:root {
  color-scheme: light;
  --ink: #152c46;
  --muted: #60738c;
  --brand: #245fce;
  --brand-dark: #164397;
  --line: #dce6f3;
  --soft: #f3f7fd;
  --paper: #ffffff;
  --warm: #f8f4e9;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background:
    radial-gradient(circle at 8% 0%, #edf3ff 0, transparent 28rem),
    linear-gradient(180deg, #fbfdff 0, #f7f9fc 52%, #fff 100%);
  color: var(--ink);
  font-family: "Microsoft YaHei", "PingFang SC", system-ui, sans-serif;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--brand-dark); text-underline-offset: 3px; }
a:hover { color: var(--brand); }

.site-header,
main,
.site-footer {
  width: min(1120px, calc(100% - 48px));
  margin-inline: auto;
}

.site-header {
  min-height: 72px;
  display: flex;
  align-items: center;
  gap: 34px;
  border-bottom: 1px solid #e7eef7;
}

.site-brand {
  flex: none;
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  text-decoration: none;
}

.site-brand img {
  width: 42px;
  height: 42px;
  border-radius: 12px;
}

.site-brand strong {
  display: block;
  font-size: 21px;
  line-height: 1.2;
  letter-spacing: -.02em;
}

.site-brand small {
  display: block;
  margin-top: 4px;
  color: #71839a;
  font-size: 10px;
  line-height: 1;
  letter-spacing: .08em;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 26px;
  margin-left: auto;
}

.site-nav a {
  color: #50657f;
  font-size: 13px;
  font-weight: 600;
  text-decoration: none;
}

.site-nav a[aria-current="page"] { color: var(--brand-dark); }
.site-nav .nav-workbench { color: var(--brand-dark); }

.menu-toggle {
  display: none;
  margin-left: auto;
  padding: 7px 11px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  color: var(--ink);
  font: inherit;
  font-size: 12px;
}

main { padding-block: 22px 52px; }

.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 18px;
  color: #7a8aa0;
  font-size: 12px;
}

.breadcrumb a { color: #607897; text-decoration: none; }
.breadcrumb span { color: #a4b0bf; }

.guide-hero {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) minmax(250px, .64fr);
  gap: 34px;
  padding: clamp(28px, 3.5vw, 42px);
  overflow: hidden;
  border: 1px solid #dbe7f8;
  border-radius: 16px;
  background:
    linear-gradient(120deg, rgba(255,255,255,.98), rgba(242,247,255,.96)),
    repeating-linear-gradient(90deg, transparent 0 47px, #e3ebf8 48px);
  box-shadow: 0 10px 35px rgba(39, 75, 128, .06);
}

.guide-hero::after {
  content: "";
  position: absolute;
  right: -110px;
  bottom: -165px;
  width: 320px;
  height: 320px;
  border: 44px solid rgba(37, 99, 235, .045);
  border-radius: 50%;
  pointer-events: none;
}

.eyebrow {
  margin: 0 0 10px;
  color: var(--brand);
  font-size: 11px;
  font-weight: 800;
  letter-spacing: .13em;
}

h1 {
  max-width: 17ch;
  margin: 0;
  font-size: clamp(34px, 4vw, 48px);
  line-height: 1.2;
  letter-spacing: -.038em;
}

.hero-intro {
  max-width: 660px;
  margin: 14px 0 0;
  color: #536982;
  font-size: 16px;
  line-height: 1.75;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 11px;
  margin-top: 20px;
}

.primary-link,
.secondary-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  padding: 8px 17px;
  border-radius: 9px;
  font-size: 13px;
  font-weight: 700;
  text-decoration: none;
}

.primary-link {
  background: var(--brand);
  color: #fff;
  box-shadow: 0 7px 18px rgba(36, 95, 206, .2);
}

.primary-link:hover { color: #fff; background: var(--brand-dark); }

.secondary-link {
  border: 1px solid #cfddef;
  background: rgba(255,255,255,.8);
  color: #35577e;
}

.hero-note {
  position: relative;
  z-index: 1;
  align-self: center;
  padding: 18px 20px;
  border: 1px solid #dde7f4;
  border-radius: 12px;
  background: rgba(255,255,255,.9);
}

.hero-note small {
  color: #73869e;
  font-size: 10px;
  font-weight: 700;
  letter-spacing: .08em;
}

.hero-note strong {
  display: block;
  margin: 7px 0 6px;
  font-size: 16px;
  line-height: 1.45;
}

.hero-note p {
  margin: 0;
  color: var(--muted);
  font-size: 11px;
  line-height: 1.7;
}

.chapter-nav {
  display: flex;
  gap: 8px;
  padding: 8px;
  margin: 12px 0 22px;
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: 11px;
  background: rgba(255,255,255,.8);
}

