/* Platform operations — Gehua Dongyang layered folder archive */
.dongyang-section {
  position: relative;
  min-height: 118vh;
  background: #f2efe7;
  color: #111214;
  scroll-snap-align: start;
  isolation: isolate;
}

.dongyang-section::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 38vh;
  z-index: 1;
  pointer-events: none;
  background: linear-gradient(to bottom, #050506 0%, #363535 22%, #b9b6af 58%, rgba(242,239,231,0) 100%);
}

.dongyang-sticky {
  position: sticky;
  top: 0;
  height: 100vh;
  min-height: 650px;
  overflow: hidden;
  background:
    linear-gradient(rgba(25,28,33,.055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(25,28,33,.055) 1px, transparent 1px),
    #f2efe7;
  background-size: 30px 30px;
}

.dongyang-sticky::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 2;
  background:
    radial-gradient(circle at 50% 70%, rgba(77,69,56,.09), transparent 34%),
    linear-gradient(to bottom, rgba(255,255,255,.3), transparent 32%);
  mix-blend-mode: multiply;
}

.dongyang-heading {
  position: absolute;
  left: 4.2vw;
  top: 12vh;
  z-index: 20;
  width: min(36vw, 470px);
}

.dongyang-heading .eyebrow {
  margin: 0 0 13px;
  opacity: .62;
}

.dongyang-heading h2 {
  margin: 0;
  font-size: clamp(42px, 5.8vw, 86px);
  line-height: .88;
  letter-spacing: -.065em;
  font-weight: 500;
}

.dongyang-heading > p:last-child {
  width: min(360px, 90%);
  margin: 18px 0 0;
  font: 400 10px/1.7 "IBM Plex Mono", monospace;
  text-transform: uppercase;
  opacity: .62;
}

.dongyang-meta {
  position: absolute;
  right: 4.2vw;
  top: 13vh;
  z-index: 20;
  display: grid;
  justify-items: end;
  gap: 7px;
  font: 500 9px/1.3 "IBM Plex Mono", monospace;
  letter-spacing: .06em;
}

.dongyang-meta b { font-size: 12px; font-weight: 500; }
.dongyang-meta span { opacity: .48; }

.dongyang-stack {
  position: absolute;
  left: 50%;
  top: 50%;
  z-index: 10;
  width: min(72vw, 940px);
  height: min(63vh, 590px);
  transform: translate(-50%, -37%);
  perspective: 1500px;
}

.dongyang-folder {
  --folder-index: 0;
  --folder-shift: 0px;
  position: absolute;
  left: 50%;
  top: calc(var(--folder-index) * 66px);
  width: 100%;
  height: 390px;
  color: #111214;
  transform: translateX(-50%) translateY(var(--folder-shift));
  transform-style: preserve-3d;
  transition:
    transform .72s cubic-bezier(.22,1,.36,1),
    filter .45s ease,
    opacity .35s ease;
  z-index: calc(5 + var(--folder-index));
  outline: none;
}

.dongyang-folder.is-open {
  z-index: 30;
  transform: translateX(-50%) translateY(-68px) scale(1.015);
  filter: drop-shadow(0 28px 38px rgba(48,43,35,.18));
}

.dongyang-stack.has-open-folder .dongyang-folder:not(.is-open) {
  opacity: .72;
  filter: grayscale(.15);
}

.dongyang-folder-back {
  position: absolute;
  inset: 0;
  border: 2px solid #17181b;
  border-radius: 10px 10px 18px 18px;
  background: #f7f5ef;
  box-shadow: 0 5px 0 rgba(17,18,20,.06);
  overflow: visible;
}

.dongyang-tab {
  position: absolute;
  top: -39px;
  left: calc(5% + var(--folder-index) * 17%);
  min-width: 150px;
  height: 41px;
  padding: 0 18px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  border: 2px solid #17181b;
  border-bottom: 0;
  border-radius: 13px 13px 0 0;
  background: #f7f5ef;
  font: 500 10px/1 "IBM Plex Mono", monospace;
}

.dongyang-tab b { font-weight: 500; }
.dongyang-tab span { opacity: .52; }

.dongyang-file-content {
  position: absolute;
  left: 4.5%;
  right: 4.5%;
  top: 4.5%;
  bottom: 23%;
  display: grid;
  grid-template-columns: .72fr 1.28fr;
  gap: 4vw;
  align-items: center;
  opacity: 0;
  transform: translateY(34px) scale(.98);
  pointer-events: none;
  transition: opacity .35s .08s ease, transform .65s .05s cubic-bezier(.22,1,.36,1);
}

