:root {
    --primary: rgb(70,139,223);
    --primary-dark: #2566b8;
    --primary-soft: #edf5ff;
    --primary-pale: #f6fbff;
    --text: #1f2a37;
    --muted: #667085;
    --line: #dbe7f6;
    --card: #ffffff;
    --deep: #10233f;
    --radius: 18px;
    --shadow: 0 12px 32px rgba(37, 102, 184, 0.08);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    margin: 0;
    color: var(--text);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
    line-height: 1.72;
    background: linear-gradient(180deg, #f5faff 0%, #ffffff 32%, #f8fbff 100%);
    overflow-x: hidden;
}
a { color: var(--primary-dark); text-decoration: none; }
a:hover { color: var(--primary); }
img { max-width: 100%; height: auto; display: block; }

.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    background: rgba(255,255,255,0.92);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(219,231,246,0.8);
}
.header-inner {
    width: min(1160px, calc(100% - 32px));
    margin: 0 auto;
    min-height: 70px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
}
.brand { display: inline-flex; align-items: center; gap: 10px; color: var(--deep); font-weight: 800; }
.logo-img { width: 38px; height: 38px; border-radius: 12px; }
.brand-text { font-size: 18px; letter-spacing: 0.02em; }
.nav-toggle {
    width: 42px;
    height: 42px;
    display: inline-flex;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    padding: 0 10px;
    border: 1px solid var(--line);
    border-radius: 12px;
    background: #fff;
}
.nav-toggle span { height: 2px; background: var(--deep); border-radius: 999px; }
.site-nav {
    display: none;
    position: absolute;
    left: 16px;
    right: 16px;
    top: 70px;
    padding: 12px;
    border: 1px solid var(--line);
    border-radius: 18px;
    background: #fff;
    box-shadow: var(--shadow);
}
.site-nav.open { display: grid; gap: 8px; }
.site-nav a {
    padding: 10px 12px;
    border-radius: 12px;
    color: #344054;
    font-size: 15px;
}
.site-nav a.active,
.site-nav a:hover { background: var(--primary-soft); color: var(--primary-dark); }

.container { width: min(1160px, calc(100% - 32px)); margin: 0 auto; }
.narrow-container { width: min(920px, calc(100% - 32px)); margin: 0 auto; }
.section { padding: 56px 0; }
.section-title { margin: 0 0 18px; font-size: clamp(24px, 4vw, 34px); line-height: 1.25; color: var(--deep); }
.section-lead { margin: 0 0 26px; color: var(--muted); max-width: 760px; }
.eyebrow, .doc-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    margin-bottom: 12px;
    border-radius: 999px;
    color: var(--primary-dark);
    background: var(--primary-soft);
    font-size: 13px;
    font-weight: 700;
}

.docs-hero { padding: 44px 0 28px; }
.hero-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 28px;
    align-items: center;
}
.hero-copy h1, .page-hero h1, .doc-title h1 {
    margin: 0 0 16px;
    color: var(--deep);
    font-size: clamp(30px, 7vw, 54px);
    line-height: 1.12;
    letter-spacing: -0.03em;
}
.hero-copy p { margin: 0 0 22px; color: #4b5d75; font-size: 17px; }
.hero-tags { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 18px; }
.hero-tags span {
    padding: 8px 11px;
    border: 1px solid var(--line);
    border-radius: 999px;
    background: rgba(255,255,255,0.78);
    color: #35516f;
    font-size: 13px;
}
.hero-visual {
    position: relative;
    padding: 18px;
    border: 1px solid var(--line);
    border-radius: 28px;
    background: linear-gradient(145deg, #ffffff, #eef7ff);
    box-shadow: var(--shadow);
}
.app-frame {
    display: grid;
    place-items: center;
    min-height: 320px;
    border-radius: 24px;
    background: radial-gradient(circle at 50% 10%, rgba(70,139,223,0.18), transparent 38%), #f8fbff;
}
.app-frame img { width: min(260px, 72%); filter: drop-shadow(0 18px 30px rgba(37,102,184,0.16)); }
.security-stack { display: grid; gap: 12px; margin-top: 16px; }
.security-mini {
    padding: 14px;
    border: 1px solid var(--line);
    border-radius: 16px;
    background: rgba(255,255,255,0.82);
}
.security-mini strong { display: block; color: var(--deep); margin-bottom: 3px; }
.security-mini span { color: var(--muted); font-size: 14px; }

