/* 导航链接样式 */
nav a {
    color: #fff;
    text-decoration: none;
    font-size: 20px;
    font-weight: 500;
    transition: color 0.2s;
    position: relative;
    padding: 0 22px;
}

    /* 下划线效果 - 初始状态不显示 */
    nav a::after {
        content: '';
        display: block;
        width: 0;
        height: 2px;
        background: #fff;
        position: absolute;
        left: 0;
        bottom: -4px;
        border-radius: 2px;
        transition: width 0.3s ease; /* 平滑过渡效果 */
    }

    /* 激活状态的下划线 */
    nav a.active::after {
        width: 80%; /* 激活时显示下划线 */
    }

    /* 悬停效果 - 可选增强 */
    nav a:hover::after {
        width: 80%; /* 悬停时也显示下划线 */
    }
    

:root {
    --main-color: #3C8CFF;
    --nav-height: 100px;
    --border-radius: 16px;
    --shadow: 0 4px 24px rgba(60,140,255,0.08);
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: 'Roboto', '微软雅黑', Arial, sans-serif;
    background: #f7f9fb;
    color: #222;
}

header {
    width: 100%;
    height: var(--nav-height);
    background: var(--main-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 40px;
    position: fixed;
    top: 0;
    left: 0;
    z-index: 100;
    box-shadow: 0 2px 8px rgba(60,140,255,0.08);
}

.logo-area {
    display: flex;
    align-items: center;
}

.logo-img {
    width: 40px;
    height: 40px;
    border-radius: 12px;
    background: #fff;
    margin-right: 14px;
    object-fit: cover;
}

.company-name {
    color: #fff;
    font-size: 22px;
    font-weight: bold;
    letter-spacing: 2px;
}

nav {
    display: flex;
    gap: 36px;
}

    nav a {
        color: #fff;
        text-decoration: none;
        font-size: 20px;
        font-weight: 500;
        transition: color 0.2s;
        position: relative;
        padding: 0 22px;
    }

        nav a:hover::after,
        nav a.active::after {
            content: '';
            display: block;
            width: 100%;
            height: 2px;
            background: #fff;
            position: absolute;
            left: 0;
            bottom: -4px;
            border-radius: 2px;
        }

main {
    margin-top: var(--nav-height);
}

.section, .product-intro, .download-section, .steps-section, .about-section {
    max-width: 90vw;
    margin-left: 5vw;
    margin-right: 5vw;
    box-sizing: border-box;
}

.section {
    padding: 60px 0 40px 0;
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
}
/* 产品介绍 */
.product-intro {
    display: flex;
    flex-direction: row;
    gap: 48px;
    background: #fff;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 48px 32px;
    margin-bottom: 32px;
    position: relative;
    align-items: center;
    justify-content: center;
}

.intro-left {
    flex: 1 1 50%;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    justify-content: center;
    min-width: 320px;
    max-width: 420px;
    padding-left: 12px;
}

.intro-title-row {
    display: flex;
    align-items: center;
    gap: 18px;
    margin-bottom: 18px;
}

.product-logo {
    width: 64px;
    height: 64px;
    border-radius: 16px;
    background: #fff;
    box-shadow: 0 2px 8px rgba(60,140,255,0.10);
    object-fit: cover;
    border: 2px solid #f2f2f2;
}

.intro-title-row h2 {
    margin: 0;
    font-size: 2rem;
    font-weight: bold;
}

.intro-desc p {
    font-size: 1.1rem;
    line-height: 1.8;
    margin-bottom: 18px;
    margin-top: 0;
}

.intro-image {
    flex: 1 1 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 260px;
    gap: 0;
}

    .intro-image img {
        max-width: 95%;
        max-height: 400px;
        border-radius: 18px;
        box-shadow: 0 4px 24px rgba(60,140,255,0.10);
        background: #f7f9fb;
        margin-right: 30px;
        display: block;
    }

        .intro-image img:last-child {
            margin-right: 0;
        }
/* 产品下载 */
.download-section {
    flex-direction: column;
    align-items: center;
    background: #fff;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 40px 24px 32px 24px;
    margin-bottom: 32px;
}

.download-title {
    font-size: 1.5rem;
    font-weight: bold;
    margin-bottom: 18px;
    color: var(--main-color);
}

.download-btns {
    display: flex;
    gap: 32px;
    margin-bottom: 12px;
}

.download-btn {
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 10px;
    background: var(--main-color);
    color: #fff;
    font-size: 1.1rem;
    font-weight: 500;
    border: none;
    border-radius: 12px;
    padding: 16px 36px;
    cursor: pointer;
    box-shadow: 0 2px 8px rgba(60,140,255,0.10);
    transition: background 0.2s, transform 0.2s;
}

