*, *::before, *::after { box-sizing: border-box; }

body, h1, h2, h3, h4, p, figure, blockquote, dl, dd, ol, ul, pre { margin: 0; }

ol[class], ul[class] { padding: 0; margin: 0; list-style: none; }

img { display: block; max-width: 100%; height: auto; }

button, input, select, textarea { font: inherit; color: inherit; }

a { color: #1B6FAE; }
a:hover { color: #0F4C81; }

:root {
  --page-max: 1240px;
  --gutter: 24px;
  --font-serif: "Noto Serif CJK SC", "Source Han Serif SC", "Songti SC", "SimSun", serif;
  --font-sans: "Noto Sans CJK SC", "Source Han Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", "Cascadia Code", "SF Mono", "Roboto Mono", Consolas, monospace;
  --color-gold: #D9A844;
  --color-gold-dark: #B98A30;
  --color-gold-bright: #FFE5B4;
  --color-rock: #6E6E76;
  --color-blue: #1B6FAE;
  --color-blue-dark: #0F4C81;
  --color-sand: #F5EFE0;
  --color-ink: #2B2B2E;
  --color-metal: #C9C9CE;
  --color-white: #FFFFFF;
  --color-dark: #1A1A1E;
  --color-blue-deep: #0A3A5E;
}

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.75;
  color: var(--color-ink);
  background-color: var(--color-sand);
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  font-family: var(--font-serif);
  font-weight: 900;
  line-height: 1.2;
  color: var(--color-ink);
}

::selection { background: var(--color-gold); color: var(--color-ink); }

:focus-visible {
  outline: 2px solid var(--color-blue);
  outline-offset: 2px;
}

#main-content { display: block; min-height: 60vh; }

.container {
  width: 100%;
  max-width: var(--page-max);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.container-narrow {
  width: 100%;
  max-width: 920px;
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.prose {
  max-width: 60ch;
  line-height: 1.75;
}

.section { padding-block: 48px; }

.grid { display: grid; gap: 24px; }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 20px;
  border: 1px solid var(--color-metal);
  background: transparent;
  color: var(--color-ink);
  font-family: var(--font-sans);
  font-size: 15px;
  font-weight: 600;
  line-height: 1.4;
  text-decoration: none;
  cursor: pointer;
  transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}
.btn:hover { color: var(--color-ink); border-color: var(--color-gold); }
.btn--primary { background: var(--color-gold); border-color: var(--color-gold); color: var(--color-ink); }
.btn--primary:hover { background: var(--color-gold-dark); border-color: var(--color-gold-dark); color: var(--color-ink); }
.btn--outline { border-color: var(--color-rock); color: var(--color-ink); }
.btn--outline:hover { border-color: var(--color-blue); color: var(--color-blue); }

.breadcrumb { font-family: var(--font-mono); font-size: 13px; }
.breadcrumb ol { display: flex; flex-wrap: wrap; gap: 4px 0; }
.breadcrumb li { display: inline-flex; align-items: center; }
.breadcrumb li + li::before { content: "/"; margin: 0 8px; color: var(--color-metal); }
.breadcrumb a { color: var(--color-rock); text-decoration: none; }
.breadcrumb a:hover { color: var(--color-blue); }
.breadcrumb [aria-current="page"] { color: var(--color-ink); font-weight: 600; }

.page-title {
  font-family: var(--font-serif);
  font-size: clamp(28px, 4vw, 38px);
  line-height: 1.2;
  color: var(--color-ink);
  margin-bottom: 12px;
}
.section-title {
  font-family: var(--font-serif);
  font-size: clamp(20px, 2.6vw, 28px);
  line-height: 1.2;
  color: var(--color-ink);
  margin-bottom: 12px;
}
.section-sub {
  color: var(--color-rock);
  max-width: 60ch;
  margin-bottom: 24px;
}

.exhibit { margin-block: 40px; }
.exhibit-label {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin-bottom: 14px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.12em;
  color: var(--color-rock);
  text-transform: uppercase;
}
.exhibit-label::before {
  content: "";
  flex: 0 0 auto;
  width: 32px;
  height: 2px;
  background: var(--color-gold);
  align-self: center;
}
.exhibit-num { color: var(--color-gold); font-weight: 700; }

