:root {
    --primary: rgb(70,139,223);
    --primary-dark: #1f5fba;
    --primary-soft: #eef6ff;
    --ink: #102033;
    --muted: #5d6d80;
    --line: #dbe8f7;
    --panel: #ffffff;
    --bg: #f7fbff;
    --warning: #fff8e7;
    --success: #eefbf6;
    --radius: 18px;
    --shadow: 0 16px 40px rgba(36, 91, 151, .09);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    margin: 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, #f6fbff 0%, #ffffff 38%, #f7fbff 100%);
    line-height: 1.75;
    overflow-x: hidden;
}
a { color: var(--primary-dark); text-decoration: none; }
a:hover { color: var(--primary); }
img { max-width: 100%; display: block; }
.container { width: min(100% - 32px, 1180px); margin: 0 auto; }
.narrow-container { width: min(100% - 32px, 940px); margin: 0 auto; }

.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    background: rgba(255,255,255,.92);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(219,232,247,.9);
}
.nav-wrap {
    min-height: 72px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}
.logo { display: flex; align-items: center; gap: 10px; font-weight: 800; color: var(--ink); letter-spacing: .2px; }
.logo img { width: 38px; height: 38px; border-radius: 12px; }
.site-nav { display: none; flex-direction: column; width: 100%; padding: 12px 0 18px; gap: 6px; }
.site-nav a { color: #23374f; padding: 10px 12px; border-radius: 12px; font-size: 15px; }
.site-nav a:hover { background: var(--primary-soft); }
.site-nav.is-open { display: flex; position: absolute; left: 0; top: 72px; background: #fff; border-bottom: 1px solid var(--line); padding-left: 16px; padding-right: 16px; box-shadow: var(--shadow); }
.nav-toggle { width: 42px; height: 42px; border: 1px solid var(--line); background: #fff; border-radius: 12px; display: inline-flex; flex-direction: column; justify-content: center; align-items: center; gap: 5px; }
.nav-toggle span { width: 20px; height: 2px; background: var(--ink); border-radius: 2px; }

.section { padding: 58px 0; }
.section-title { margin: 0 0 18px; font-size: clamp(24px, 4vw, 36px); line-height: 1.25; }
.section-lead { color: var(--muted); margin: 0 0 28px; }
.eyebrow, .doc-badge { display: inline-flex; align-items: center; gap: 6px; padding: 6px 12px; border-radius: 999px; background: var(--primary-soft); color: var(--primary-dark); font-size: 13px; font-weight: 700; margin-bottom: 14px; }

.docs-hero {
    padding: 54px 0 34px;
    background: radial-gradient(circle at 80% 10%, rgba(70,139,223,.17), transparent 34%), linear-gradient(135deg, #ffffff 0%, #f2f8ff 100%);
}
.hero-grid { display: grid; gap: 28px; align-items: center; }
.hero-copy h1 { margin: 0 0 16px; font-size: clamp(34px, 8vw, 62px); line-height: 1.12; letter-spacing: -1.8px; }
.hero-copy p { color: #40566f; font-size: 17px; margin: 0 0 24px; }
.hero-tags { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 20px; }
.hero-tags span { padding: 7px 11px; border: 1px solid var(--line); border-radius: 999px; background: rgba(255,255,255,.78); color: #2a4867; font-size: 13px; }
.hero-visual { position: relative; display: grid; gap: 14px; }
.app-card { background: rgba(255,255,255,.86); border: 1px solid rgba(219,232,247,.95); border-radius: 28px; padding: 20px; box-shadow: var(--shadow); }
.app-card img { margin: 0 auto; border-radius: 24px; }
.status-card { background: #fff; border: 1px solid var(--line); border-radius: 18px; padding: 16px; box-shadow: 0 10px 28px rgba(70,139,223,.08); }
.status-card strong { display: block; color: var(--primary-dark); margin-bottom: 4px; }
.status-grid { display: grid; gap: 12px; margin-top: 14px; }

