/* 导入字体 */
    @import url('https://fonts.googleapis.com/css2?family=Roboto:wght@400;700&family=Open+Sans:wght@400;600&display=swap');

    /* 全局样式 */
    * {
        margin: 0;
        padding: 0;
        box-sizing: border-box;
    }

    body {
        font-family: 'Open Sans', sans-serif;
        color: #ffffff;
        background: radial-gradient(circle, rgba(0,4,40,1) 0%, rgba(0,78,146,1) 50%, rgba(44,83,100,1) 100%);
        animation: aurora-move 15s linear infinite;
        line-height: 1.6;
    }

    a {
        color: #ffffff;
        text-decoration: none;
        rel: nofollow;
    }

    a:hover {
        text-decoration: underline;
    }

    header {
        width: 100%;
        padding: 20px 40px;
        position: fixed;
        top: 0;
        left: 0;
        background: rgba(0, 4, 40, 0.8);
        display: flex;
        justify-content: space-between;
        align-items: center;
        z-index: 1000;
        transition: background 0.5s ease;
    }

    header.scrolled {
        background: rgba(0, 78, 146, 0.9);
    }

    header h1 {
        font-family: 'Roboto', sans-serif;
        font-size: 24px;
        font-weight: 700;
    }

    nav ul {
        list-style: none;
        display: flex;
        gap: 20px;
    }

    nav ul li a {
        font-family: 'Roboto', sans-serif;
        font-weight: 600;
        transition: color 0.3s ease;
    }

    nav ul li a:hover {
        color: #00ffdd;
    }

    main {
        padding: 100px 40px 40px 40px;
        max-width: 1200px;
        margin: 0 auto;
    }

    section {
        margin-bottom: 60px;
        padding: 40px;
        border-radius: 15px;
        background: rgba(255, 255, 255, 0.1);
        box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
        backdrop-filter: blur(10px);
        -webkit-backdrop-filter: blur(10px);
        border: 1px solid rgba(255, 255, 255, 0.3);
    }

    section.about {
        background: linear-gradient(135deg, #000428, #004e92);
    }

    section.services {
        background: linear-gradient(135deg, #2c5364, #203a43);
    }

    section.case-studies {
        background: linear-gradient(135deg, #2c5364, #203a43);
    }

    section.contact {
        background: linear-gradient(135deg, #000428, #004e92);
    }

    section h2 {
        font-family: 'Roboto', sans-serif;
        font-size: 32px;
        margin-bottom: 20px;
        text-align: center;
        position: relative;
    }

    section h2::after {
        content: '';
        width: 50px;
        height: 4px;
        background: #00ffdd;
        display: block;
        margin: 10px auto 0;
        border-radius: 2px;
    }

    .button {
        display: inline-block;
        background: #004e92;
        color: #ffffff;
        padding: 12px 30px;
        border: none;
        border-radius: 25px;
        font-family: 'Roboto', sans-serif;
        font-weight: 700;
        cursor: pointer;
        transition: background 0.3s ease, transform 0.3s ease;
        margin-top: 20px;
    }

    .button:hover {
        background: #0077b6;
        transform: scale(1.05);
    }

    .cards {
        display: flex;
        flex-wrap: wrap;
        gap: 20px;
        justify-content: center;
    }

    .card {
        background: linear-gradient(135deg, #000428, #004e92);
        color: #ffffff;
        padding: 20px;
        border-radius: 15px;
        width: 250px;
        box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
        transition: transform 0.3s ease, box-shadow 0.3s ease;
    }

    .card:hover {
        transform: translateY(-10px);
        box-shadow: 0 12px 24px rgba(0, 0, 0, 0.3);
    }

    .card img {
        width: 50px;
        height: 50px;
        margin-bottom: 15px;
    }

    .card h3 {
        font-family: 'Roboto', sans-serif;
        font-size: 20px;
        margin-bottom: 10px;
    }

    .card p {
        font-size: 16px;
        line-height: 1.5;
    }

    .case-studies .chart {
        width: 100%;
        max-width: 600px;
        margin: 0 auto;
        position: relative;
    }

    .case-studies .chart img {
        width: 100%;
        height: auto;
        border-radius: 10px;
    }

    .sample-article {
        background: rgba(255, 255, 255, 0.05);
        padding: 30px;
        border-radius: 10px;
        overflow: hidden;
    }

    .sample-article h2 {
        font-size: 28px;
        margin-bottom: 15px;
    }

    .sample-article h3 {
        font-size: 24px;
        margin-top: 20px;
        margin-bottom: 10px;
    }

    .sample-article pre {
        background: #1e1e1e;
        padding: 15px;
        border-radius: 5px;
        overflow-x: auto;
        margin-bottom: 15px;
    }

    .sample-article code {
        color: #00ffdd;
        font-family: 'Courier New', Courier, monospace;
    }

    .floating-particles {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        pointer-events: none;
        background: transparent;
        z-index: 500;
    }

    .floating-particles::before, .floating-particles::after {
        content: '';
        position: absolute;
        width: 100%;
        height: 100%;
        background: radial-gradient(circle, rgba(255,255,255,0.1) 1px, transparent 1px);
        background-size: 50px 50px;
        animation: float 10s linear infinite;
    }

    .floating-particles::after {
        animation-direction: reverse;
    }

    @keyframes aurora-move {
        0% { background-position: 0% 50%; }
        50% { background-position: 100% 50%; }
        100% { background-position: 0% 50%; }
    }

    @keyframes float {
        0% { transform: translateY(0); }
        100% { transform: translateY(-100px); }
    }

    @media (max-width: 1440px) {
        main {
            padding: 80px 30px 30px 30px;
        }
    }

    @media (max-width: 1200px) {
        header {
            padding: 15px 30px;
        }

        nav ul {
            gap: 15px;
        }

        section {
            padding: 30px;
        }

        .card {
            width: 220px;
        }
    }

    @media (max-width: 1024px) {
        main {
            padding: 70px 20px 20px 20px;
        }

        .cards {
            flex-direction: column;
            align-items: center;
        }

        .case-studies .chart {
            max-width: 100%;
        }
    }

    @media (max-width: 768px) {
        header {
            flex-direction: column;
            align-items: flex-start;
        }

        nav ul {
            flex-direction: column;
            gap: 10px;
            margin-top: 10px;
        }

        section {
            padding: 20px;
        }

        .card {
            width: 100%;
        }
    }

    @media (max-width: 480px) {
        header h1 {
            font-size: 20px;
        }

        nav ul li a {
            font-size: 14px;
        }

        section h2 {
            font-size: 24px;
        }

        .button {
            padding: 10px 20px;
            font-size: 14px;
        }

        .sample-article h2 {
            font-size: 24px;
        }

        .sample-article h3 {
            font-size: 20px;
        }
    }

    @media (max-width: 320px) {
        main {
            padding: 60px 15px 15px 15px;
        }

        header h1 {
            font-size: 18px;
        }

        nav ul li a {
            font-size: 12px;
        }

        section h2 {
            font-size: 20px;
        }

        .button {
            padding: 8px 16px;
            font-size: 12px;
        }

        .sample-article h2 {
            font-size: 20px;
        }

        .sample-article h3 {
            font-size: 18px;
        }
    }