:root {
  --paper: #fbfcfb;
  --paper-deep: #e8f0f0;
  --wash: #e7f2f2;
  --ink: #24383d;
  --muted: #647579;
  --faint: #8b9c9f;
  --line: rgba(36, 56, 61, .16);
  --primary: #0a7182;
  --primary-soft: #e2f0f1;
  --green: #4c8c81;
  --earth: #b58a62;
  --red: #c06a62;
  --shadow: 0 18px 48px rgba(66, 57, 44, .10);
  --serif: "Iowan Old Style", Baskerville, "Songti SC", "STSong", "Noto Serif CJK SC", Georgia, serif;
  --sans: "Avenir Next", -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", "Segoe UI", sans-serif;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--ink); background: var(--paper); font-family: var(--sans); line-height: 1.65; }
a { color: inherit; }
button { font: inherit; }
.topbar { position: sticky; top: 0; z-index: 20; display: flex; align-items: center; justify-content: space-between; gap: 22px; padding: 17px clamp(20px, 5vw, 78px); background: rgba(251,252,251,.90); border-bottom: 1px solid var(--line); backdrop-filter: blur(14px); }
.brand { display: flex; align-items: baseline; gap: 12px; min-width: 0; }
.brand-name { font-family: var(--serif); font-size: 23px; letter-spacing: .01em; white-space: nowrap; }
.brand-sub { color: var(--muted); font-size: 11px; letter-spacing: .11em; white-space: nowrap; }
.top-actions { display: flex; align-items: center; gap: 16px; }
.nav-links { display: flex; gap: 18px; color: var(--muted); font-size: 12px; }
.nav-links a { text-decoration: none; }
.nav-links a:hover { color: var(--primary); }
.lang-btn { border: 1px solid var(--line); border-radius: 999px; padding: 7px 12px; color: var(--ink); background: rgba(255,255,255,.35); cursor: pointer; font-size: 12px; }
.lang-btn:hover { border-color: var(--primary); color: var(--primary); }
.page { width: min(1260px, calc(100% - 40px)); margin: 0 auto; }
.hero { position: relative; overflow: hidden; display: grid; grid-template-columns: minmax(0, 1.35fr) minmax(280px, .65fr); gap: 28px; min-height: 450px; padding: clamp(42px, 7vw, 90px) clamp(24px, 6vw, 82px); background: linear-gradient(135deg, rgba(255,255,255,.58), rgba(232,240,240,.78)); border-bottom: 1px solid var(--line); }
.hero::before { content: ""; position: absolute; inset: 0; pointer-events: none; opacity: .45; background-image: radial-gradient(circle at 9% 28%, rgba(154,106,62,.13) 0 1px, transparent 2px), radial-gradient(circle at 86% 64%, rgba(49,95,136,.13) 0 1px, transparent 2px); background-size: 24px 24px, 34px 34px; mask-image: linear-gradient(120deg, #000, transparent 68%); }
.hero-copy, .hero-metrics { position: relative; z-index: 1; }
.kicker { margin: 0 0 18px; color: var(--primary); font-size: 11px; font-weight: 700; letter-spacing: .22em; text-transform: uppercase; }
h1 { max-width: 820px; margin: 0; font-family: var(--serif); font-size: clamp(40px, 6vw, 75px); font-weight: 500; line-height: 1.08; letter-spacing: -.035em; }
.hero-lead { max-width: 690px; margin: 25px 0 0; color: var(--muted); font-family: var(--serif); font-size: clamp(17px, 2vw, 22px); line-height: 1.55; }
.hero-meta { display: flex; flex-wrap: wrap; gap: 8px 20px; margin-top: 28px; color: var(--faint); font-family: var(--mono); font-size: 10px; letter-spacing: .03em; }
.hero-metrics { align-self: end; display: grid; grid-template-columns: 1fr 1fr; border-top: 2px solid var(--ink); border-bottom: 1px solid var(--line); }
.metric { min-height: 116px; padding: 18px 14px 15px 0; }
.metric:nth-child(even) { padding-left: 17px; border-left: 1px solid var(--line); }
.metric:nth-child(n+3) { border-top: 1px solid var(--line); }
.metric-label { display: block; color: var(--muted); font-size: 11px; }
.metric-value { display: block; margin-top: 17px; color: var(--primary); font-family: var(--serif); font-size: 34px; line-height: 1; }