.card {
  background: var(--color-white);
  border: 1px solid var(--color-metal);
  padding: 24px;
  transition: border-color 0.25s ease, transform 0.25s ease, box-shadow 0.25s ease;
}
.card:hover {
  border-color: var(--color-blue);
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(43, 43, 46, 0.06);
}

.stat-group {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 16px;
}
.stat { background: var(--color-white); border: 1px solid var(--color-metal); padding: 24px; }
.stat-value {
  display: block;
  font-family: var(--font-mono);
  font-size: 48px;
  font-weight: 700;
  line-height: 1;
  color: var(--color-blue);
}
.stat-label {
  display: block;
  margin-top: 8px;
  font-size: 14px;
  color: var(--color-rock);
}

.tag {
  display: inline-flex;
  align-items: center;
  padding: 3px 10px;
  background: var(--color-gold-bright);
  border: 1px solid var(--color-metal);
  color: var(--color-rock);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
}
.tag--blue { background: #E6F0F8; color: var(--color-blue); border-color: #BBD5E8; }

.table-wrap { overflow-x: auto; }
.table {
  width: 100%;
  border-collapse: collapse;
  background: var(--color-white);
  font-size: 14px;
}
.table th,
.table td {
  border: 1px solid var(--color-metal);
  padding: 10px 12px;
  text-align: left;
  vertical-align: top;
}
.table thead th {
  background: var(--color-sand);
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
}

.figure {
  position: relative;
  overflow: hidden;
  background-color: #E9E4D6;
  background-image:
    linear-gradient(45deg, rgba(110, 110, 118, 0.07) 25%, transparent 25%, transparent 75%, rgba(110, 110, 118, 0.07) 75%),
    linear-gradient(45deg, rgba(110, 110, 118, 0.07) 25%, transparent 25%, transparent 75%, rgba(110, 110, 118, 0.07) 75%);
  background-size: 20px 20px, 20px 20px;
  background-position: 0 0, 10px 10px;
  border: 1px solid var(--color-metal);
  min-height: 80px;
}
.figure--wide { aspect-ratio: 21 / 9; }
.figure--standard { aspect-ratio: 16 / 9; }
.figure--square { aspect-ratio: 1 / 1; }
.figure--tall { aspect-ratio: 4 / 5; }
.figure-img {
  position: absolute;
  inset: 0;
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

details { background: var(--color-white); border: 1px solid var(--color-metal); }
details + details { margin-top: 12px; }
summary {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  padding: 16px 20px;
  cursor: pointer;
  font-weight: 600;
  list-style: none;
}
summary::-webkit-details-marker { display: none; }
summary::after {
  content: "+";
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 18px;
  color: var(--color-blue);
}
details[open] summary::after { content: "−"; }
.faq-body { padding: 0 20px 18px; }

.toc {
  position: sticky;
  top: 24px;
  border-left: 1px solid var(--color-metal);
}
.toc-link {
  display: block;
  position: relative;
  padding: 8px 12px;
  color: var(--color-rock);
  font-size: 14px;
  text-decoration: none;
  line-height: 1.5;
  transition: color 0.2s ease;
}
.toc-link::before {
  content: "";
  position: absolute;
  left: -1px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: transparent;
}
.toc-link:hover { color: var(--color-blue); }
.toc-link.is-active { color: var(--color-ink); font-weight: 600; }
.toc-link.is-active::before { background: var(--color-gold); }
.toc-link[aria-current="true"] { color: var(--color-ink); font-weight: 600; }
.toc-link[aria-current="true"]::before { background: var(--color-gold); }

.skip-link {
  position: fixed;
  top: 8px;
  left: 8px;
  z-index: 3000;
  display: inline-block;
  padding: 10px 18px;
  background: var(--color-ink);
  color: var(--color-white) !important;
  font-family: var(--font-mono);
  font-size: 13px;
  text-decoration: none;
  transform: translateY(-160%);
  transition: transform 0.2s ease;
}
.skip-link:focus {
  transform: translateY(0);
  outline: 2px solid var(--color-gold-bright);
  outline-offset: 2px;
}