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 46px;
    padding: 12px 24px;
    border-radius: 999px;
    background: var(--primary);
    color: #fff !important;
    font-weight: 800;
    letter-spacing: .2px;
    border: 1px solid rgba(70,139,223,.15);
    box-shadow: 0 12px 26px rgba(70,139,223,.22);
    cursor: pointer;
}
.download-btn:hover { background: var(--primary-dark); transform: translateY(-1px); }

.safety-strip { padding: 18px 0; background: rgba(238,246,255,.9); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.safety-strip-inner { display: grid; gap: 10px; }
.safety-strip span { padding-left: 16px; position: relative; color: #2c4865; }
.safety-strip span::before { content: ""; width: 7px; height: 7px; border-radius: 50%; background: var(--primary); position: absolute; left: 0; top: 12px; }

.docs-layout { display: grid; gap: 26px; align-items: start; }
.docs-sidebar { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 16px; box-shadow: 0 10px 26px rgba(31,95,186,.05); }
.docs-sidebar h2 { font-size: 16px; margin: 0 0 12px; }
.docs-sidebar nav { display: grid; gap: 8px; }
.docs-sidebar a { display: block; padding: 10px 12px; border-radius: 12px; color: #31506e; background: #f8fbff; border: 1px solid transparent; }
.docs-sidebar a:hover { border-color: var(--line); background: var(--primary-soft); }
.docs-main { display: grid; gap: 28px; min-width: 0; }
.doc-section { background: rgba(255,255,255,.92); border: 1px solid var(--line); border-radius: 22px; padding: 24px; box-shadow: 0 12px 30px rgba(36,91,151,.06); }
.doc-section h2 { margin: 0 0 12px; font-size: clamp(22px, 4vw, 30px); }
.doc-section h3 { margin-top: 0; }
.doc-muted { color: var(--muted); }

.docs-steps { display: grid; gap: 14px; counter-reset: step; }
.step-card { display: grid; gap: 10px; padding: 18px; border: 1px solid var(--line); border-radius: 16px; background: #fbfdff; }
.step-number { width: 38px; height: 38px; display: inline-flex; align-items: center; justify-content: center; border-radius: 12px; background: var(--primary); color: #fff; font-weight: 800; }
.step-card h3 { margin: 0; font-size: 18px; }
.step-card p { margin: 0; color: var(--muted); }
.step-card a { font-weight: 700; }

.docs-category-grid, .risk-grid, .feature-grid, .faq-grid, .info-grid { display: grid; gap: 16px; }
.category-card, .document-card, .risk-item, .faq-item, .security-panel, .info-card {
    background: #fff;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 18px;
    box-shadow: 0 10px 24px rgba(36,91,151,.05);
}
.category-card h3, .document-card h3, .risk-item h3, .faq-item h3, .security-panel h3, .info-card h3 { margin: 0 0 8px; }
.category-card p, .document-card p, .risk-item p, .faq-item p, .security-panel p, .info-card p { color: var(--muted); margin: 0 0 12px; }
.category-card a, .document-card a, .risk-item a { font-weight: 800; }

.principle-list { display: grid; gap: 14px; }
.principle-item { display: grid; grid-template-columns: auto 1fr; gap: 14px; align-items: start; padding: 16px; background: #fbfdff; border: 1px solid var(--line); border-radius: 16px; }
.principle-index { width: 36px; height: 36px; border-radius: 12px; background: var(--primary-soft); color: var(--primary-dark); display: inline-flex; align-items: center; justify-content: center; font-weight: 800; }
.principle-item h3 { margin: 0 0 6px; font-size: 17px; }
.principle-item p { margin: 0; color: var(--muted); }

.notice-box, .tip-box, .checklist-box {
    border-left: 4px solid var(--primary);
    background: var(--primary-soft);
    border-radius: 14px;
    padding: 16px 18px;
    color: #294765;
    margin: 18px 0;
}
.notice-box strong, .tip-box strong { color: var(--primary-dark); }
.checklist { padding-left: 20px; margin: 10px 0 0; }
.checklist li { margin: 8px 0; }

