:root {
  --color-surface: #f3f2f1;
  --color-surface-alt: #ebe9e8;
  --color-surface-deep: #dfdddb;
  --color-ink: #4a423b;
  --color-ink-soft: #73685e;
  --color-ink-muted: #8c7f73;
  --color-line: #d5d2d0;
  --color-primary: #a16936;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #e8dfd7;
  --color-accent: #be561e;
  --color-accent-ink: #ffffff;
  --color-highlight: #e9d6cb;
  --color-focus: #b64b11;
  --color-contrast-surface: #221b15;
  --color-contrast-ink: #e7e5e4;
  --color-contrast-line: #4d4743;
  --color-contrast-accent: #dd6422;
  --overlay-scrim: linear-gradient(180deg, rgba(34, 27, 21, 0.35) 0%, rgba(34, 27, 21, 0.72) 55%, rgba(34, 27, 21, 0.92) 100%);
  --font-heading: STZhongsong, "Source Han Serif SC", "Songti SC", SimSun, serif;
  --font-body: "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: ui-monospace, Menlo, Consolas, monospace;
  --text-xs: 11.0px;
  --text-sm: 14.7px;
  --text-base: 17px;
  --text-lg: 22.7px;
  --text-xl: 30.2px;
  --text-2xl: 40.3px;
  --text-3xl: 53.7px;
  --text-4xl: 71.5px;
  --text-display: clamp(43px, 8.8vw, 113px);
  --text-figure: clamp(36px, 6.3vw, 81px);
  --weight-heading: 678;
  --weight-body: 400;
  --leading-body: 1.77;
  --leading-heading: 1.27;
  --tracking-heading: 0.028em;
  --radius-sm: 1px;
  --radius-md: 2px;
  --radius-lg: 2px;
  --radius-pill: 2px;
  --border-thin: 1px;
  --border-thick: 2px;
  --shadow-1: 0 1px 0 rgba(74, 66, 59, 0.12);
  --shadow-2: 0 2px 0 rgba(74, 66, 59, 0.18);
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --container: 1080px;
  --measure: 74ch;
  --gutter: 24px;
  --section-y: 93px;
  --section-y-lg: 130px;
}

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background-color: var(--color-surface);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: var(--weight-body);
  line-height: var(--leading-body);
  letter-spacing: 0.012em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4, h5, h6 {
  margin: 0;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

p { margin: 0; }

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

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

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
}

a {
  color: var(--color-primary);
  text-decoration-thickness: var(--border-thin);
  text-underline-offset: 3px;
}

a:hover { color: var(--color-accent); }

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

[hidden] { display: none !important; }

p, li, dd { text-wrap: pretty; }

/* ===== layout ===== */
.container {
  width: min(100% - calc(var(--space-3) * 2), var(--container));
  margin-inline: auto;
}

.section { padding-block: var(--section-y); }
.section--lg { padding-block: var(--section-y-lg); }
.section--tight { padding-block: var(--space-6); }
.section--alt { background-color: var(--color-surface-alt); }
.section--deep { background-color: var(--color-surface-deep); }

.section--contrast {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}
.section--contrast h1,
.section--contrast h2,
.section--contrast h3,
.section--contrast h4 { color: var(--color-contrast-ink); }
.section--contrast a { color: var(--color-contrast-accent); }

.grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gutter);
}

.span-3 { grid-column: span 3; }
.span-4 { grid-column: span 4; }
.span-6 { grid-column: span 6; }
.span-8 { grid-column: span 8; }
.span-12 { grid-column: span 12; }

.prose { max-width: var(--measure); }

/* ===== typography blocks ===== */
.section-head {
  display: grid;
  gap: var(--space-2);
  margin-bottom: var(--space-6);
}

.section-head--center {
  justify-items: center;
  text-align: center;
}

.eyebrow {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.3em;
  text-transform: uppercase;
  color: var(--color-primary);
}

.section-title { font-size: var(--text-2xl); }

.section-lede {
  max-width: var(--measure);
  font-size: var(--text-lg);
  color: var(--color-ink-soft);
}

.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.08em;
}

.term {
  font-style: normal;
  background-color: var(--color-highlight);
  border-bottom: var(--border-thin) solid var(--color-accent);
  border-radius: var(--radius-sm);
  padding: 0 4px;
}