.metric-note { display: block; margin-top: 6px; color: var(--faint); font-size: 10px; }
.toc { display: grid; grid-template-columns: repeat(5, 1fr); margin-top: 28px; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.toc a { display: block; padding: 16px 14px 16px 0; text-decoration: none; color: var(--muted); font-size: 12px; }
.toc a + a { padding-left: 14px; border-left: 1px solid var(--line); }
.toc a:hover { color: var(--primary); background: rgba(255,255,255,.28); }
.toc b { display: block; margin-bottom: 4px; color: var(--primary); font-family: var(--mono); font-size: 10px; }
.section { padding: 74px 0 80px; border-bottom: 1px solid var(--line); scroll-margin-top: 88px; }
.section-head { display: grid; grid-template-columns: 44px minmax(0, 1fr); gap: 16px; max-width: 900px; margin-bottom: 28px; }
.section-no { padding-top: 8px; color: var(--primary); font-family: var(--mono); font-size: 11px; }
h2 { margin: 0; font-family: var(--serif); font-size: clamp(29px, 4vw, 44px); font-weight: 500; line-height: 1.18; letter-spacing: -.025em; }
.section-lead { max-width: 790px; margin: 10px 0 0; color: var(--muted); font-size: 14px; line-height: 1.85; }
.grid-2 { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 18px; }
.panel { min-width: 0; padding: 23px; background: rgba(255,255,255,.46); border: 1px solid var(--line); border-top: 2px solid var(--ink); }
.panel h3 { margin: 0 0 7px; font-family: var(--serif); font-size: 21px; font-weight: 500; }
.panel p { margin: 0; color: var(--muted); font-size: 13px; line-height: 1.8; }
.panel-note { margin-top: 17px !important; padding-top: 13px; border-top: 1px solid var(--line); color: var(--faint) !important; font-size: 11px !important; }
.audit-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); border-top: 2px solid var(--ink); border-bottom: 1px solid var(--line); }
.audit-card { min-height: 130px; padding: 20px 20px 18px 0; }
.audit-card + .audit-card { padding-left: 20px; border-left: 1px solid var(--line); }
.audit-card label { display: block; color: var(--muted); font-size: 11px; }
.audit-card strong { display: block; margin-top: 17px; color: var(--ink); font-family: var(--serif); font-size: 31px; font-weight: 500; line-height: 1; }
.audit-card small { display: block; margin-top: 8px; color: var(--faint); font-size: 11px; }
.note { margin-top: 18px; padding: 15px 18px; background: rgba(232,240,240,.72); border-left: 3px solid var(--earth); color: var(--muted); font-size: 12px; line-height: 1.8; }
.chart { width: 100%; height: 340px; }
.chart-tall { height: 390px; }
.chart-panel { padding-bottom: 12px; }
.chart-caption { margin: 10px 0 0; color: var(--faint); font-size: 11px; line-height: 1.7; }
.table-wrap { overflow-x: auto; border-top: 2px solid var(--ink); border-bottom: 1px solid var(--line); }
table { width: 100%; min-width: 700px; border-collapse: collapse; }
th { padding: 12px 13px; border-bottom: 1px solid var(--line); color: var(--muted); font-size: 11px; font-weight: 650; text-align: right; white-space: nowrap; }
th:first-child, td:first-child { text-align: left; }
td { padding: 14px 13px; border-bottom: 1px solid rgba(36,56,61,.10); color: var(--ink); font-size: 12px; text-align: right; font-variant-numeric: tabular-nums; }
tbody tr:last-child td { border-bottom: 0; }
tbody tr.primary { background: var(--primary-soft); }
tbody tr.primary td:first-child { box-shadow: inset 3px 0 var(--primary); }
.badge { display: inline-block; padding: 3px 7px; border-radius: 999px; background: var(--primary-soft); color: var(--primary); font-family: var(--mono); font-size: 10px; }
.method-list { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); border-top: 2px solid var(--ink); border-bottom: 1px solid var(--line); }
