:root {
    --primary: rgb(70,139,223);
    --primary-dark: #245fba;
    --primary-soft: #eef6ff;
    --primary-soft-2: #f6fbff;
    --ink: #122033;
    --muted: #61708a;
    --line: #d9e6f6;
    --card: #ffffff;
    --bg: #f7fbff;
    --success: #1f7a61;
    --warning: #9a6500;
    --radius: 18px;
    --shadow: 0 14px 34px rgba(31, 75, 130, .08);
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    min-width: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
    color: var(--ink);
    background: linear-gradient(180deg, #f4f9ff 0%, #ffffff 38%, #f7fbff 100%);
    line-height: 1.72;
    font-size: 16px;
}

a {
    color: var(--primary-dark);
    text-decoration: none;
}

a:hover {
    color: var(--primary);
}

img {
    max-width: 100%;
    height: auto;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    background: rgba(255, 255, 255, .94);
    border-bottom: 1px solid rgba(217, 230, 246, .9);
    backdrop-filter: blur(16px);
}

.header-inner,
.footer-inner,
.container {
    width: min(1120px, calc(100% - 32px));
    margin: 0 auto;
}

.header-inner {
    min-height: 68px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    color: var(--ink);
    font-weight: 800;
    letter-spacing: .02em;
}

.logo {
    width: 38px;
    height: 38px;
    border-radius: 12px;
    display: block;
}

.brand-text {
    font-size: 21px;
}

.nav-toggle {
    border: 1px solid var(--line);
    background: #fff;
    color: var(--ink);
    border-radius: 999px;
    padding: 8px 14px;
    font-size: 14px;
}

.site-nav {
    display: none;
    position: absolute;
    left: 16px;
    right: 16px;
    top: 72px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 18px;
    padding: 10px;
    box-shadow: var(--shadow);
}

.site-nav.is-open {
    display: grid;
    gap: 4px;
}

.site-nav a {
    color: #31415b;
    padding: 10px 12px;
    border-radius: 12px;
    font-weight: 600;
    font-size: 15px;
}

.site-nav a.active,
.site-nav a:hover {
    color: var(--primary-dark);
    background: var(--primary-soft);
}

main {
    overflow: hidden;
}

.docs-hero {
    width: min(1120px, calc(100% - 32px));
    margin: 28px auto 18px;
    display: grid;
    gap: 22px;
    align-items: center;
}

.hero-copy,
.hero-device,
.card,
.doc-card,
.category-card,
.security-panel,
.cta-section,
.page-hero,
.faq-item,
.side-note,
.content-panel {
    background: rgba(255, 255, 255, .92);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.hero-copy {
    padding: 28px;
}

.eyebrow,
.doc-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    width: fit-content;
    padding: 5px 11px;
    border-radius: 999px;
    color: var(--primary-dark);
    background: var(--primary-soft);
    border: 1px solid #cfe2fb;
    font-size: 13px;
    font-weight: 700;
}

h1,
h2,
h3 {
    color: var(--ink);
    line-height: 1.25;
    margin: 0 0 14px;
}

h1 {
    font-size: clamp(30px, 8vw, 54px);
    letter-spacing: -0.04em;
}

h2 {
    font-size: clamp(24px, 5vw, 34px);
    letter-spacing: -0.03em;
}

h3 {
    font-size: 19px;
}

p {
    margin: 0 0 14px;
    color: var(--muted);
}

.lead {
    font-size: 18px;
    color: #45566f;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 12px 22px;
    border-radius: 999px;
    background: var(--primary);
    color: #fff;
    font-weight: 800;
    box-shadow: 0 10px 22px rgba(70, 139, 223, .22);
    border: 1px solid rgba(70,139,223,.4);
    transition: transform .18s ease, box-shadow .18s ease, background .18s ease;
}

.download-btn:hover {
    color: #fff;
    background: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: 0 14px 28px rgba(70, 139, 223, .26);
}

.security-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 18px;
}

.security-tags span {
    padding: 8px 11px;
    color: #28425f;
    background: #f8fbff;
    border: 1px solid var(--line);
    border-radius: 999px;
    font-size: 13px;
    font-weight: 700;
}

.hero-device {
    padding: 22px;
    background: radial-gradient(circle at 20% 20%, #e7f3ff, #ffffff 44%, #f3f8ff 100%);
}