.chapter-nav a {
  flex: none;
  padding: 6px 11px;
  border-radius: 7px;
  color: #506783;
  font-size: 12px;
  font-weight: 600;
  text-decoration: none;
}

.chapter-nav a:hover { background: #edf4ff; color: var(--brand-dark); }

.guide-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 230px;
  gap: 24px;
  align-items: start;
}

.guide-content {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: var(--paper);
  box-shadow: 0 8px 28px rgba(43, 75, 112, .035);
}

.guide-section {
  scroll-margin-top: 20px;
  padding: clamp(24px, 3.2vw, 34px);
  border: 0;
  border-bottom: 1px solid #e7edf5;
  border-radius: 0;
  background: transparent;
  box-shadow: none;
}

.guide-section:last-child { border-bottom: 0; }

.section-index {
  color: #92a6bd;
  font-size: 10px;
  font-weight: 800;
  letter-spacing: .12em;
}

.guide-section h2,
.related-section h2,
.about-section h2 {
  margin: 6px 0 11px;
  font-size: clamp(21px, 2.4vw, 26px);
  line-height: 1.38;
  letter-spacing: -.025em;
}

.guide-section h3 {
  margin: 25px 0 8px;
  font-size: 16px;
  line-height: 1.55;
}

.guide-section p {
  margin: 0 0 11px;
  color: #52677f;
  font-size: 15px;
  line-height: 1.78;
}

.guide-section p:last-child { margin-bottom: 0; }

.check-list,
.step-list {
  display: grid;
  gap: 8px;
  padding: 0;
  margin: 15px 0 0;
  list-style: none;
}

.check-list li,
.step-list li {
  position: relative;
  padding-left: 28px;
  color: #4b617a;
  font-size: 14px;
  line-height: 1.75;
}

.check-list li::before {
  content: "✓";
  position: absolute;
  left: 0;
  top: 2px;
  display: grid;
  place-items: center;
  width: 18px;
  height: 18px;
  border-radius: 6px;
  background: #e9f1ff;
  color: var(--brand);
  font-size: 11px;
  font-weight: 800;
}

.step-list { counter-reset: step; }
.step-list li { counter-increment: step; padding-left: 36px; }

.step-list li::before {
  content: counter(step, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 1px;
  color: var(--brand);
  font-size: 11px;
  font-weight: 800;
}

.data-table {
  width: 100%;
  margin-top: 15px;
  border-collapse: collapse;
  font-size: 14px;
}

.data-table th,
.data-table td {
  padding: 9px 11px;
  border-bottom: 1px solid #e9eef5;
  text-align: left;
  vertical-align: top;
}

.data-table th { color: #375474; background: #f6f9fd; }
.data-table td { color: #5b6d82; }
.data-table tr:last-child td { border-bottom: 0; }

.callout {
  margin-top: 15px;
  padding: 13px 15px;
  border-left: 3px solid #e2af45;
  border-radius: 0 10px 10px 0;
  background: var(--warm);
  color: #725d32;
  font-size: 13px;
}

.side-panel {
  position: sticky;
  top: 18px;
  display: grid;
  gap: 11px;
}

.toc,
.side-card {
  padding: 17px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(255,255,255,.88);
}

.toc > strong,
.side-card > strong {
  display: block;
  margin-bottom: 8px;
  font-size: 12px;
  letter-spacing: .05em;
}

.toc a {
  display: block;
  padding: 6px 0;
  border-bottom: 1px solid #edf1f6;
  color: #5a7089;
  font-size: 13px;
  text-decoration: none;
}

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

.side-card p {
  margin: 0;
  color: #667b91;
  font-size: 12px;
  line-height: 1.8;
}

.side-card .primary-link {
  width: 100%;
  margin-top: 13px;
  font-size: 12px;
}

.related-section {
  margin-top: 34px;
  padding-top: 25px;
  border-top: 1px solid var(--line);
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}

.related-grid a {
  display: block;
  min-height: 116px;
  padding: 17px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: #fff;
  color: var(--ink);
  text-decoration: none;
  transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease;
}

.related-grid a:hover {
  transform: translateY(-2px);
  border-color: #c6d8ef;
  box-shadow: 0 12px 28px rgba(43, 75, 112, .08);
}

.related-grid strong { display: block; font-size: 16px; }
.related-grid p { margin: 8px 0 0; color: var(--muted); font-size: 13px; line-height: 1.7; }

.guide-hero-directory {
  min-height: 0;
  padding-block: clamp(28px, 4vw, 46px);
}

.compact-note { align-self: center; }

.guide-directory {
  margin-top: 22px;
  padding: clamp(24px, 3.2vw, 34px);
  border: 1px solid var(--line);
  border-radius: 16px;
  background: #fff;
}

.guide-directory > header h2 {
  margin: 5px 0 5px;
  font-size: clamp(21px, 2.5vw, 28px);
}

.guide-directory > header p {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
}

.guide-directory-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin-top: 20px;
}

