:root {
  --paper: #f7f5ef;
  --white: #ffffff;
  --ink: #172b3a;
  --muted: #607080;
  --line: #cfd7df;
  --line-dark: #8fa1b2;
  --blue: #255985;
  --blue-soft: #e7f0f7;
  --gold: #b97d00;
  --gold-soft: #f7eed8;
  --orange: #d97706;
  --grey: #8a96a3;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: "Microsoft YaHei", "PingFang SC", "Noto Sans SC", Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; }
img { max-width: 100%; }
button { font: inherit; }
:focus-visible { outline: 3px solid var(--gold); outline-offset: 3px; }
.report-shell { width: min(1220px, calc(100% - 48px)); margin-inline: auto; }
section[id] { scroll-margin-top: 98px; }
.skip-link { position: fixed; left: 16px; top: -80px; z-index: 100; padding: 11px 16px; color: #fff; background: var(--blue); }
.skip-link:focus { top: 12px; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 30;
  min-height: 70px;
  padding: 10px max(24px, calc((100% - 1220px) / 2));
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 28px;
  color: #edf3f6;
  background: rgba(23, 43, 58, .97);
  border-bottom: 1px solid rgba(255,255,255,.14);
  backdrop-filter: blur(14px);
}
.brand { display: inline-flex; align-items: center; gap: 11px; text-decoration: none; }
.brand-mark { width: 40px; height: 40px; display: grid; place-items: center; color: var(--ink); background: #d5a034; font-family: Georgia, serif; font-size: 18px; font-weight: 700; }
.brand > span:last-child { display: grid; gap: 2px; }
.brand strong { font-size: 15px; }
.brand small { color: #aebcc7; font-size: 10px; }
.site-nav { justify-self: center; display: flex; gap: 23px; }
.site-nav a { color: #c7d1d8; text-decoration: none; font-size: 12px; font-weight: 700; }
.site-nav a:hover, .site-nav a.is-active { color: #fff; }
.source-link { padding-bottom: 3px; color: #fff; text-decoration: none; border-bottom: 1px solid #738696; font-size: 12px; font-weight: 800; }

.hero { padding: 82px 0 76px; }
.hero-grid { display: grid; grid-template-columns: 1.02fr .98fr; gap: 54px; align-items: center; }
.kicker { margin: 0 0 16px; color: var(--gold); font-size: 12px; font-weight: 900; letter-spacing: .18em; }
.hero h1 { margin: 0; font-family: Georgia, "Songti SC", "SimSun", serif; font-size: clamp(47px, 5.5vw, 76px); line-height: 1.08; letter-spacing: -.045em; }
.hero-subtitle { margin: 24px 0 0; color: var(--blue); font-size: clamp(19px, 2.4vw, 31px); font-weight: 700; line-height: 1.45; }
.hero-conclusion { margin: 24px 0 0; padding: 18px 0 18px 18px; color: #263c4c; border-left: 4px solid var(--gold); font-size: 15px; line-height: 1.85; }
.hero-conclusion strong { color: var(--gold); }
.hero-sample { margin: 18px 0 0; color: #536575; font-size: 12px; font-weight: 700; line-height: 1.7; }
.hero-sample strong { color: var(--ink); }
.hero-lead { max-width: 940px; margin: 20px 0 0; color: #445665; font-size: 15px; line-height: 1.85; }
.hero-visual { margin: 0; padding-top: 12px; overflow: hidden; background: #fff; border-top: 3px solid var(--ink); }
.hero-visual img { width: 100%; display: block; cursor: zoom-in; }
.hero-visual figcaption { padding: 8px 2px 0; color: var(--muted); font-size: 10px; text-align: right; }
.headline-stats { margin: 44px 0 0; padding: 24px 0; display: grid; grid-template-columns: repeat(5, 1fr); border-top: 1px solid var(--line-dark); border-bottom: 1px solid var(--line-dark); }
.headline-stats div { padding: 0 26px; border-right: 1px solid var(--line); }
.headline-stats div:first-child { padding-left: 0; }
.headline-stats div:last-child { border-right: 0; }
.headline-stats dt { color: var(--muted); font-size: 12px; font-weight: 700; }
.headline-stats dd { margin: 5px 0 0; font-family: Georgia, serif; font-size: 47px; line-height: 1; }
.headline-stats small { margin-left: 5px; color: var(--muted); font-family: inherit; font-size: 13px; }
.hero-finding { max-width: 1030px; margin: 30px 0 0; padding-left: 20px; color: #344756; border-left: 4px solid var(--gold); font-size: 16px; line-height: 1.9; }
.hero-finding span { margin-right: 12px; color: var(--gold); font-weight: 900; }
.hero-actions { margin-top: 30px; display: flex; flex-wrap: wrap; gap: 12px; }
.button-primary, .button-secondary { min-height: 46px; padding: 0 20px; display: inline-flex; align-items: center; justify-content: center; text-decoration: none; font-size: 13px; font-weight: 800; }
.button-primary { color: #fff; background: var(--blue); }
.button-secondary { color: var(--ink); border: 1px solid var(--line-dark); }