.method { min-height: 190px; padding: 20px 20px 20px 0; }
.method + .method { padding-left: 20px; border-left: 1px solid var(--line); }
.method-no { color: var(--primary); font-family: var(--mono); font-size: 11px; }
.method h3 { margin: 29px 0 8px; font-family: var(--serif); font-size: 18px; font-weight: 500; }
.method p { margin: 0; color: var(--muted); font-size: 12px; line-height: 1.75; }
.limit-list { display: grid; gap: 12px; margin: 0; padding: 0; list-style: none; }
.limit-list li { display: grid; grid-template-columns: 18px 1fr; gap: 10px; color: var(--muted); font-size: 13px; line-height: 1.75; }
.limit-list li::before { content: '—'; color: var(--primary); }
.book-intro { padding: 64px 0 70px; border-bottom: 1px solid var(--line); scroll-margin-top: 88px; }
.book-heading { display: grid; grid-template-columns: 44px minmax(0, 1fr) auto; gap: 16px; align-items: end; }
.book-heading .kicker { color: #0a7182; }
.book-lead { max-width: 760px; margin: 10px 0 0; color: var(--muted); font-family: var(--serif); font-size: 16px; line-height: 1.75; }
.book-hint { color: #0a7182; font-family: var(--mono); font-size: 10px; letter-spacing: .03em; white-space: nowrap; }
.book-viewport { display: flex; gap: 20px; margin: 28px -6px 0; padding: 10px 6px 20px; overflow-x: auto; scroll-snap-type: x mandatory; scrollbar-color: #0a7182 var(--paper-deep); scrollbar-width: thin; }
.book-spread { flex: 0 0 min(100%, 1080px); display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); min-height: 450px; scroll-snap-align: start; filter: drop-shadow(0 18px 25px rgba(36, 74, 80, .14)); }
.book-page { position: relative; min-width: 0; overflow: hidden; padding: clamp(28px, 4vw, 54px); background: #ffffff; border: 1px solid rgba(10, 113, 130, .24); color: #2f464b; }
.book-page::before { content: ''; position: absolute; inset: 0; pointer-events: none; opacity: .32; background: radial-gradient(circle at 20% 15%, rgba(181,138,98,.13), transparent 28%), linear-gradient(108deg, transparent 0 72%, rgba(10,113,130,.06)); }
.book-page > * { position: relative; z-index: 1; }
.book-page:first-child { border-right: 0; border-radius: 6px 0 0 6px; }
.book-page + .book-page { border-left: 1px solid rgba(10, 113, 130, .18); border-radius: 0 6px 6px 0; }
.book-cover { display: flex; flex-direction: column; justify-content: center; background: linear-gradient(145deg, #064b5a, #0a7182 56%, #8cb8b0); color: #f5fbfb; }
.book-cover::before { opacity: .2; background: radial-gradient(circle at 83% 16%, #d5eceb 0 2px, transparent 3px), radial-gradient(circle at 15% 72%, #d5eceb 0 1px, transparent 2px); background-size: 24px 24px, 17px 17px; }
.book-ribbon { position: absolute; top: 28px; right: 30px; padding: 5px 9px; border: 1px solid rgba(245,251,251,.5); color: #f5fbfb; font-family: var(--mono); font-size: 9px; letter-spacing: .08em; }
.book-series, .book-page-label { color: #b58a62; font-family: var(--mono); font-size: 10px; letter-spacing: .16em; text-transform: uppercase; }
.book-cover .book-series { color: rgba(245,251,251,.72); }
.book-page h3 { max-width: 430px; margin: 20px 0 18px; font-family: var(--serif); font-size: clamp(26px, 3.2vw, 43px); font-weight: 500; line-height: 1.18; }
.book-page:not(.book-cover) h3 { font-size: clamp(24px, 2.7vw, 36px); color: #235661; }
.book-page p { max-width: 470px; color: #667a7d; font-size: 13px; line-height: 1.9; }
.book-cover-note { margin-top: auto; color: rgba(245,251,251,.78) !important; font-family: var(--serif); font-size: 15px !important; }
.book-facts { display: grid; grid-template-columns: auto 1fr; gap: 6px 15px; max-width: 280px; margin-top: 34px; padding-top: 18px; border-top: 1px solid rgba(10,113,130,.2); color: #667a7d; font-size: 11px; }