.callout {
  background-color: var(--color-highlight);
  border-left: calc(var(--border-thick) * 2) solid var(--color-accent);
  border-radius: var(--radius-sm);
  padding: var(--space-3) var(--space-4);
  color: var(--color-ink);
}

/* ===== breadcrumb ===== */
.breadcrumb { padding-top: var(--space-3); }

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.14em;
  color: var(--color-ink-muted);
}

.breadcrumb__list li::after {
  content: "/";
  margin-left: var(--space-2);
  color: var(--color-line);
}

.breadcrumb__list li:last-child::after { content: none; }

.breadcrumb__list a {
  color: var(--color-ink-soft);
  text-decoration: none;
}

.breadcrumb__list a:hover { color: var(--color-accent); }

/* ===== buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-1);
  font-family: var(--font-body);
  font-size: var(--text-sm);
  letter-spacing: 0.1em;
  line-height: 1;
  padding: 11px var(--space-3);
  border: var(--border-thin) solid transparent;
  border-radius: var(--radius-sm);
  text-decoration: none;
  cursor: pointer;
  transition: color 140ms ease, background-color 140ms ease, border-color 140ms ease;
}

.btn--solid {
  background-color: var(--color-primary);
  border-color: var(--color-primary);
  color: var(--color-primary-ink);
}
.btn--solid:hover {
  background-color: var(--color-accent);
  border-color: var(--color-accent);
  color: var(--color-accent-ink);
}

.btn--line {
  border-color: var(--color-ink-soft);
  color: var(--color-ink);
  background-color: transparent;
}
.btn--line:hover {
  border-color: var(--color-accent);
  background-color: var(--color-primary-soft);
  color: var(--color-accent);
}

.btn--onDark {
  border-color: var(--color-contrast-line);
  color: var(--color-contrast-ink);
}
.btn--onDark:hover {
  border-color: var(--color-contrast-accent);
  color: var(--color-contrast-accent);
}

.btn--small {
  padding: 7px var(--space-2);
  font-size: var(--text-xs);
  letter-spacing: 0.12em;
}

.copy-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  padding: 5px 9px;
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  background-color: var(--color-surface);
  color: var(--color-ink-soft);
  cursor: pointer;
  transition: color 140ms ease, border-color 140ms ease;
}
.copy-btn:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}
.copy-btn[data-copied] {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

/* ===== tags ===== */
.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.12em;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  background-color: var(--color-primary-soft);
  color: var(--color-primary);
}

.tag--accent {
  background-color: var(--color-highlight);
  color: var(--color-accent);
}

/* ===== ticket (双线票券框) ===== */
.ticket {
  position: relative;
  background-color: var(--color-surface);
  border: var(--border-thin) solid var(--color-ink-soft);
  border-radius: var(--radius-sm);
  padding: var(--space-4);
}

.ticket::after {
  content: "";
  position: absolute;
  inset: 3px;
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  pointer-events: none;
}

.ticket > * { position: relative; z-index: 1; }

.ticket__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-2);
  padding-bottom: var(--space-2);
  margin-bottom: var(--space-3);
  border-bottom: var(--border-thin) solid var(--color-line);
}

.ticket__body { display: grid; gap: var(--space-2); }

/* ===== data list ===== */
.data-list { border-top: var(--border-thin) solid var(--color-line); }

.data-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: baseline;
  gap: var(--space-3);
  padding-block: var(--space-2);
  border-bottom: var(--border-thin) solid var(--color-line);
}

.data-row__label { color: var(--color-ink-soft); }

.data-row__value {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.06em;
  color: var(--color-ink);
  text-align: right;
}

.data-row__value--accent { color: var(--color-accent); }

/* ===== index list ===== */
.index-list {
  display: grid;
  border-top: var(--border-thin) solid var(--color-line);
}

.index-list li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: baseline;
  gap: var(--space-3);
  padding-block: var(--space-2);
  border-bottom: var(--border-thin) solid var(--color-line);
}

.index-list__no {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.14em;
  color: var(--color-accent);
}

/* ===== media ===== */
.media-frame {
  position: relative;
  overflow: hidden;
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
  background-color: var(--color-surface-deep);
}

.media-frame > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: inherit;
}

.media-frame--wide { aspect-ratio: 16 / 9; }
.media-frame--tall { aspect-ratio: 4 / 5; }
.media-frame--square { aspect-ratio: 1 / 1; }

.media-frame--print > img {
  filter: grayscale(0.3) contrast(1.06) sepia(0.1);
}