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0;
  height: 3px;
  background: var(--color-blue);
  z-index: 2000;
  pointer-events: none;
}

.site-header {
  position: relative;
  background: var(--color-white);
  border-top: 3px solid var(--color-gold);
  border-bottom: 1px solid var(--color-metal);
}

.header-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
  padding-block: 6px;
  padding-inline: max(var(--gutter), calc((100% - var(--page-max)) / 2));
  background: var(--color-sand);
  border-bottom: 1px solid var(--color-metal);
  font-size: 12px;
  color: var(--color-rock);
}

.header-meta-title {
  display: inline-flex;
  align-items: center;
  letter-spacing: 0.02em;
  white-space: nowrap;
}
.header-meta-title::before {
  content: "";
  display: inline-block;
  width: 6px;
  height: 6px;
  margin-right: 8px;
  background: var(--color-gold);
}

.header-meta-notes {
  font-family: var(--font-mono);
  letter-spacing: 0.08em;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.header-main {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding-block: 12px;
  padding-inline: max(var(--gutter), calc((100% - var(--page-max)) / 2));
}

.site-brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  flex-shrink: 0;
  color: var(--color-ink);
  text-decoration: none;
}
.site-brand:hover { color: var(--color-ink); }

.site-brand-mark {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  background: var(--color-gold);
  border: 1px solid var(--color-gold-dark);
  color: var(--color-ink);
  font-family: var(--font-serif);
  font-size: 20px;
  font-weight: 900;
}

.site-brand-text {
  display: flex;
  flex-direction: column;
  gap: 2px;
  line-height: 1.2;
}
.site-brand-name {
  font-family: var(--font-serif);
  font-size: 20px;
  font-weight: 900;
  color: var(--color-ink);
}
.site-brand-sub {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--color-rock);
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  margin-left: auto;
  padding: 8px 12px;
  background: transparent;
  border: 1px solid var(--color-metal);
  color: var(--color-ink);
  font-family: var(--font-sans);
  font-size: 14px;
  line-height: 1;
  cursor: pointer;
  transition: border-color 0.2s ease;
}
.nav-toggle:hover { border-color: var(--color-gold); }
.nav-toggle-bar {
  position: relative;
  display: block;
  width: 18px;
  height: 10px;
}
.nav-toggle-bar::before,
.nav-toggle-bar::after {
  content: "";
  position: absolute;
  left: 0;
  width: 18px;
  height: 2px;
  background: currentColor;
  transition: transform 0.25s ease;
}
.nav-toggle-bar::before { top: 0; }
.nav-toggle-bar::after { bottom: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle-bar::before { transform: translateY(4px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-bar::after { transform: translateY(-4px) rotate(-45deg); }
.nav-toggle-label { font-size: 13px; letter-spacing: 0.06em; }

.site-nav {
  display: flex;
  align-items: center;
  gap: 2px;
  margin-left: auto;
}

.nav-link {
  position: relative;
  display: block;
  padding: 8px 14px;
  font-size: 15px;
  font-weight: 500;
  color: var(--color-ink);
  text-decoration: none;
  transition: color 0.2s ease;
}
.nav-link:hover { color: var(--color-blue); }
.nav-link[aria-current="page"] { font-weight: 700; color: var(--color-ink); }
.nav-link[aria-current="page"]::after {
  content: "";
  position: absolute;
  left: 14px;
  right: 14px;
  bottom: 2px;
  height: 2px;
  background: var(--color-gold);
}

.site-footer {
  position: relative;
  margin-top: 72px;
  background: var(--color-blue-dark);
  color: rgba(255, 255, 255, 0.85);
  font-size: 14px;
}
.site-footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--color-gold);
}