    .download-btn:hover {
        background: #2566cc;
        transform: translateY(-2px) scale(1.04);
    }

    .download-btn img {
        width: 28px;
        height: 28px;
    }
/* 下载引导步骤 */
.steps-section {
    flex-direction: column;
    align-items: center;
    background: #fff;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 40px 24px 32px 24px;
    margin-bottom: 32px;
}

.steps-title {
    font-size: 1.5rem;
    font-weight: bold;
    margin-bottom: 24px;
    color: var(--main-color);
}

.steps-list {
    width: 100%;
    display: flex;
    flex-direction: column;
    gap: 32px;
}

.step-item {
    display: flex;
    align-items: center;
    background: #fff;
    border-radius: 18px;
    box-shadow: 0 8px 32px rgba(60,140,255,0.13);
    padding: 32px 24px;
    gap: 24px;
    margin-bottom: 0;
    transition: box-shadow 0.2s, transform 0.2s;
}

    .step-item:hover {
        box-shadow: 0 12px 40px rgba(60,140,255,0.18);
        transform: translateY(-2px) scale(1.01);
    }

.step-num-col {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin-right: 12px;
    min-width: 100px;
}

.step-badge {
    background: #3C8CFF;
    color: #fff;
    border-radius: 32px;
    padding: 10px 28px;
    font-weight: bold;
    font-size: 1.1rem;
    margin-bottom: 0;
    box-shadow: 0 2px 8px rgba(60,140,255,0.10);
    letter-spacing: 2px;
    display: flex;
    justify-content: space-around;
}

.step-img-large {
    width: 220px;
    min-width: 180px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0;
}

    .step-img-large img {
        width: 100%;
        border-radius: 14px;
        box-shadow: 0 2px 8px rgba(60,140,255,0.10);
        background: #f7f9fb;
        border: 1px solid #f0f0f0;
        display: block;
    }

.step-info {
    flex: 1;
    margin-left: 24px;
    display: flex;
    flex-direction: column;
    gap: 12px;
    word-break: break-all;
}

.step-title {
    font-size: 1.2rem;
    font-weight: bold;
    margin-bottom: 10px;
    color: #222;
}

.step-desc {
    font-size: 1rem;
    color: #555;
}
/* 关于我们 */
.about-section {
    flex-direction: column;
    align-items: center; /* 居中对齐 */
    text-align: center; /* 文本居中 */
    background: #fff;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    padding: 50px 32px;
    margin-bottom: 32px;
}

.about-title {
    font-size: 1.5rem;
    font-weight: bold;
    margin-bottom: 25px;
    color: var(--main-color);
}

.about-desc {
    font-size: 1.1rem;
    line-height: 1.8;
    margin-bottom: 25px;
}

.about-link {
    display: inline-block;
    background: var(--main-color);
    color: #fff;
    padding: 10px 24px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 500;
    transition: background 0.2s;
}

    .about-link:hover {
        background: #2566cc;
    }
/* Footer主样式 */
.main-footer {
    background: #3C8CFF;
    color: #fff;
    padding: 48px 0 18px 0;
    font-size: 1rem;
    margin-top: 48px;
}

    .main-footer .footer-content {
        max-width: 1200px;
        margin: 0 auto;
        display: flex;
        align-items: flex-start;
        justify-content: space-between;
        flex-wrap: wrap;
        gap: 32px;
    }

    .main-footer .footer-left {
        display: flex;
        flex-direction: column;
        align-items: center;
        min-width: 160px;
    }

    .main-footer .footer-logo {
        width: 48px;
        height: 48px;
        border-radius: 12px;
        margin-bottom: 10px;
        background: #fff;
    }

    .main-footer .footer-company {
        font-size: 1.3rem;
        font-weight: bold;
        margin-bottom: 8px;
    }

    .main-footer .footer-links {
        display: flex;
        gap: 48px;
        flex: 2;
        justify-content: center;
    }

    .main-footer .footer-col {
        display: flex;
        flex-direction: column;
        gap: 8px;
    }

    .main-footer .footer-title {
        font-weight: bold;
        margin-bottom: 8px;
    }

    .main-footer .footer-col a {
        color: #fff;
        opacity: 0.85;
        text-decoration: none;
        font-size: 1rem;
        transition: opacity 0.2s;
    }

        .main-footer .footer-col a:hover {
            opacity: 1;
            text-decoration: underline;
        }

    .main-footer .footer-qrcodes {
        display: flex;
        flex-direction: row;
        align-items: flex-start;
        gap: 48px;
        min-width: 120px;
        justify-content: flex-end;
    }

    .main-footer .qrcode-item {
        display: flex;
        flex-direction: column;
        align-items: center;
    }