.media-frame__scrim {
  position: absolute;
  inset: 0;
  background: var(--overlay-scrim);
  z-index: 1;
}

.media-frame__caption {
  position: absolute;
  inset-inline: 0;
  bottom: 0;
  z-index: 2;
  padding: var(--space-3);
  color: var(--color-contrast-ink);
  font-size: var(--text-sm);
  letter-spacing: 0.04em;
}

/* ===== filter chips ===== */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-1);
}

.filter-chip {
  font-family: var(--font-body);
  font-size: var(--text-sm);
  letter-spacing: 0.08em;
  padding: 7px var(--space-2);
  border: var(--border-thin) solid transparent;
  border-radius: var(--radius-sm);
  background-color: var(--color-primary-soft);
  color: var(--color-ink-soft);
  cursor: pointer;
  transition: color 140ms ease, background-color 140ms ease, border-color 140ms ease;
}

.filter-chip:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.filter-chip[aria-pressed="true"] {
  background-color: var(--color-primary);
  border-color: var(--color-primary);
  color: var(--color-primary-ink);
}

/* ===== reveal ===== */
.reveal {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 200ms ease, transform 200ms ease;
}

.reveal.is-in {
  opacity: 1;
  transform: none;
}

/* ===== fixed chrome ===== */
.read-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: var(--border-thick);
  width: 0;
  background-color: var(--color-accent);
  z-index: 80;
  pointer-events: none;
}

.to-top {
  position: fixed;
  right: var(--space-3);
  bottom: var(--space-3);
  z-index: 70;
  padding: 10px var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.14em;
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  background-color: var(--color-surface);
  color: var(--color-ink-soft);
  box-shadow: var(--shadow-1);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity 180ms ease, color 140ms ease, border-color 140ms ease;
}

.to-top[data-visible] {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

.to-top:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* ===== skip link ===== */
.skip-link {
  position: absolute;
  top: var(--space-1);
  left: 50%;
  transform: translate(-50%, -160%);
  z-index: 100;
  padding: var(--space-2) var(--space-3);
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  letter-spacing: 0.08em;
  text-decoration: none;
  transition: transform 160ms ease;
}

.skip-link:focus {
  transform: translate(-50%, 0);
  color: var(--color-contrast-ink);
}

/* ===== header ===== */
.site-header {
  position: relative;
  background-color: var(--color-surface);
  padding-top: var(--space-2);
}

.masthead {
  padding-block: var(--space-2) var(--space-3);
}

.masthead__meta {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: var(--space-2);
}

.masthead__stamp {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--color-ink-muted);
}

.masthead__utility {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: flex-end;
  gap: var(--space-2);
}

.masthead__title {
  margin-block: var(--space-3) var(--space-2);
  text-align: center;
}

.masthead__brand {
  display: inline-block;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: clamp(var(--text-2xl), 6.4vw, var(--text-3xl));
  line-height: 1.05;
  letter-spacing: 0.16em;
  text-indent: 0.16em;
  color: var(--color-ink);
  text-decoration: none;
}

.masthead__brand:hover { color: var(--color-primary); }

.masthead__tagline {
  text-align: center;
  font-size: var(--text-sm);
  letter-spacing: 0.22em;
  color: var(--color-ink-muted);
}

.header-rule {
  height: calc(var(--border-thin) * 4);
  border-top: var(--border-thin) solid var(--color-ink);
  border-bottom: var(--border-thin) solid var(--color-ink);
}

.site-nav { padding-block: var(--space-2) var(--space-3); }

.site-nav__inner { display: flex; justify-content: center; }

.site-nav__list {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: var(--space-4);
}

.nav-link {
  position: relative;
  display: inline-block;
  padding-block: var(--space-1);
  font-family: var(--font-heading);
  font-size: var(--text-base);
  letter-spacing: 0.1em;
  color: var(--color-ink-soft);
  text-decoration: none;
  transition: color 140ms ease;
}

.nav-link:hover { color: var(--color-accent); }

.nav-link[aria-current="page"] { color: var(--color-ink); }

.nav-link[aria-current="page"]::before {
  content: "";
  position: absolute;
  left: -12px;
  top: 50%;
  transform: translateY(-50%);
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background-color: var(--color-accent);
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: var(--space-1);
  padding: 7px var(--space-2);
  border: var(--border-thin) solid var(--color-ink-soft);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.16em;
  color: var(--color-ink);
  cursor: pointer;
}