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 46px;
    padding: 12px 22px;
    border-radius: 999px;
    color: #fff;
    background: var(--primary);
    font-weight: 800;
    letter-spacing: 0.02em;
    box-shadow: 0 10px 22px rgba(70,139,223,0.22);
    transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
}
.download-btn:hover { color: #fff; background: var(--primary-dark); transform: translateY(-1px); box-shadow: 0 14px 26px rgba(70,139,223,0.26); }

.safety-strip {
    width: min(1160px, calc(100% - 32px));
    margin: 0 auto 20px;
    padding: 14px;
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    border: 1px solid #cfe4fb;
    border-radius: 18px;
    background: #eef7ff;
}
.safety-strip span { flex: 1 1 220px; color: #35516f; font-size: 14px; }

.docs-layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 22px;
    align-items: start;
}
.docs-sidebar {
    display: grid;
    gap: 8px;
    padding: 14px;
    border: 1px solid var(--line);
    border-radius: 20px;
    background: #fff;
    box-shadow: var(--shadow);
}
.docs-sidebar .sidebar-title { margin: 0 0 4px; color: var(--deep); font-weight: 800; }
.docs-sidebar a {
    display: block;
    padding: 10px 12px;
    border-radius: 12px;
    color: #46627d;
    background: #f9fcff;
}
.docs-sidebar a:hover { background: var(--primary-soft); color: var(--primary-dark); }
.docs-content { display: grid; gap: 28px; min-width: 0; }
.doc-section {
    padding: 22px;
    border: 1px solid var(--line);
    border-radius: 22px;
    background: rgba(255,255,255,0.92);
    box-shadow: var(--shadow);
}
.doc-section h2 { margin: 0 0 12px; color: var(--deep); font-size: clamp(22px, 4vw, 30px); line-height: 1.28; }
.doc-section p { color: #4b5d75; }

.docs-steps { display: grid; gap: 14px; }
.step-row {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 14px;
    padding: 16px;
    border: 1px solid var(--line);
    border-radius: 18px;
    background: #fbfdff;
}
.step-no {
    width: 42px;
    height: 42px;
    display: grid;
    place-items: center;
    border-radius: 14px;
    color: #fff;
    background: var(--primary);
    font-weight: 800;
}
.step-row h3 { margin: 0 0 6px; color: var(--deep); font-size: 18px; }
.step-row p { margin: 0 0 8px; }

.docs-category-grid, .feature-grid, .risk-grid, .faq-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 14px;
}
.category-card, .document-card, .feature-card, .risk-item, .faq-item, .security-panel {
    padding: 18px;
    border: 1px solid var(--line);
    border-radius: 18px;
    background: #fff;
    box-shadow: 0 8px 24px rgba(37,102,184,0.05);
}
.category-card h3, .feature-card h3, .risk-item h3, .faq-item h3 { margin: 0 0 8px; color: var(--deep); font-size: 18px; }
.category-card p, .feature-card p, .risk-item p, .faq-item p { margin: 0 0 10px; color: var(--muted); }
.card-link { font-weight: 800; color: var(--primary-dark); }

.principle-list { display: grid; gap: 12px; }
.principle-item {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 14px;
    padding: 16px;
    border-left: 4px solid var(--primary);
    border-radius: 16px;
    background: #f3f8ff;
}
.principle-num { color: var(--primary-dark); font-weight: 900; font-size: 20px; }
.principle-item strong { display: block; color: var(--deep); margin-bottom: 4px; }
.principle-item span { color: #53687f; }