        .main-footer .qrcode-item img {
            width: 80px;
            height: 80px;
            border-radius: 10px;
            background: #fff;
            margin-bottom: 8px;
        }

    .main-footer .qrcode-label {
        font-size: 1.05rem;
        color: #fff;
        opacity: 0.95;
        margin-top: 0;
    }

    .main-footer .footer-bottom {
        text-align: center;
        color: #e0eaff;
        font-size: 0.95rem;
        margin-top: 32px;
        display: flex;
        flex-direction: column;
        gap: 4px;
    }

.menu-toggle {
    display: none;
    background: none;
    border: none;
    outline: none;
    cursor: pointer;
    margin-left: auto;
    margin-right: 0;
    height: 40px;
    width: 48px;
    align-items: center;
    justify-content: center;
}

.menu-icon {
    display: block;
    width: 28px;
    height: 3px;
    background: #fff;
    border-radius: 2px;
    position: relative;
}

    .menu-icon::before,
    .menu-icon::after {
        content: '';
        display: block;
        width: 28px;
        height: 3px;
        background: #fff;
        border-radius: 2px;
        position: absolute;
        left: 0;
        transition: 0.2s;
    }

    .menu-icon::before {
        top: -9px;
    }

    .menu-icon::after {
        top: 9px;
    }

@media (max-width: 900px) {
    header {
        flex-direction: row;
        height: var(--nav-height);
        padding: 0 8px;
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        z-index: 100;
    }

    .menu-toggle {
        display: flex;
    }

    nav {
        position: absolute;
        top: var(--nav-height);
        right: 0;
        left: 0;
        background: var(--main-color);
        display: none;
        flex-direction: column;
        align-items: center;
        gap: 0;
        padding: 0;
        z-index: 99;
        max-height: 0;
        opacity: 0;
        overflow: hidden;
        pointer-events: none;
        transition: max-height 0.35s cubic-bezier(.4,0,.2,1), opacity 0.25s;
        box-shadow: 0 4px 24px rgba(60,140,255,0.08);
    }

        nav.open {
            display: flex;
            flex-direction: column;
            align-items: center;
            max-height: 400px;
            opacity: 1;
            pointer-events: auto;
        }

        nav a {
            width: auto;
            min-width: 120px;
            padding: 18px 28px;
            font-size: 18px;
            border-bottom: 1px solid rgba(255,255,255,0.08);
            text-align: center;
        }

    .company-name {
        font-size: 18px;
    }

    .product-intro {
        flex-direction: column;
        gap: 24px;
        padding: 24px 8px;
    }

    .intro-left, .intro-image {
        min-width: 0;
        width: 100%;
        padding: 0;
        max-width: 100%;
    }

    .intro-image {
        justify-content: flex-start;
        flex-wrap: wrap;
        gap: 12px;
    }

        .intro-image img {
            width: 100%;
            max-width: 100%;
            margin-right: 0;
            margin-bottom: 12px;
        }

            .intro-image img:last-child {
                margin-bottom: 0;
            }

    .download-section {
        padding: 18px 4px;
    }

    .download-btns {
        flex-direction: column;
        gap: 16px;
        align-items: stretch;
    }

    .download-btn {
        width: 100%;
        justify-content: center;
    }

    .steps-list {
        gap: 18px;
    }

    .step-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 12px;
        padding: 18px 8px;
    }

    .step-num-col, .step-img-large, .step-info {
        margin: 0;
        width: 100%;
    }

    .step-img-large {
        margin-bottom: 8px;
    }

        .step-img-large img {
            width: 100%;
            max-width: 100%;
        }

    .main-footer .footer-content {
        flex-direction: column;
        align-items: center;
        gap: 24px;
    }

    .main-footer .footer-links {
        flex-direction: column;
        gap: 18px;
        align-items: center;
    }

    .main-footer .footer-qrcodes {
        flex-direction: row;
        gap: 24px;
        justify-content: center;
    }
}

@media (max-width: 600px) {
    .intro-image, .step-img-large {
        display: flex;
        flex-direction: column;
        align-items: center;
        gap: 12px;
        width: 100%;
    }

        .intro-image img, .step-img-large img {
            width: 100%;
            max-width: 100%;
            height: auto;
            max-height: none;
            margin-right: 0;
            margin-bottom: 12px;
            display: block;
            box-sizing: border-box;
        }

            .intro-image img:last-child, .step-img-large img:last-child {
                margin-bottom: 0;
            }

    .main-footer .footer-qrcodes {
        flex-direction: column;
        align-items: center;
        gap: 18px;
    }

    .main-footer .qrcode-item img {
        width: 60px;
        height: 60px;
    }
}