.nav-toggle__bars {
  display: block;
  width: 14px;
  height: 8px;
  border-top: var(--border-thin) solid currentColor;
  border-bottom: var(--border-thin) solid currentColor;
}

.nav-toggle[aria-expanded="true"] {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* ===== footer ===== */
.site-footer { background-color: var(--color-surface); }

.footer-index {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  padding-block: var(--section-y);
  border-bottom: calc(var(--border-thick) * 2) double var(--color-contrast-line);
}

.footer-index__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-2);
  padding-bottom: var(--space-4);
}

.footer-title {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-xl);
  letter-spacing: 0.12em;
  color: var(--color-contrast-ink);
}

.footer-index__note {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.24em;
  color: var(--color-contrast-accent);
}

.footer-cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--gutter);
}

.footer-col__title {
  margin-bottom: var(--space-3);
  font-family: var(--font-mono);
  font-weight: var(--weight-body);
  font-size: var(--text-xs);
  letter-spacing: 0.26em;
  text-transform: uppercase;
  color: var(--color-contrast-accent);
}

.footer-list { display: grid; gap: var(--space-2); }

.footer-link {
  display: inline-block;
  padding-bottom: 2px;
  font-size: var(--text-sm);
  letter-spacing: 0.06em;
  color: var(--color-contrast-ink);
  text-decoration: none;
  border-bottom: var(--border-thin) solid transparent;
  transition: color 140ms ease, border-color 140ms ease;
}

.footer-link:hover {
  color: var(--color-contrast-accent);
  border-bottom-color: var(--color-contrast-accent);
}

.footer-contact { margin-top: var(--space-4); }

.footer-contact__label {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.2em;
  color: color-mix(in srgb, var(--color-contrast-ink) 58%, transparent);
}

.footer-contact__value {
  margin-bottom: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  letter-spacing: 0.06em;
  color: var(--color-contrast-ink);
}

.footer-legal {
  background-color: var(--color-surface-deep);
  padding-block: var(--space-4);
}

.footer-legal__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2) var(--space-4);
}

.footer-meta {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  color: var(--color-ink-muted);
}

.footer-meta--license { color: var(--color-ink-soft); }

.footer-legal__links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
}

.footer-link--quiet { color: var(--color-ink-soft); }

.footer-link--quiet:hover {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
}

/* ===== responsive ===== */
@media (max-width: 1024px) {
  .span-3 { grid-column: span 6; }
  .footer-cols { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-col:last-child { grid-column: span 2; }
}

@media (max-width: 880px) {
  .container { width: min(100% - calc(var(--space-2) * 2), var(--container)); }

  .nav-toggle { display: inline-flex; }

  .site-nav {
    display: none;
    padding-bottom: 0;
    background-color: var(--color-surface-alt);
  }

  .site-nav[data-open] { display: block; }

  .site-nav__inner { display: block; }

  .site-nav__list {
    display: grid;
    grid-template-columns: 1fr;
    gap: 0;
    padding-block: var(--space-1);
  }

  .site-nav__list li { border-bottom: var(--border-thin) solid var(--color-line); }

  .nav-link {
    display: block;
    padding: var(--space-2) var(--space-3);
    font-size: var(--text-base);
  }

  .nav-link[aria-current="page"] {
    padding-left: var(--space-6);
    background-color: var(--color-primary-soft);
  }

  .nav-link[aria-current="page"]::before { left: var(--space-3); }

  .span-3, .span-4, .span-6, .span-8 { grid-column: span 12; }
}

@media (max-width: 720px) {
  .masthead__meta { grid-template-columns: 1fr; justify-items: start; }
  .masthead__utility { justify-content: space-between; width: 100%; }
  .footer-index { padding-block: var(--section-y); }
  .footer-cols { grid-template-columns: 1fr; }
  .footer-col:last-child { grid-column: auto; }
  .footer-index__head { flex-direction: column; gap: var(--space-1); }
  .footer-legal__inner { flex-direction: column; align-items: flex-start; }
}

@media (max-width: 520px) {
  .masthead__hours { display: none; }
  .masthead__utility .btn { display: none; }
  .masthead__tagline { letter-spacing: 0.14em; }
  .footer-legal__links { flex-direction: column; gap: var(--space-1); }
}

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

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }

  .skip-link { transition: none; }
}