.guide-directory-card {
  position: relative;
  display: flex;
  min-height: 175px;
  flex-direction: column;
  padding: 18px;
  border: 1px solid #e0e8f2;
  border-radius: 12px;
  background: #fafcff;
  color: var(--ink);
  text-decoration: none;
  transition: border-color .18s ease, transform .18s ease, box-shadow .18s ease;
}

.guide-directory-card:hover {
  transform: translateY(-2px);
  border-color: #c5d7ee;
  box-shadow: 0 10px 22px rgba(46, 79, 120, .07);
}

.guide-directory-card.featured {
  background: linear-gradient(145deg, #eff5ff, #fbfdff);
  border-color: #d5e3f7;
}

.guide-card-index {
  color: #91a8c2;
  font-size: 10px;
  font-weight: 800;
}

.guide-directory-card > div { margin-top: 15px; }
.guide-directory-card small { color: #6f86a1; font-size: 12px; font-weight: 650; }
.guide-directory-card h3 { margin: 4px 0 8px; font-size: 20px; line-height: 1.35; }
.guide-directory-card p { margin: 0; color: #657a91; font-size: 13px; line-height: 1.72; }
.guide-directory-card b { margin-top: auto; padding-top: 17px; color: var(--brand); font-size: 12px; }

.guide-principles {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin-top: 16px;
}

.guide-principles article {
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: #fff;
}

.guide-principles span { color: #98a9be; font-size: 9px; font-weight: 800; }
.guide-principles strong { display: block; margin-top: 5px; font-size: 15px; }
.guide-principles p { margin: 5px 0 0; color: var(--muted); font-size: 12px; line-height: 1.7; }

.site-footer {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 9px 18px;
  padding-block: 20px 30px;
  border-top: 1px solid var(--line);
  color: #7a8da3;
  font-size: 11px;
}

.site-footer .footer-brand { color: #3d5877; font-weight: 700; }
.site-footer .footer-links { display: flex; flex-wrap: wrap; gap: 18px; margin-left: auto; }
.site-footer a { color: #617a97; text-decoration: none; }

.about-hero { grid-template-columns: 1fr 360px; }
.about-hero h1 { max-width: 19ch; }
.about-topics { display: grid; gap: 18px; }
.about-section { padding: 30px; border: 1px solid var(--line); border-radius: 18px; background: #fff; }
.about-section p { color: #566b82; }
.principle-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 13px; margin-top: 20px; }
.principle-grid article { padding: 18px; border-radius: 13px; background: #f5f8fd; }
.principle-grid strong { display: block; margin-bottom: 6px; font-size: 14px; }
.principle-grid p { margin: 0; font-size: 12px; }

a:focus-visible,
button:focus-visible {
  outline: 3px solid #8eb6fa;
  outline-offset: 3px;
}

@media (max-width: 900px) {
  .guide-hero,
  .about-hero { grid-template-columns: 1fr; }
  .hero-note { max-width: 520px; }
  .guide-layout { grid-template-columns: 1fr; }
  .side-panel { position: static; grid-template-columns: 1fr 1fr; }
  .toc { grid-row: span 2; }
  .principle-grid { grid-template-columns: 1fr; }
  .guide-directory-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 700px) {
  .site-header,
  main,
  .site-footer { width: min(calc(100% - 28px), 1180px); }
  .site-header { position: relative; min-height: 72px; }
  .menu-toggle { display: block; }
  .site-nav {
    position: absolute;
    z-index: 10;
    top: 64px;
    right: 0;
    display: none;
    width: min(320px, calc(100vw - 28px));
    padding: 15px;
    border: 1px solid var(--line);
    border-radius: 13px;
    background: #fff;
    box-shadow: 0 16px 38px rgba(32, 57, 89, .14);
  }
  .site-header.is-open .site-nav { display: grid; gap: 2px; }
  .site-nav a { padding: 9px 10px; border-radius: 7px; }
  .site-nav a:hover { background: var(--soft); }
  main { padding-top: 18px; }
  .breadcrumb { margin-bottom: 18px; }
  .guide-hero { gap: 22px; padding: 24px 18px; border-radius: 14px; }
  h1 { max-width: none; font-size: 32px; line-height: 1.25; }
  .hero-intro { font-size: 14px; line-height: 1.72; }
  .chapter-nav { border-radius: 11px; }
  .guide-content { border-radius: 14px; }
  .guide-section { padding: 22px 18px; }
  .side-panel { grid-template-columns: 1fr; }
  .toc { grid-row: auto; }
  .related-grid { grid-template-columns: 1fr; }
  .related-grid a { min-height: 0; }
  .guide-directory-grid,
  .guide-principles { grid-template-columns: 1fr; }
  .guide-directory-card { min-height: 150px; }
  .data-table { display: block; overflow-x: auto; }
  .site-footer .footer-links { margin-left: 0; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; }
}