:root {
            --primary-color: #1a365d;
            --secondary-color: #e63946;
            --accent-color: #457b9d;
            --light-color: #f8f9fa;
            --dark-color: #212529;
            --transition: all 0.3s ease;
        }
        body {
            font-family: 'Helvetica Neue', Arial, 'Microsoft YaHei', sans-serif;
            color: #333;
            line-height: 1.7;
        }
        .navbar-brand {
            font-weight: 700;
            font-size: 1.8rem;
            color: var(--primary-color);
        }
        .navbar-brand span {
            color: var(--secondary-color);
        }
        .hero-section {
            background: linear-gradient(rgba(0, 0, 0, 0.7), rgba(0, 0, 0, 0.7)), url('https://images.unsplash.com/photo-1611974789855-9c2a0a7236a3?ixlib=rb-4.0.3&auto=format&fit=crop&w=1920&q=80') no-repeat center center;
            background-size: cover;
            color: white;
            padding: 180px 0 120px;
        }
        .section-title {
            position: relative;
            padding-bottom: 15px;
            margin-bottom: 50px;
            font-weight: 700;
            color: var(--primary-color);
        }
        .section-title:after {
            content: '';
            position: absolute;
            left: 0;
            bottom: 0;
            width: 60px;
            height: 4px;
            background: var(--secondary-color);
        }
        .text-center .section-title:after {
            left: 50%;
            transform: translateX(-50%);
        }
        .card {
            border: none;
            box-shadow: 0 5px 15px rgba(0,0,0,0.08);
            transition: var(--transition);
            height: 100%;
        }
        .card:hover {
            transform: translateY(-10px);
            box-shadow: 0 15px 30px rgba(0,0,0,0.15);
        }
        .card-icon {
            width: 70px;
            height: 70px;
            background: var(--primary-color);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0 auto 25px;
            color: white;
            font-size: 1.8rem;
        }
        .service-box, .team-member {
            transition: var(--transition);
        }
        .service-box:hover, .team-member:hover {
            transform: translateY(-10px);
        }
        .team-member img {
            width: 200px;
            height: 200px;
            object-fit: cover;
            border-radius: 50%;
            border: 5px solid #f1f1f1;
            margin-bottom: 20px;
        }
        .testimonial-slide {
            background: var(--light-color);
            border-radius: 10px;
            padding: 30px;
        }
        .client-logo {
            height: 80px;
            display: flex;
            align-items: center;
            justify-content: center;
            filter: grayscale(100%);
            opacity: 0.6;
            transition: var(--transition);
        }
        .client-logo:hover {
            filter: grayscale(0);
            opacity: 1;
        }
        footer {
            background: var(--primary-color);
            color: white;
        }
        footer a {
            color: #ccc;
            text-decoration: none;
            transition: var(--transition);
        }
        footer a:hover {
            color: white;
        }
        .flink {
            background: rgba(255,255,255,0.1);
            padding: 10px 20px;
            border-radius: 5px;
            display: inline-block;
            margin: 5px;
            transition: var(--transition);
        }
        .flink:hover {
            background: rgba(255,255,255,0.2);
            transform: translateY(-3px);
        }
        .contact-info li {
            margin-bottom: 15px;
            padding-left: 30px;
            position: relative;
        }
        .contact-info li i {
            position: absolute;
            left: 0;
            top: 5px;
            color: var(--secondary-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;
            z-index: 1000;
            opacity: 0;
            visibility: hidden;
            transition: var(--transition);
        }
        .back-to-top.active {
            opacity: 1;
            visibility: visible;
        }
        @media (max-width: 768px) {
            .hero-section {
                padding: 120px 0 80px;
            }
            .display-4 {
                font-size: 2.2rem;
            }
        }