.book-facts b { color: #0a7182; font-family: var(--serif); font-size: 29px; font-weight: 500; line-height: 1; }
.book-result { display: grid; grid-template-columns: 108px 1fr; gap: 12px; align-items: baseline; margin-top: 24px; padding-bottom: 12px; border-bottom: 1px solid rgba(10,113,130,.18); }
.book-result b { color: #0a7182; font-family: var(--serif); font-size: 43px; font-weight: 500; line-height: 1; }
.book-result span { color: #667a7d; font-size: 12px; }
.book-footnote { margin-top: 24px !important; color: #7a8f93 !important; font-size: 11px !important; }
.book-stamp { display: inline-block; margin-top: 34px; padding: 8px 13px; border: 1px solid #0a7182; color: #0a7182; font-family: var(--mono); font-size: 10px; letter-spacing: .1em; transform: rotate(-3deg); }
.book-list { display: grid; gap: 14px; margin: 28px 0 0; padding: 0; list-style: none; color: #667a7d; font-size: 13px; }
.book-list li { display: grid; grid-template-columns: 14px 1fr; gap: 8px; }
.book-list li::before { content: '•'; color: #0a7182; }
.book-continue { display: inline-block; margin-top: 30px; color: #0a7182; font-family: var(--serif); font-size: 16px; text-decoration: none; }
.book-continue:hover { text-decoration: underline; }
.book-page-number { position: absolute; right: 30px; bottom: 23px; color: #8ca4a7; font-family: var(--mono); font-size: 10px; }
.book-cover .book-page-number { color: rgba(245,251,251,.7); }
.book-index { display: flex; flex-wrap: wrap; gap: 0; margin-top: 18px; border-top: 1px solid rgba(10,113,130,.24); border-bottom: 1px solid rgba(10,113,130,.24); }
.book-index a { display: flex; gap: 9px; align-items: baseline; padding: 12px 18px 12px 0; color: #0a7182; font-size: 12px; text-decoration: none; }
.book-index a + a { margin-left: 18px; padding-left: 18px; border-left: 1px solid rgba(10,113,130,.2); }
.book-index b { font-family: var(--mono); font-size: 10px; }
.cv-note { margin-top: 15px; padding: 13px 17px; background: rgba(232,240,240,.55); border-left: 3px solid #0a7182; color: var(--muted); font-size: 12px; line-height: 1.8; }
.shap-panel { background: rgba(255,255,255,.34); }
.shap-chart { min-height: 430px; }
.footer { display: flex; justify-content: space-between; gap: 20px; padding: 28px 0 52px; color: var(--faint); font-size: 11px; }
.footer a { color: var(--primary); text-decoration: none; }
.footer-links { display: flex; gap: 18px; }
[data-lang] { display: none; }
body.lang-zh [data-lang="zh"], body.lang-en [data-lang="en"] { display: initial; }
@media (max-width: 900px) {
  .hero { grid-template-columns: 1fr; min-height: 0; }
  .hero-metrics { max-width: 620px; }
  .toc { grid-template-columns: repeat(3, 1fr); }
  .toc a:nth-child(4) { border-left: 0; padding-left: 0; }
  .grid-3, .method-list { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .book-heading { grid-template-columns: 29px minmax(0, 1fr); }
  .book-hint { grid-column: 2; }
  .method:nth-child(3) { border-left: 0; padding-left: 0; border-top: 1px solid var(--line); }
  .method:nth-child(4) { border-top: 1px solid var(--line); }
}
@media (max-width: 620px) {
  .topbar { align-items: flex-start; padding: 14px 18px; }
  .brand { display: block; }
  .brand-sub { display: block; margin-top: 2px; font-size: 9px; }
  .nav-links { display: none; }
  .page { width: min(100% - 28px, 1260px); }
  .hero { margin-inline: -14px; padding: 50px 24px 38px; }
  h1 { font-size: 43px; }
  .toc, .grid-2, .grid-3, .method-list, .audit-grid { grid-template-columns: 1fr; }
  .toc a + a, .audit-card + .audit-card, .method + .method { padding-left: 0; border-left: 0; border-top: 1px solid var(--line); }
  .section { padding: 52px 0 58px; }
  .section-head { grid-template-columns: 29px 1fr; }
  .chart, .chart-tall { height: 300px; }
  .book-intro { padding: 52px 0 58px; }