.cta-section { text-align: center; border-radius: 28px; padding: 36px 20px; background: linear-gradient(135deg, #eef6ff 0%, #ffffff 100%); border: 1px solid var(--line); }
.cta-section h2 { margin: 0 0 10px; font-size: clamp(24px, 5vw, 38px); }
.cta-section p { margin: 0 auto 22px; max-width: 680px; color: var(--muted); }

.page-hero { padding: 52px 0 26px; background: linear-gradient(135deg, #fff 0%, #eef6ff 100%); border-bottom: 1px solid var(--line); }
.page-hero h1 { margin: 0 0 14px; font-size: clamp(30px, 7vw, 48px); line-height: 1.18; letter-spacing: -1px; }
.page-hero p { color: var(--muted); margin: 0; max-width: 760px; }
.doc-page-layout { display: grid; gap: 24px; align-items: start; }
.article-card { background: #fff; border: 1px solid var(--line); border-radius: 22px; padding: 24px; box-shadow: var(--shadow); }
.article-card h2 { margin-top: 28px; }
.article-card h2:first-child { margin-top: 0; }
.aside-panel { background: #fff; border: 1px solid var(--line); border-radius: 18px; padding: 18px; }
.aside-panel h2, .aside-panel h3 { margin-top: 0; }
.aside-panel a { display: block; padding: 10px 0; border-bottom: 1px solid #edf3fb; font-weight: 700; }
.aside-panel a:last-child { border-bottom: 0; }

.download-steps { display: grid; gap: 12px; margin: 24px 0; }
.download-step { display: flex; gap: 12px; align-items: flex-start; padding: 14px; border: 1px solid var(--line); border-radius: 16px; background: #fbfdff; }
.download-step span { flex: 0 0 auto; width: 30px; height: 30px; border-radius: 10px; background: var(--primary); color: #fff; display: inline-flex; align-items: center; justify-content: center; font-weight: 800; }
.download-step p { margin: 0; color: var(--muted); }

.site-footer { margin-top: 58px; background: #0f2238; color: #d8e5f5; padding: 44px 0 18px; }
.footer-grid { display: grid; gap: 24px; }
.footer-logo { color: #fff; font-weight: 900; font-size: 20px; margin-bottom: 8px; }
.site-footer h3 { color: #fff; margin: 0 0 10px; }
.site-footer a { display: block; color: #d8e5f5; margin: 8px 0; }
.site-footer p { color: #b8c9da; margin: 0; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.12); margin-top: 28px; padding-top: 18px; font-size: 13px; color: #a8bbce; }

@media (min-width: 720px) {
    .docs-category-grid, .risk-grid, .feature-grid, .faq-grid, .info-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .safety-strip-inner { grid-template-columns: repeat(3, minmax(0, 1fr)); }
    .footer-grid { grid-template-columns: 1.3fr .8fr 1fr; }
    .download-steps { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (min-width: 980px) {
    .nav-toggle { display: none; }
    .site-nav { display: flex; flex-direction: row; width: auto; padding: 0; gap: 2px; }
    .site-nav.is-open { position: static; box-shadow: none; border: 0; padding: 0; }
    .hero-grid { grid-template-columns: 1.02fr .98fr; gap: 46px; }
    .status-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
    .docs-layout { grid-template-columns: 250px minmax(0, 1fr); }
    .docs-sidebar { position: sticky; top: 92px; }
    .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)); }
    .doc-page-layout { grid-template-columns: minmax(0, 1fr) 300px; }
    .article-card { padding: 34px; }
    .step-card { grid-template-columns: auto 1fr auto; align-items: center; }
}

@media (max-width: 420px) {
    .container, .narrow-container { width: min(100% - 24px, 1180px); }
    .doc-section, .article-card { padding: 18px; }
    .download-btn { width: 100%; }
    .hero-copy h1 { letter-spacing: -1px; }
}