.notice-box, .safety-notice {
    padding: 16px;
    border-left: 4px solid var(--primary);
    border-radius: 16px;
    background: var(--primary-soft);
    color: #35516f;
}
.notice-box strong, .safety-notice strong { color: var(--deep); }
.cta-section {
    padding: 34px 20px;
    border: 1px solid #cfe4fb;
    border-radius: 26px;
    background: linear-gradient(135deg, #f7fbff, #eaf5ff);
    text-align: center;
}
.cta-section h2 { margin: 0 0 10px; color: var(--deep); }
.cta-section p { margin: 0 auto 20px; max-width: 680px; color: var(--muted); }

.page-hero { padding: 46px 0 20px; }
.page-hero-card {
    padding: 26px;
    border: 1px solid var(--line);
    border-radius: 26px;
    background: linear-gradient(135deg, #ffffff, #eef7ff);
    box-shadow: var(--shadow);
}
.page-hero p { margin: 0; color: #4b5d75; max-width: 820px; }

.article-layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 22px;
    align-items: start;
}
.doc-article {
    padding: 24px;
    border: 1px solid var(--line);
    border-radius: 24px;
    background: #fff;
    box-shadow: var(--shadow);
}
.doc-article h2 { margin: 24px 0 10px; color: var(--deep); font-size: 24px; }
.doc-article p { color: #4b5d75; }
.article-summary {
    margin: 14px 0 22px;
    padding: 16px;
    border-radius: 18px;
    background: #f8fbff;
    border: 1px solid var(--line);
    color: #53687f;
}
.side-panel {
    padding: 18px;
    border: 1px solid var(--line);
    border-radius: 22px;
    background: #fff;
    box-shadow: var(--shadow);
}
.side-panel h3 { margin: 0 0 12px; color: var(--deep); }
.side-panel ul, .checklist, .plain-list { margin: 0; padding-left: 18px; color: #53687f; }
.side-panel li, .checklist li, .plain-list li { margin-bottom: 8px; }
.info-grid { display: grid; grid-template-columns: 1fr; gap: 12px; margin: 18px 0; }
.info-card { padding: 16px; border: 1px solid var(--line); border-radius: 18px; background: #fbfdff; }
.info-card strong { display: block; color: var(--deep); margin-bottom: 6px; }
.process-list { display: grid; gap: 12px; margin: 18px 0; }
.process-item { padding: 15px; border-radius: 16px; border: 1px solid var(--line); background: #fff; }
.process-item span { display: inline-flex; min-width: 34px; height: 34px; align-items: center; justify-content: center; border-radius: 12px; color: #fff; background: var(--primary); font-weight: 800; margin-right: 8px; }
.download-area { margin-top: 24px; }

.faq-list { display: grid; gap: 14px; }
.faq-block { padding: 18px; border: 1px solid var(--line); border-radius: 18px; background: #fff; }
.faq-block h2 { margin: 0 0 8px; font-size: 20px; color: var(--deep); }
.faq-block p { margin: 0; color: #4b5d75; }
.download-page-steps { counter-reset: item; display: grid; gap: 12px; margin: 22px 0; }
.download-page-steps li { list-style: none; padding: 16px; border: 1px solid var(--line); border-radius: 16px; background: #fbfdff; }

@media (min-width: 700px) {
    .docs-category-grid, .feature-grid, .risk-grid, .faq-grid, .info-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .security-stack { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}

@media (min-width: 960px) {
    .nav-toggle { display: none; }
    .site-nav { position: static; display: flex; align-items: center; gap: 4px; padding: 0; border: 0; border-radius: 0; background: transparent; box-shadow: none; }
    .site-nav a { padding: 9px 12px; }
    .docs-hero { padding-top: 74px; }
    .hero-grid { grid-template-columns: 1.02fr .98fr; gap: 46px; }
    .docs-layout { grid-template-columns: 250px 1fr; gap: 28px; }
    .docs-sidebar { position: sticky; top: 94px; }
    .docs-category-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
    .risk-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
    .feature-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
    .article-layout { grid-template-columns: minmax(0, 1fr) 300px; }
    .side-panel { position: sticky; top: 94px; }
    .doc-article { padding: 34px; }
}