  .book-heading { align-items: start; }
  .book-viewport { margin-top: 22px; }
  .book-spread { flex-basis: 88vw; grid-template-columns: 1fr; min-height: 0; }
  .book-page { min-height: 360px; padding: 31px 27px; }
  .book-page:first-child { border-right: 1px solid rgba(10,113,130,.24); border-bottom: 0; border-radius: 6px 6px 0 0; }
  .book-page + .book-page { border-left: 1px solid rgba(10,113,130,.24); border-top: 0; border-radius: 0 0 6px 6px; }
  .book-page h3, .book-page:not(.book-cover) h3 { font-size: 29px; }
  .book-index { overflow-x: auto; flex-wrap: nowrap; }
  .book-index a { white-space: nowrap; }
  .footer { display: block; }
  .footer-links { margin-top: 10px; }
}

/* Study report: plum, pale grey and muted sage. */
.book-heading { align-items: start; grid-template-columns: 44px minmax(0, 1fr); }
.book-controls { display:flex; justify-content:flex-end; gap:8px; margin-top:18px; }
.book-controls button { width:40px; height:36px; border:1px solid var(--line); color:var(--primary); background:transparent; cursor:pointer; border-radius:3px; }
.book-controls button:hover { background:var(--primary-soft); }
.book-controls button:disabled { opacity:.3; cursor:default; }
.book-viewport { margin-top:8px; }
.metric-value,.book-result b,.book-facts b,.audit-card strong { font-family:var(--serif); font-variant-numeric:lining-nums tabular-nums; }
.book-list li { display:block; padding-left:18px; position:relative; }
.book-list li::before { position:absolute; left:0; }
.book-cover::before {
  background:
    linear-gradient(90deg, rgba(0,0,0,.16), transparent 10%, transparent 96%, rgba(0,0,0,.12)),
    radial-gradient(circle, rgba(213,236,235,.44) 0 1.7px, transparent 2px),
    radial-gradient(circle, rgba(247,223,180,.24) 0 1px, transparent 1.7px);
  background-size: auto, 24px 24px, 17px 17px;
  background-position: 0 0, 2px 3px, 8px 11px;
  opacity: 1;
}
@media(prefers-reduced-motion:reduce) { html { scroll-behavior:auto; } }

/* Match navigation labels and section numbers throughout the report. */
.topbar { flex-wrap:wrap; gap:10px 22px; }
.top-actions { flex:1; justify-content:flex-end; }
.nav-links { gap:14px; }
.nav-links a { white-space:nowrap; padding:7px 0; border-bottom:2px solid transparent; }
.nav-links b { font-family:var(--mono); font-size:10px; }
.nav-links a[aria-current="location"] { color:var(--primary); border-bottom-color:var(--primary); }
.toc { grid-template-columns:repeat(6,minmax(0,1fr)); }
.toc a[aria-current="location"], .book-index a[aria-current="location"] { background:var(--primary-soft); color:var(--primary); }
.analysis-explanation { margin-top:28px; display:grid; gap:24px; max-width:940px; }
.analysis-explanation article { padding-top:20px; border-top:1px solid var(--line); }
.analysis-explanation h3 { margin:0 0 10px; font-family:var(--serif); font-size:23px; font-weight:500; }
.analysis-explanation p { margin:0; color:var(--muted); font-size:15px; line-height:1.95; }
.book-detail { display:inline-block; margin:16px 0 22px; color:var(--primary); font-size:12px; text-underline-offset:4px; }
.book-cover .book-detail { color:#f5fbfb; }
html { scroll-padding-top:var(--nav-offset,110px); }
.section, .book-intro { scroll-margin-top:0; }
@media(max-width:1100px) {
  .top-actions { flex-basis:100%; }
  .nav-links { flex:1; overflow-x:auto; }
  .toc { grid-template-columns:repeat(3,minmax(0,1fr)); }
}
@media(max-width:620px) {
  .nav-links { display:flex; gap:16px; }
  .topbar { padding:10px 14px; }
  .top-actions { min-width:0; gap:10px; }
  .toc { grid-template-columns:repeat(2,minmax(0,1fr)); }
  .analysis-explanation p { font-size:14px; }
}

.analysis-method { margin: 8px 0 28px; }
.analysis-method article { border-top: 0; padding-top: 0; }