:root {
            --primary-color: #1a365d;
            --secondary-color: #e63946;
            --accent-color: #457b9d;
            --light-color: #f8f9fa;
            --dark-color: #212529;
            --gray-color: #6c757d;
        }
        body {
            font-family: 'Noto Sans SC', 'Microsoft YaHei', sans-serif;
            color: var(--dark-color);
            line-height: 1.8;
            overflow-x: hidden;
        }
        .navbar-brand {
            font-weight: 700;
            font-size: 1.8rem;
            color: var(--primary-color) !important;
        }
        .navbar-nav .nav-link {
            font-weight: 500;
            padding: 0.5rem 1.2rem !important;
            transition: all 0.3s ease;
        }
        .navbar-nav .nav-link:hover {
            color: var(--secondary-color) !important;
            transform: translateY(-2px);
        }
        .hero-section {
            background: linear-gradient(rgba(26, 54, 93, 0.85), rgba(69, 123, 157, 0.8)), url('https://images.unsplash.com/photo-1497366754035-f200968a6e72?ixlib=rb-4.0.3&auto=format&fit=crop&w=2069&q=80') center/cover no-repeat;
            color: white;
            padding: 8rem 0;
            min-height: 90vh;
            display: flex;
            align-items: center;
        }
        .hero-title {
            font-size: 3.5rem;
            font-weight: 800;
            margin-bottom: 1.5rem;
            text-shadow: 2px 2px 5px rgba(0,0,0,0.3);
        }
        .section-title {
            font-size: 2.5rem;
            font-weight: 700;
            color: var(--primary-color);
            position: relative;
            margin-bottom: 3rem;
            padding-bottom: 1rem;
        }
        .section-title::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 80px;
            height: 4px;
            background: var(--secondary-color);
        }
        .card-hover {
            transition: transform 0.3s ease, box-shadow 0.3s ease;
            height: 100%;
        }
        .card-hover:hover {
            transform: translateY(-10px);
            box-shadow: 0 15px 30px rgba(0,0,0,0.1) !important;
        }
        .service-icon {
            font-size: 3rem;
            color: var(--accent-color);
            margin-bottom: 1.5rem;
        }
        .project-img {
            height: 250px;
            object-fit: cover;
            transition: transform 0.5s ease;
        }
        .project-card:hover .project-img {
            transform: scale(1.05);
        }
        .flink {
            display: inline-block;
            padding: 0.5rem 1.2rem;
            margin: 0.3rem;
            background: var(--light-color);
            border-radius: 50px;
            color: var(--dark-color);
            text-decoration: none;
            font-weight: 500;
            transition: all 0.3s ease;
            border: 1px solid #dee2e6;
        }
        .flink:hover {
            background: var(--primary-color);
            color: white;
            transform: translateY(-3px);
        }
        .contact-info li {
            margin-bottom: 1rem;
            padding-left: 1.5rem;
            position: relative;
        }
        .contact-info li i {
            position: absolute;
            left: 0;
            top: 0.5rem;
            color: var(--secondary-color);
        }
        .footer {
            background: var(--primary-color);
            color: white;
            padding: 4rem 0 2rem;
        }
        .footer a {
            color: #adb5bd;
            text-decoration: none;
            transition: color 0.3s ease;
        }
        .footer a:hover {
            color: white;
        }
        .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: 1.5rem;
            cursor: pointer;
            z-index: 999;
            opacity: 0;
            transition: opacity 0.3s ease, transform 0.3s ease;
        }
        .back-to-top.show {
            opacity: 1;
        }
        .back-to-top:hover {
            transform: translateY(-5px);
        }
        @media (max-width: 768px) {
            .hero-title {
                font-size: 2.5rem;
            }
            .section-title {
                font-size: 2rem;
            }
        }