.chapter { padding: 76px 0 54px; border-top: 1px solid var(--line-dark); }
.chapter-heading { margin-bottom: 30px; display: grid; grid-template-columns: 62px 1fr; gap: 24px; align-items: start; }
.chapter-heading > span { color: var(--gold); font-family: Georgia, serif; font-size: 38px; line-height: 1; }
.chapter-heading p { margin: 0 0 8px; color: var(--blue); font-size: 11px; font-weight: 900; letter-spacing: .14em; }
.chapter-heading h2 { max-width: 980px; margin: 0; font-family: Georgia, "Songti SC", "SimSun", serif; font-size: clamp(31px, 4vw, 50px); line-height: 1.28; letter-spacing: -.025em; }
.chapter-intro { max-width: 940px; margin: -4px 0 34px 86px; color: var(--muted); font-size: 15px; line-height: 1.9; }

.research-figure { margin: 0 0 48px; padding-top: 18px; background: var(--white); border-top: 3px solid var(--ink); }
.research-figure img { width: 100%; display: block; background: #fff; }
.research-figure .zoomable { cursor: zoom-in; }
.research-figure figcaption { padding: 14px 4px 0; color: var(--muted); font-size: 12px; line-height: 1.75; }
.research-figure figcaption b { color: var(--ink); }
.figure-pair { display: grid; grid-template-columns: 1fr 1fr; gap: 28px; align-items: start; }
.figure-pair .research-figure { margin-bottom: 44px; }

.method-line { margin: 32px 0 46px; padding: 0; list-style: none; display: grid; grid-template-columns: repeat(4, 1fr); border-top: 1px solid var(--line-dark); border-bottom: 1px solid var(--line-dark); }
.method-line li { position: relative; min-height: 130px; padding: 24px 24px 22px; border-right: 1px solid var(--line); }
.method-line li:last-child { border-right: 0; }
.method-line li:not(:last-child)::after { content: "→"; position: absolute; right: -12px; top: 49px; z-index: 2; width: 24px; height: 24px; display: grid; place-items: center; color: var(--gold); background: var(--paper); font-weight: 900; }
.method-line b { display: block; font-size: 16px; }
.method-line span { margin-top: 10px; display: block; color: var(--muted); font-size: 12px; line-height: 1.6; }
.prompt-layout { margin-bottom: 44px; display: grid; grid-template-columns: .72fr 1.28fr; gap: 42px; align-items: start; }
.prompt-layout h3 { margin: 0; font-size: 24px; }
.prompt-layout p { color: var(--muted); line-height: 1.9; }
.prompt-layout a { color: var(--blue); font-weight: 800; }
.prompt-layout pre { margin: 0; padding: 24px; overflow: auto; color: #e8eef2; background: var(--ink); font-family: Consolas, "SFMono-Regular", monospace; font-size: 12px; line-height: 1.75; }

