:root {
  --ink: #1b1a18;
  --ink-soft: #45423d;
  --paper: #e9e5dc;
  --paper-deep: #dcd6ca;
  --night: #191816;
  --night-2: #0f0f0e;
  --ash: #aaa59a;
  --ember: #a8482c;
  --ember-bright: #c35a36;
  --bone: #ddd6c9;
  --line-light: rgba(31, 29, 26, 0.18);
  --line-dark: rgba(235, 230, 219, 0.18);
  --page-pad: clamp(1.4rem, 4.3vw, 5.25rem);
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
  --ease-in-out: cubic-bezier(0.76, 0, 0.24, 1);
  --chapter-progress: 0;
  color-scheme: light dark;
  font-synthesis: none;
}

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

html {
  scroll-behavior: smooth;
  background: var(--night);
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: "Helvetica Neue", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  font-weight: 400;
  overflow-x: hidden;
}

body.motion-paused *,
body.motion-paused *::before,
body.motion-paused *::after {
  animation-play-state: paused !important;
}

a {
  color: inherit;
  text-decoration: none;
}

button {
  color: inherit;
  font: inherit;
}

::selection {
  color: var(--paper);
  background: var(--ember);
}

.skip-link {
  position: fixed;
  z-index: 1000;
  top: 0.75rem;
  left: 0.75rem;
  padding: 0.7rem 1rem;
  color: var(--paper);
  background: var(--ink);
  transform: translateY(-160%);
  transition: transform 180ms ease;
}

.skip-link:focus {
  transform: translateY(0);
}

.grain {
  position: fixed;
  z-index: 90;
  inset: -50%;
  width: 200%;
  height: 200%;
  pointer-events: none;
  opacity: 0.045;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 180 180' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='.75'/%3E%3C/svg%3E");
  animation: grain-shift 0.22s steps(2) infinite;
}

@keyframes grain-shift {
  0% { transform: translate3d(-2%, 1%, 0); }
  25% { transform: translate3d(1%, -2%, 0); }
  50% { transform: translate3d(2%, 2%, 0); }
  75% { transform: translate3d(-1%, -1%, 0); }
  100% { transform: translate3d(0, 2%, 0); }
}

.site-header {
  position: fixed;
  z-index: 80;
  top: 0;
  left: 0;
  display: flex;
  justify-content: flex-end;
  align-items: center;
  width: 100%;
  padding: 1.25rem var(--page-pad);
  color: var(--paper);
  mix-blend-mode: difference;
  pointer-events: none;
}

.site-header button {
  pointer-events: auto;
}

.chapter-progress {
  position: absolute;
  left: 50%;
  display: flex;
  align-items: center;
  gap: 0.7rem;
  font-variant-numeric: tabular-nums;
  font-size: 0.68rem;
  letter-spacing: 0.08em;
  transform: translateX(-50%);
}

.progress-line {
  position: relative;
  width: clamp(4rem, 9vw, 8rem);
  height: 1px;
  overflow: hidden;
  background: rgba(255, 255, 255, 0.24);
}

.progress-line i {
  position: absolute;
  inset: 0;
  background: currentColor;
  transform: scaleX(var(--chapter-progress));
  transform-origin: left;
}

.chapter-rail {
  position: fixed;
  z-index: 75;
  top: 50%;
  right: calc(var(--page-pad) * 0.45);
  color: var(--paper);
  mix-blend-mode: difference;
  transform: translateY(-50%);
}

.chapter-rail ol {
  display: grid;
  gap: 0.55rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.chapter-rail a {
  position: relative;
  display: block;
  width: 1.1rem;
  height: 0.55rem;
}

.chapter-rail a::before {
  position: absolute;
  top: 50%;
  right: 0;
  width: 0.45rem;
  height: 1px;
  background: currentColor;
  opacity: 0.35;
  content: "";
  transform: translateY(-50%);
  transition: width 350ms var(--ease-out), opacity 350ms ease;
}

.chapter-rail a:hover::before,
.chapter-rail a.is-active::before {
  width: 1.1rem;
  opacity: 1;
}

.chapter-rail a.is-active::after {
  position: absolute;
  top: 50%;
  right: 1.5rem;
  content: attr(data-index);
  font-size: 0.58rem;
  font-variant-numeric: tabular-nums;
  transform: translateY(-50%);
}