.footer-primary {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(0, 0.8fr) minmax(0, 1fr);
  gap: 48px;
  padding-block: 52px 44px;
  padding-inline: max(var(--gutter), calc((100% - var(--page-max)) / 2));
}
.footer-primary > * { align-self: start; }
.footer-brand { min-width: 0; }
.footer-brand-link { display: inline-block; color: var(--color-white); text-decoration: none; }
.footer-brand-link:hover { color: var(--color-white); }
.footer-brand-name {
  display: block;
  font-family: var(--font-serif);
  font-size: 24px;
  font-weight: 900;
  color: var(--color-white);
  line-height: 1.2;
}
.footer-brand-desc {
  display: block;
  margin-top: 4px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: rgba(255, 255, 255, 0.65);
}
.footer-trust {
  margin-top: 16px;
  max-width: 52ch;
  padding-left: 14px;
  border-left: 2px solid var(--color-gold);
  font-size: 13px;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.78);
}

.footer-col { min-width: 0; }
.footer-heading {
  margin-bottom: 14px;
  padding-bottom: 10px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.22);
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-gold);
}
.footer-links { display: grid; gap: 9px; }
.footer-links a { color: rgba(255, 255, 255, 0.85); text-decoration: none; transition: color 0.2s ease; }
.footer-links a:hover { color: var(--color-gold-bright); }

.footer-contact {
  margin-top: 16px;
  font-family: var(--font-mono);
  font-size: 13px;
  color: rgba(255, 255, 255, 0.85);
  overflow-wrap: anywhere;
}
.footer-address {
  margin-top: 6px;
  font-size: 13px;
  color: rgba(255, 255, 255, 0.6);
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 8px 24px;
  padding-block: 14px;
  padding-inline: max(var(--gutter), calc((100% - var(--page-max)) / 2));
  border-top: 1px solid rgba(255, 255, 255, 0.16);
  background: var(--color-blue-deep);
  font-family: var(--font-mono);
  font-size: 12px;
  color: rgba(255, 255, 255, 0.72);
}

.back-to-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  z-index: 1500;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 16px;
  background: var(--color-ink);
  border: 1px solid var(--color-gold);
  color: var(--color-gold-bright);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  line-height: 1;
  cursor: pointer;
  transform: translateY(8px);
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.25s ease, transform 0.25s ease, visibility 0.25s ease, background-color 0.2s ease, border-color 0.2s ease;
}
.back-to-top::before { content: "↑"; font-size: 16px; line-height: 1; }
.back-to-top.is-visible { opacity: 1; visibility: visible; transform: translateY(0); }
.back-to-top:hover { background: var(--color-blue-dark); border-color: var(--color-blue); color: var(--color-white); }

[data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.45s ease, transform 0.45s ease;
}
[data-reveal][data-revealed] { opacity: 1; transform: translateY(0); }

@media (max-width: 880px) {
  .nav-toggle { display: inline-flex; }

  .site-nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    margin: 0;
    padding: 4px max(var(--gutter), calc((100% - var(--page-max)) / 2)) 16px;
    background: var(--color-white);
    border-top: 1px solid var(--color-gold);
    border-bottom: 1px solid var(--color-metal);
    box-shadow: 0 16px 24px rgba(43, 43, 46, 0.08);
  }
  .site-nav[data-open] { display: flex; }

  .nav-link {
    padding: 13px 0;
    border-bottom: 1px solid #EDECE6;
    font-size: 16px;
  }
  .nav-link:last-child { border-bottom: 0; }
  .nav-link[aria-current="page"]::after { display: none; }
  .nav-link[aria-current="page"] { border-bottom-color: var(--color-gold); }

  .grid--3, .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-primary { grid-template-columns: 1fr; gap: 36px; padding-block: 40px 36px; }
  .footer-bottom { flex-direction: column; align-items: flex-start; gap: 6px; }
}

@media (max-width: 640px) {
  :root { --gutter: 16px; }

  .header-meta { justify-content: center; }
  .header-meta-notes { display: none; }
  .header-main { gap: 12px; padding-block: 10px; }
  .site-brand-mark { width: 32px; height: 32px; font-size: 17px; }
  .site-brand-name { font-size: 17px; }
  .site-brand-sub { font-size: 9px; }
  .back-to-top { right: 16px; bottom: 16px; padding: 8px 12px; }
  .footer-primary { gap: 32px; }
  .grid--2, .grid--3, .grid--4 { grid-template-columns: 1fr; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
  [data-reveal] { opacity: 1; transform: none; }
}