.validation-statement { margin: 6px 0 32px; padding: 22px 0; color: #344756; border-top: 1px solid var(--line-dark); border-bottom: 1px solid var(--line-dark); font-size: 14px; line-height: 1.9; }
.boundary-list { margin: 0; padding: 0; list-style: none; display: grid; grid-template-columns: 1fr 1fr; column-gap: 38px; }
.boundary-list li { padding: 19px 0; display: grid; grid-template-columns: 145px 1fr; gap: 18px; border-top: 1px solid var(--line); }
.boundary-list b { color: var(--blue); font-size: 13px; }
.boundary-list span { color: var(--muted); font-size: 13px; line-height: 1.75; }
.download-line { margin: 38px 0 0; padding: 26px 0; display: flex; justify-content: space-between; align-items: center; gap: 24px; border-top: 3px solid var(--ink); }
.download-line p { max-width: 760px; margin: 0; color: var(--muted); line-height: 1.8; }

footer { margin-top: 48px; color: #b9c5cd; background: var(--ink); }
.footer-inner { min-height: 80px; display: flex; align-items: center; justify-content: space-between; gap: 24px; font-size: 11px; }

#figure-dialog { width: min(96vw, 1500px); max-width: none; padding: 42px 24px 22px; border: 0; background: #fff; box-shadow: 0 22px 70px rgba(0,0,0,.3); }
#figure-dialog::backdrop { background: rgba(9, 20, 30, .82); }
#figure-dialog img { width: 100%; max-height: 82vh; object-fit: contain; }
#figure-dialog p { margin: 12px 0 0; color: var(--muted); font-size: 12px; text-align: center; }
.dialog-close { position: absolute; right: 12px; top: 8px; width: 36px; height: 36px; border: 0; color: var(--ink); background: transparent; cursor: pointer; font-size: 30px; line-height: 1; }

@media (max-width: 1080px) {
  .site-header { grid-template-columns: 1fr auto; }
  .site-nav { display: none; }
  .hero-grid { grid-template-columns: 1fr; gap: 38px; }
  .hero-visual { max-width: 800px; }
  .figure-pair { grid-template-columns: 1fr; }
  .figure-pair .research-figure { margin-bottom: 32px; }
  .chapter-intro { margin-left: 0; }
}

@media (max-width: 760px) {
  .report-shell { width: min(100% - 28px, 1220px); }
  section[id] { scroll-margin-top: 78px; }
  .site-header { min-height: 64px; padding: 9px 14px; }
  .source-link { font-size: 11px; }
  .brand-mark { width: 36px; height: 36px; }
  .brand small { display: none; }
  .brand strong { font-size: 13px; }
  .hero { padding: 54px 0 52px; }
  .hero h1 { font-size: clamp(42px, 13vw, 62px); line-height: 1.12; }
  .hero-subtitle { margin-top: 18px; font-size: 19px; }
  .hero-lead { font-size: 14px; }
  .headline-stats { grid-template-columns: 1fr 1fr; padding: 0; }
  .headline-stats div { padding: 18px 12px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); }
  .headline-stats div:nth-child(2n) { border-right: 0; }
  .headline-stats div:last-child { grid-column: 1 / -1; border-right: 0; border-bottom: 0; text-align: center; }
  .headline-stats div:first-child { padding-left: 12px; }
  .headline-stats dd { font-size: 36px; }
  .hero-finding { font-size: 14px; }
  .hero-actions { display: grid; }
  .chapter { padding: 54px 0 38px; }
  .chapter-heading { grid-template-columns: 42px 1fr; gap: 12px; }
  .chapter-heading > span { font-size: 29px; }
  .chapter-heading h2 { font-size: 30px; }
  .research-figure { margin-bottom: 34px; padding-top: 12px; }
  .research-figure figcaption { font-size: 11px; }
  .method-line { grid-template-columns: 1fr; }
  .method-line li { min-height: auto; border-right: 0; border-bottom: 1px solid var(--line); }
  .method-line li:last-child { border-bottom: 0; }
  .method-line li:not(:last-child)::after { content: "↓"; left: 50%; right: auto; top: auto; bottom: -12px; transform: translateX(-50%); }
  .prompt-layout { grid-template-columns: 1fr; gap: 20px; }
  .prompt-layout pre { padding: 18px; font-size: 10px; }
  .boundary-list { grid-template-columns: 1fr; }
  .boundary-list li { grid-template-columns: 110px 1fr; }
  .download-line { align-items: flex-start; flex-direction: column; }
  .footer-inner { padding: 22px 0; align-items: flex-start; flex-direction: column; }
  #figure-dialog { padding: 42px 8px 16px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}