.site-header {
  height: calc(94px + env(safe-area-inset-top, 0px));
  position: fixed;
  left: 0;
  top: 0;
  right: 0;
  z-index: 30;
  display: flex;
  align-items: center;
  gap: 40px;
  padding: env(safe-area-inset-top, 0px) 4.5vw 0;
  transition:
    color 0.5s,
    background 0.5s;
  background: linear-gradient(#14201866, transparent);
}
.brand {
  display: flex;
  align-items: center;
  gap: 13px;
  flex: none;
  font: 21px var(--serif);
  letter-spacing: 0.14em;
}
.brand small {
  display: block;
  font:
    8px/2 Consolas,
    monospace;
  letter-spacing: 0.13em;
  margin-top: 4px;
}
.seal {
  border: 1px solid #c18369;
  color: #d5a387;
  font: 30px/1 var(--serif);
  width: 40px;
  height: 44px;
  display: grid;
  place-items: center;
}
.edition {
  font:
    9px/1.7 Consolas,
    monospace;
  color: var(--muted);
  letter-spacing: 0.08em;
}
.site-header nav {
  margin-left: auto;
  display: flex;
  gap: 23px;
}
.site-header nav button {
  position: relative;
  font-size: 11px;
  padding: 12px 0;
}
.site-header nav button:after {
  content: '';
  position: absolute;
  bottom: 2px;
  left: 50%;
  width: 3px;
  height: 3px;
  background: currentColor;
  opacity: 0;
  translate: -50% 4px;
  transition:
    opacity 0.35s var(--ease),
    translate 0.35s var(--ease);
}
.site-header nav button.is-active:after {
  opacity: 1;
  translate: -50% 0;
}
.menu-toggle {
  display: none;
}
.menu-toggle span {
  display: inline-block;
  transition: rotate 0.4s var(--ease);
}
.menu-open .menu-toggle span {
  rotate: 45deg;
}
.scene {
  position: absolute;
  inset: 0;
  height: 100vh;
  height: 100dvh;
  overflow: hidden;
  visibility: hidden;
  pointer-events: none;
  opacity: 0;
  background: var(--bg);
  isolation: isolate;
  transition:
    opacity 0.75s var(--ease),
    transform 0.82s var(--ease),
    translate 0.55s var(--ease),
    visibility 0.82s;
  transform: translateY(4%);
  /* Live finger offset from touch drags; springs back via the translate transition. */
  translate: var(--swipe-x, 0px) var(--drag-y, 0px);
}
.scene.is-active,
.scene.is-leaving {
  will-change: opacity, transform;
}
body.is-dragging .scene.is-active {
  transition:
    opacity 0.75s var(--ease),
    transform 0.82s var(--ease),
    visibility 0.82s;
}
.scene.is-active {
  visibility: visible;
  pointer-events: auto;
  opacity: 1;
  transform: none;
  z-index: 2;
}
.scene.is-leaving {
  visibility: visible;
  opacity: 0;
  transform: translateY(-4%);
  z-index: 1;
}
.scene.is-leaving * {
  pointer-events: none !important;
}
body[data-direction='back'] .scene:not(.is-active) {
  transform: translateY(-4%);
}
body[data-direction='back'] .scene.is-leaving {
  transform: translateY(4%);
}
main {
  height: 100%;
  outline: none;
}
.scene-image {
  position: absolute;
  inset: -2%;
  background-size: cover;
  background-position: center;
  z-index: -3;
}
.chapter-copy {
  position: absolute;
  left: 8vw;
  top: 50%;
  translate: 0 -48%;
  width: 32%;
  z-index: 5;
}
.giant-index {
  position: absolute;
  bottom: 30px;
  left: 6vw;
  font: 200px/1 var(--serif);
  color: #c1cbb80b;
  pointer-events: none;
}
.exhibition-footer {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  height: calc(60px + env(safe-area-inset-bottom, 0px));
  z-index: 30;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 4.5vw env(safe-area-inset-bottom, 0px);
  transition: background 0.5s;
  font:
    9px Consolas,
    monospace;
  letter-spacing: 0.1em;
  background: linear-gradient(transparent, #12201677);
}
.exhibition-footer > div {
  display: flex;
  align-items: center;
  gap: 20px;
}
.footer-nav button {
  font: 22px var(--serif);
  padding: 10px;
}
/* Thin exhibition progress line along the top edge of the footer. */
.scene-progress {
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 1px;
  background: var(--line);
  pointer-events: none;
}
.scene-progress i {
  display: block;
  height: 100%;
  background: var(--accent);
  transform-origin: left;
  transform: scaleX(var(--scene-progress, 0.125));
  transition: transform 0.82s var(--ease);
}
.exhibition-footer #navigation-hint.is-updating {
  animation: hint-in 0.5s var(--ease);
}
@keyframes hint-in {
  from {
    opacity: 0;
    translate: 0 6px;
  }
}
.exhibition-footer #navigation-hint {
  font:
    10px 'Microsoft YaHei',
    sans-serif;
  letter-spacing: 0.1em;
}
.vertical-note {
  position: absolute;
  right: 4.5vw;
  top: 38%;
  writing-mode: vertical-rl;
  font: 11px/2 var(--serif);
  letter-spacing: 0.3em;
}
.hero-footnote {
  position: absolute;
  bottom: 86px;
  left: 8vw;
  right: 8vw;
  display: flex;
  justify-content: space-between;
  font-size: 9px;
  letter-spacing: 0.14em;
}
body[data-scene='2'],
body[data-scene='4'] {
  --paper: #2a382b;
  --muted: #6c7362;
  --line: #29352630;
}
body[data-scene='2'] .site-header,
body[data-scene='4'] .site-header {
  background: linear-gradient(#e8e2d6bb, transparent);
}
body[data-scene='2'] .exhibition-footer,
body[data-scene='4'] .exhibition-footer {
  background: linear-gradient(transparent, #e8e2d6bb);
}
body[data-scene='2'] .seal,
body[data-scene='4'] .seal {
  color: #a35b40;
}
body[data-scene='2'] .brand,
body[data-scene='4'] .brand {
  color: #263629;
}