxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8fA%3D%3D&auto=format&fit=crop&w=1772&q=80');
            background-size: cover;
            background-position: center;
            color: white;
            padding: 8rem 0 6rem;
        }
        .hero-title {
            font-size: 3.2rem;
            font-weight: 700;
            margin-bottom: 1.5rem;
        }
        .hero-subtitle {
            font-size: 1.3rem;
            margin-bottom: 2.5rem;
            opacity: 0.9;
        }
        .btn-primary {
            background-color: var(--primary-color);
            border-color: var(--primary-color);
            padding: 0.75rem 2rem;
            font-weight: 500;
            transition: all 0.3s ease;
        }
        .btn-primary:hover {
            background-color: var(--dark-color);
            border-color: var(--dark-color);
            transform: translateY(-3px);
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
        }
        .btn-outline-light:hover {
            color: var(--primary-color);
        }
        .section-title {
            position: relative;
            margin-bottom: 3.5rem;
            text-align: center;
        }
        .section-title:after {
            content: '';
            position: absolute;
            width: 80px;
            height: 4px;
            background: var(--primary-color);
            bottom: -15px;
            left: 50%;
            transform: translateX(-50%);
            border-radius: 2px;
        }
        .feature-card {
            background: white;
            border-radius: 12px;
            padding: 2.5rem 2rem;
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.05);
            height: 100%;
            transition: transform 0.3s ease, box-shadow 0.3s ease;
            border: 1px solid var(--gray-light);
        }
        .feature-card:hover {
            transform: translateY(-10px);
            box-shadow: 0 15px 40px rgba(0, 0, 0, 0.1);
        }
        .feature-icon {
            width: 80px;
            height: 80px;
            background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0 auto 1.5rem;
            color: white;
            font-size: 2rem;
        }
        .about-section {
            background-color: var(--light-color);
            padding: 6rem 0;
        }
        .service-card {
            background: white;
            border-radius: 12px;
            overflow: hidden;
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.05);
            transition: transform 0.3s ease;
            height: 100%;
        }
        .service-card:hover {
            transform: translateY(-10px);
        }
        .service-img {
            height: 200px;
            object-fit: cover;
            width: 100%;
        }
        .service-body {
            padding: 2rem;
        }
        .portfolio-section {
            padding: 6rem 0;
            background-color: white;
        }
        .portfolio-item {
            border-radius: 12px;
            overflow: hidden;
            margin-bottom: 2rem;
            box-shadow: 0 5px 20px rgba(0, 0, 0, 0.08);
            transition: transform 0.3s ease;
        }
        .portfolio-item:hover {
            transform: translateY(-8px);
        }
        .portfolio-img {
            width: 100%;
            height: 240px;
            object-fit: cover;
        }
        .portfolio-overlay {
            background: linear-gradient(to top, rgba(0,0,0,0.8), transparent);
            position: absolute;
            bottom: 0;
            left: 0;
            right: 0;
            padding: 1.5rem;
            color: white;
            transform: translateY(100%);
            transition: transform 0.3s ease;
        }
        .portfolio-item:hover .portfolio-overlay {
            transform: translateY(0);
        }
        .contact-section {
            background: linear-gradient(135deg, var(--dark-color) 0%, var(--primary-color) 100%);
            color: white;
            padding: 6rem 0;
        }
        .contact-info {
            background: rgba(255, 255, 255, 0.1);
            border-radius: 12px;
            padding: 2.5rem;
            height: 100%;
            backdrop-filter: blur(10px);
        }
        .contact-icon {
            width: 60px;
            height: 60px;
            background: rgba(255, 255, 255, 0.2);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-bottom: 1.5rem;
            font-size: 1.5rem;
        }
        .footer {
            background-color: #111;
            color: #aaa;
            padding: 4rem 0 2rem;
        }
        .footer a {
            color: #ccc;
            text-decoration: none;
            transition: color 0.3s ease;
        }
        .footer a:hover {
            color: white;
        }
        .footer-title {
            color: white;
            font-size: 1.2rem;
            margin-bottom: 1.5rem;
            position: relative;
            padding-bottom: 0.7rem;
        }
        .footer-title:after {
            content: '';
            position: absolute;
            width: 40px;
            height: 3px;
            background: var(--primary-color);
            bottom: 0;
            left: 0;
        }
        .flink {
            display: inline-block;
            background: rgba(255, 255, 255, 0.05);
            border-radius: 6px;
            padding: 0.5rem 1.2rem;
            margin: 0.3rem 0.5rem 0.3rem 0;
            transition: all 0.3s ease;
            color: #ccc;
            border: 1px solid rgba(255, 255, 255, 0.1);
        }
        .flink:hover {
            background: var(--primary-color);
            color: white;
            transform: translateY(-2px);
            border-color: var(--primary-color);
        }
        .copyright {
            border-top: 1px solid #333;
            padding-top: 1.5rem;
            margin-top: 3rem;
            text-align: center;
            font-size: 0.9rem;
        }
        .stats-card {
            background: white;
            border-radius: 12px;
            padding: 2rem;
            text-align: center;
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.05);
            border-left: 4px solid var(--primary-color);
        }
        .stats-number {
            font-size: 2.5rem;
            font-weight: 700;
            color: var(--primary-color);
            margin-bottom: 0.5rem;
        }
        .stats-label {
            color: #666;
            font-weight: 500;
        }
        .timeline {
            position: relative;
            padding-left: 30px;
        }
        .timeline:before {
            content: '';
            position: absolute;
            left: 0;
            top: 0;
            bottom: 0;
            width: 3px;
            background: var(--primary-color);
        }
        .timeline-item {
            position: relative;
            margin-bottom: 2.5rem;
        }
        .timeline-item:before {
            content: '';
            position: absolute;
            left: -36px;
            top: 5px;
            width: 15px;
            height: 15px;
            border-radius: 50%;
            background: var(--primary-color);
            border: 3px solid white;
            box-shadow: 0 0 0 3px var(--primary-color);
        }
        .timeline-date {
            font-weight: 600;
            color: var(--primary-color);
            margin-bottom: 0.5rem;
        }
        .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: all 0.3s ease;
            text-decoration: none;
        }
        .back-to-top.active {
            opacity: 1;
            visibility: visible;
        }
        .back-to-top:hover {
            background: var(--dark-color);
            color: white;
        }
        @media (max-width: 992px) {
            .hero-title {
                font-size: 2.5rem;
            }
            .hero-section {
                padding: 6rem 0 4rem;
            }
        }
        @media (max-width: 768px) {
            .hero-title {
                font-size: 2rem;
            }
            .hero-subtitle {
                font-size: 1.1rem;
            }
            .section-title {
                font-size: 1.8rem;
            }
        }