.device-frame {
    display: grid;
    gap: 16px;
}

.app-image-wrap {
    border-radius: 26px;
    background: linear-gradient(145deg, #ffffff, #eaf4ff);
    border: 1px solid #d8e8fa;
    padding: 18px;
    display: flex;
    justify-content: center;
}

.app-image-wrap img {
    border-radius: 24px;
    max-height: 420px;
    object-fit: contain;
}

.status-grid {
    display: grid;
    gap: 10px;
}

.status-card {
    border-radius: 16px;
    border: 1px solid var(--line);
    background: rgba(255,255,255,.78);
    padding: 14px;
}

.status-card strong {
    display: block;
    color: #1e3653;
    margin-bottom: 4px;
}

.safety-strip {
    width: min(1120px, calc(100% - 32px));
    margin: 16px auto 34px;
    display: grid;
    gap: 10px;
    padding: 14px;
    border-radius: 18px;
    background: #edf6ff;
    border: 1px solid #cde5ff;
}

.safety-strip span {
    color: #295075;
    font-weight: 700;
}

.docs-layout {
    width: min(1120px, calc(100% - 32px));
    margin: 0 auto 44px;
    display: grid;
    gap: 20px;
}

.docs-sidebar {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 14px;
    box-shadow: var(--shadow);
}

.docs-sidebar strong {
    display: block;
    margin-bottom: 10px;
}

.docs-sidebar nav {
    display: grid;
    gap: 6px;
}

.docs-sidebar a {
    display: block;
    border-radius: 12px;
    padding: 9px 10px;
    color: #40516b;
    background: #f7fbff;
    border: 1px solid transparent;
    font-weight: 700;
}

.docs-sidebar a:hover {
    border-color: #cfe3fb;
    background: var(--primary-soft);
}

.docs-content {
    display: grid;
    gap: 22px;
}

.section,
.content-panel {
    padding: 24px;
}

.section-title {
    display: flex;
    align-items: baseline;
    gap: 12px;
    margin-bottom: 14px;
}

.section-title span {
    color: var(--primary);
    font-weight: 900;
    letter-spacing: .1em;
    font-size: 13px;
}

.docs-steps {
    display: grid;
    gap: 12px;
    counter-reset: step;
}

.step-item {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 13px;
    padding: 16px;
    border: 1px solid var(--line);
    border-radius: 16px;
    background: #fff;
}

.step-num {
    width: 38px;
    height: 38px;
    display: grid;
    place-items: center;
    border-radius: 12px;
    background: var(--primary-soft);
    color: var(--primary-dark);
    font-weight: 900;
}

.docs-category-grid,
.feature-grid,
.risk-grid,
.faq-grid,
.card-grid {
    display: grid;
    gap: 14px;
}

.category-card,
.doc-card,
.card,
.faq-item {
    padding: 18px;
}

.category-card,
.doc-card {
    display: grid;
    gap: 8px;
}

.category-card small,
.doc-card small {
    color: var(--primary-dark);
    font-weight: 800;
}

.link-line {
    font-weight: 800;
}

.principle-list {
    display: grid;
    gap: 12px;
}

.principle-item {
    display: grid;
    gap: 8px;
    padding: 16px;
    border-radius: 16px;
    background: #f8fbff;
    border: 1px solid var(--line);
}

.principle-num {
    color: var(--primary);
    font-weight: 900;
}

.notice,
.tip-box,
.warn-box,
.checklist {
    border-radius: 16px;
    padding: 16px;
    margin: 16px 0;
    border: 1px solid #cfe2fb;
    background: #f2f8ff;
    border-left: 4px solid var(--primary);
}

.warn-box {
    background: #fff9ef;
    border-color: #f2dfba;
    border-left-color: #e9a23b;
}

.checklist ul,
.notice ul,
.tip-box ul,
.warn-box ul,
ul.clean-list {
    padding-left: 20px;
    margin: 8px 0 0;
    color: var(--muted);
}

.risk-item {
    padding: 18px;
    border: 1px solid var(--line);
    border-radius: 16px;
    background: #fff;
}

.risk-item strong {
    display: block;
    color: #233b59;
    margin-bottom: 6px;
}

.cta-section {
    width: min(1120px, calc(100% - 32px));
    margin: 30px auto 52px;
    padding: 30px 22px;
    text-align: center;
    background: linear-gradient(135deg, #ffffff 0%, #edf6ff 100%);
}