.dongyang-folder.is-open .dongyang-file-content {
  opacity: 1;
  transform: translateY(0) scale(1);
  pointer-events: auto;
}

.dongyang-file-copy {
  align-self: center;
  padding-left: 1vw;
}

.dongyang-file-copy > span {
  display: block;
  margin-bottom: 17px;
  font: 500 9px/1 "IBM Plex Mono", monospace;
  opacity: .5;
}

.dongyang-file-copy h3 {
  margin: 0;
  font-size: clamp(28px, 3.7vw, 56px);
  line-height: .92;
  letter-spacing: -.055em;
  font-weight: 700;
}

.dongyang-file-copy p {
  margin: 20px 0 0;
  max-width: 320px;
  font: 400 10px/1.65 "IBM Plex Mono", monospace;
  text-transform: uppercase;
  opacity: .6;
}

.dongyang-player {
  position: relative;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  border: 2px solid #17181b;
  background: #d9d7d1;
  box-shadow: 10px 12px 0 rgba(17,18,20,.08);
}

.dongyang-player img,
.dongyang-player video {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.dongyang-player img {
  filter: grayscale(.18) saturate(.75) contrast(1.03);
  transition: opacity .25s ease;
}

.dongyang-player video { opacity: 0; }
.dongyang-folder.is-video-ready .dongyang-player img { opacity: 0; }
.dongyang-folder.is-video-ready .dongyang-player video { opacity: 1; }

.dongyang-player::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    linear-gradient(120deg, rgba(255,255,255,.18), transparent 23%),
    repeating-linear-gradient(to bottom, rgba(255,255,255,.07) 0 1px, transparent 1px 4px);
  mix-blend-mode: soft-light;
}

.dongyang-player-ui {
  position: absolute;
  left: 10px;
  right: 10px;
  bottom: 9px;
  z-index: 4;
  display: flex;
  justify-content: space-between;
  color: #fff;
  font: 500 8px/1 "IBM Plex Mono", monospace;
  text-shadow: 0 1px 4px rgba(0,0,0,.7);
}

.dongyang-player-ui span::before {
  content: "";
  display: inline-block;
  width: 6px;
  height: 6px;
  margin-right: 6px;
  border-radius: 50%;
  background: #f45a4b;
}

.dongyang-folder-front {
  position: absolute;
  left: -2px;
  right: -2px;
  top: 86px;
  bottom: -2px;
  z-index: 8;
  display: grid;
  grid-template-columns: 100px 1fr auto;
  align-items: start;
  gap: 20px;
  padding: 27px 30px;
  border: 2px solid #17181b;
  border-radius: 8px 8px 18px 18px;
  background:
    linear-gradient(rgba(20,22,26,.045) 1px, transparent 1px),
    #f2efe7;
  background-size: 100% 26px;
  transform-origin: center bottom;
  transform: translateY(0) rotateX(0deg);
  transition: transform .78s cubic-bezier(.22,1,.36,1), box-shadow .5s ease;
}

.dongyang-folder.is-open .dongyang-folder-front {
  transform: translateY(255px) rotateX(-7deg);
  box-shadow: 0 -8px 25px rgba(17,18,20,.07);
}

.dongyang-folder-front > span,
.dongyang-folder-front > em {
  font: 500 9px/1 "IBM Plex Mono", monospace;
  opacity: .52;
}

.dongyang-folder-front > b {
  font-size: clamp(18px, 2vw, 30px);
  line-height: 1;
  font-weight: 500;
  letter-spacing: -.04em;
}

.dongyang-folder-front > em {
  font-style: normal;
  justify-self: end;
}

.dongyang-instruction {
  position: absolute;
  left: 4.2vw;
  right: 4.2vw;
  bottom: 4.5vh;
  z-index: 20;
  display: grid;
  grid-template-columns: 90px auto 1fr;
  align-items: center;
  gap: 12px;
  font: 500 8px/1 "IBM Plex Mono", monospace;
}

.dongyang-instruction > span { height: 1px; background: currentColor; }
.dongyang-instruction > b { font-weight: 500; }
.dongyang-instruction > em { justify-self: end; font-style: normal; opacity: .48; }

/* English-only typography: keep long labels from colliding with folders. */
.dongyang-section.is-en .dongyang-heading {
  top: 13.5vh;
  width: min(31vw, 430px);
}
.dongyang-section.is-en .dongyang-heading h2 {
  font-size: clamp(30px, 3.4vw, 52px);
  line-height: .96;
  letter-spacing: -.045em;
}
.dongyang-section.is-en .dongyang-heading > p:last-child {
  width: min(420px, 100%);
  margin-top: 14px;
  font-size: 8px;
  line-height: 1.55;
  letter-spacing: .035em;
}
.dongyang-section.is-en .dongyang-meta {
  top: 14vh;
  font-size: 8px;
}
.dongyang-section.is-en .dongyang-meta b {
  font-size: 10px;
}
.dongyang-section.is-en .dongyang-file-content {
  grid-template-columns: .86fr 1.14fr;
  gap: 3vw;
}
.dongyang-section.is-en .dongyang-file-copy > span {
  margin-bottom: 11px;
  font-size: 7px;
}
.dongyang-section.is-en .dongyang-file-copy h3 {
  font-size: clamp(19px, 2.25vw, 34px);
  line-height: 1.06;
  letter-spacing: -.035em;
  font-weight: 600;
}
.dongyang-section.is-en .dongyang-file-copy p {
  margin-top: 13px;
  max-width: 360px;
  font-size: 8px;
  line-height: 1.5;
}
.dongyang-section.is-en .dongyang-folder-front > b {
  font-size: clamp(14px, 1.45vw, 22px);
  line-height: 1.08;
  letter-spacing: -.025em;
}
.dongyang-section.is-en .dongyang-folder-front > span,
.dongyang-section.is-en .dongyang-folder-front > em {
  font-size: 8px;
}

body.is-dongyang-section .site-header {
  color: #111214;
  border-bottom-color: rgba(17,18,20,.1);
  transition: color .45s ease, border-color .45s ease;
}

body.is-dongyang-section .cursor-dot { color: #111214; }

@media (max-width: 920px) {
  .dongyang-heading { width: 44vw; }
  .dongyang-meta { display: none; }
  .dongyang-stack { width: 86vw; transform: translate(-50%, -33%); }
  .dongyang-file-content { grid-template-columns: .8fr 1.2fr; gap: 26px; }
  .dongyang-folder-front { grid-template-columns: 74px 1fr auto; }
  .dongyang-section.is-en .dongyang-heading { width: 40vw; }
  .dongyang-section.is-en .dongyang-file-content { grid-template-columns: .9fr 1.1fr; gap: 20px; }
}

@media (max-width: 640px) {
  .dongyang-section { min-height: 112vh; }
  .dongyang-sticky { min-height: 650px; }
  .dongyang-heading { left: 18px; top: 9vh; width: calc(100vw - 36px); }
  .dongyang-heading h2 { font-size: 45px; }
  .dongyang-heading > p:last-child { width: 280px; }
  .dongyang-stack { width: calc(100vw - 28px); height: 500px; top: 48%; transform: translate(-50%, -26%); }
  .dongyang-folder { top: calc(var(--folder-index) * 55px); height: 350px; }
  .dongyang-folder.is-open { transform: translateX(-50%) translateY(-52px) scale(1); }
  .dongyang-tab { min-width: 98px; left: calc(2% + var(--folder-index) * 18%); padding: 0 10px; }
  .dongyang-tab b { display: none; }
  .dongyang-file-content { left: 6%; right: 6%; top: 6%; bottom: 19%; grid-template-columns: 1fr; gap: 14px; align-content: start; }
  .dongyang-file-copy { padding: 0; }
  .dongyang-file-copy h3 { font-size: 31px; }
  .dongyang-file-copy p { display: none; }
  .dongyang-file-copy > span { margin-bottom: 8px; }
  .dongyang-player { width: 100%; }
  .dongyang-folder-front { top: 75px; padding: 20px 17px; grid-template-columns: 52px 1fr; }
  .dongyang-folder-front > em { display: none; }
  .dongyang-folder.is-open .dongyang-folder-front { transform: translateY(238px) rotateX(-5deg); }
  .dongyang-instruction { left: 18px; right: 18px; }
  .dongyang-section.is-en .dongyang-heading { left: 18px; top: 10vh; width: calc(100vw - 36px); }
  .dongyang-section.is-en .dongyang-heading h2 { font-size: 34px; }
  .dongyang-section.is-en .dongyang-file-copy h3 { font-size: 22px; }
}

@media (prefers-reduced-motion: reduce) {
  .dongyang-folder,
  .dongyang-folder-front,
  .dongyang-file-content { transition-duration: .01ms !important; }
}