.cta-section p {
    max-width: 680px;
    margin-left: auto;
    margin-right: auto;
}

.page-hero {
    width: min(960px, calc(100% - 32px));
    margin: 30px auto 20px;
    padding: 28px;
    background: linear-gradient(135deg, #ffffff 0%, #f0f7ff 100%);
}

.page-layout {
    width: min(1080px, calc(100% - 32px));
    margin: 0 auto 46px;
    display: grid;
    gap: 20px;
}

.article-card {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 24px;
    box-shadow: var(--shadow);
}

.article-card h2 {
    margin-top: 24px;
}

.article-card h2:first-child {
    margin-top: 0;
}

.side-note {
    padding: 18px;
    align-self: start;
}

.side-note h3 {
    margin-bottom: 10px;
}

.side-note a {
    display: block;
    padding: 9px 0;
    border-bottom: 1px solid var(--line);
    font-weight: 700;
}

.side-note a:last-child {
    border-bottom: 0;
}

.operation-list {
    display: grid;
    gap: 12px;
    margin: 18px 0;
}

.operation-list li {
    list-style: none;
    padding: 14px 14px 14px 48px;
    border: 1px solid var(--line);
    border-radius: 15px;
    background: #f9fcff;
    position: relative;
    color: #53637a;
}

.operation-list li::before {
    content: counter(item);
    counter-increment: item;
    position: absolute;
    left: 14px;
    top: 14px;
    width: 24px;
    height: 24px;
    display: grid;
    place-items: center;
    border-radius: 8px;
    background: var(--primary-soft);
    color: var(--primary-dark);
    font-weight: 900;
    font-size: 13px;
}

.operation-list {
    counter-reset: item;
    padding: 0;
}

.download-panel {
    margin-top: 22px;
    padding-top: 18px;
    border-top: 1px solid var(--line);
}

.download-page-grid {
    display: grid;
    gap: 16px;
}

.faq-list {
    display: grid;
    gap: 14px;
}

.faq-item h2,
.faq-item h3 {
    font-size: 19px;
    margin-bottom: 8px;
}

.site-footer {
    border-top: 1px solid var(--line);
    background: #ffffff;
    padding: 30px 0;
}

.footer-inner {
    display: grid;
    gap: 18px;
}

.footer-brand {
    font-weight: 900;
    color: var(--ink);
    margin-bottom: 6px;
}

.footer-links {
    display: grid;
    gap: 8px;
}

.footer-links a {
    color: #40516b;
    font-weight: 700;
}

@media (min-width: 640px) {
    .docs-category-grid,
    .feature-grid,
    .risk-grid,
    .faq-grid,
    .card-grid,
    .download-page-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .safety-strip {
        grid-template-columns: repeat(3, 1fr);
    }

    .footer-inner {
        grid-template-columns: 1.2fr .8fr;
        align-items: start;
    }
}

@media (min-width: 900px) {
    .nav-toggle {
        display: none;
    }

    .site-nav {
        display: flex;
        position: static;
        box-shadow: none;
        border: 0;
        background: transparent;
        padding: 0;
        gap: 4px;
        align-items: center;
    }

    .site-nav a {
        padding: 8px 12px;
    }

    .docs-hero {
        grid-template-columns: 1.05fr .95fr;
        margin-top: 46px;
    }

    .hero-copy {
        padding: 42px;
    }

    .device-frame {
        grid-template-columns: .95fr 1.05fr;
        align-items: center;
    }

    .docs-layout {
        grid-template-columns: 250px minmax(0, 1fr);
        align-items: start;
    }

    .docs-sidebar {
        position: sticky;
        top: 90px;
    }

    .docs-category-grid,
    .feature-grid,
    .risk-grid {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }

    .page-layout {
        grid-template-columns: minmax(0, 1fr) 280px;
        align-items: start;
    }

    .page-hero {
        padding: 38px;
    }

    .article-card {
        padding: 34px;
    }

    .principle-item {
        grid-template-columns: 76px minmax(0, 1fr);
        align-items: start;
    }

    .principle-num {
        font-size: 24px;
    }
}

@media (min-width: 1100px) {
    .docs-steps .step-item {
        grid-template-columns: 48px minmax(0, 1fr) auto;
    }
}