.chapter-rail span {
  position: absolute;
  top: 50%;
  right: 2.55rem;
  width: max-content;
  opacity: 0;
  pointer-events: none;
  font-size: 0.65rem;
  transform: translate(0.5rem, -50%);
  transition: opacity 250ms ease, transform 300ms var(--ease-out);
}

.chapter-rail a:hover span {
  opacity: 0.7;
  transform: translate(0, -50%);
}

.hero,
.chapter {
  position: relative;
  min-height: 100svh;
  overflow: clip;
}

.dark-section {
  color: var(--bone);
  background: var(--night);
}

.light-section {
  color: var(--ink);
  background: var(--paper);
}

.hero {
  min-height: 100svh;
  isolation: isolate;
}

.hero-image {
  position: absolute;
  z-index: -3;
  inset: -6%;
  background-image: url("../assets/ember-tree.png");
  background-position: center;
  background-size: cover;
  filter: saturate(0.72) contrast(1.04);
  transform: scale(1.06) translate3d(0, calc(var(--hero-parallax, 0) * 1px), 0);
  will-change: transform;
}

.hero-shade {
  position: absolute;
  z-index: -2;
  inset: 0;
  background:
    linear-gradient(90deg, rgba(9, 9, 8, 0.82) 0%, rgba(10, 10, 9, 0.55) 46%, rgba(10, 10, 9, 0.2) 77%),
    linear-gradient(0deg, rgba(9, 9, 8, 0.85) 0%, transparent 50%),
    radial-gradient(circle at 72% 45%, transparent 0%, rgba(10, 10, 9, 0.28) 55%, rgba(8, 8, 7, 0.6) 100%);
}

.hero-copy {
  position: absolute;
  top: 50%;
  left: var(--page-pad);
  width: min(70rem, calc(100% - var(--page-pad) * 2));
  transform: translateY(-46%);
}

.eyebrow {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin: 0 0 2.2rem;
  color: rgba(233, 229, 220, 0.64);
  font-family: "Songti SC", "STSong", serif;
  font-size: 0.82rem;
  letter-spacing: 0.25em;
}

.eyebrow[lang="en"] {
  font-family: "Helvetica Neue", Arial, sans-serif;
  letter-spacing: 0.13em;
}

.eyebrow::before {
  width: 2.4rem;
  height: 1px;
  background: var(--ember);
  content: "";
}

.hero-title {
  margin: 0;
  font-weight: 400;
  line-height: 0.78;
  letter-spacing: -0.07em;
}

.title-en,
.title-cn {
  display: block;
  width: max-content;
}

.title-en {
  color: #d7d0c3;
  font-family: "Times New Roman", "Songti SC", serif;
  font-size: clamp(5.5rem, 17vw, 16rem);
}

.title-cn {
  margin-top: 0.2em;
  margin-left: 0.05em;
  color: var(--ember);
  font-family: "Songti SC", "STSong", serif;
  font-size: clamp(2.5rem, 6.5vw, 6.5rem);
  letter-spacing: 0.35em;
}

.word-reveal {
  clip-path: inset(0 100% 0 0);
  animation: title-draw 1.5s 0.15s var(--ease-out) forwards;
}

.title-cn.word-reveal {
  animation-delay: 0.72s;
}

@keyframes title-draw {
  to { clip-path: inset(0 0 0 0); }
}

.scroll-cue {
  position: absolute;
  bottom: 3.4rem;
  left: var(--page-pad);
  display: flex;
  align-items: center;
  gap: 0.8rem;
  color: rgba(233, 229, 220, 0.65);
  font-size: 0.65rem;
  letter-spacing: 0.14em;
}

.scroll-cue span {
  color: var(--ember);
  font-size: 1rem;
  animation: scroll-arrow 2.2s var(--ease-in-out) infinite;
}

@keyframes scroll-arrow {
  50% { transform: translateY(0.45rem); }
}

.chapter {
  min-height: clamp(48rem, 110svh, 72rem);
  padding: clamp(7.5rem, 14vh, 11rem) var(--page-pad) 5rem;
}

.chapter-grid {
  position: relative;
  z-index: 2;
  display: grid;
  grid-template-columns: minmax(9rem, 0.7fr) minmax(14rem, 1.45fr) minmax(12rem, 0.85fr);
  grid-template-rows: auto 1fr auto;
  gap: 2rem clamp(2rem, 6vw, 7rem);
  width: min(100%, 92rem);
  min-height: calc(clamp(48rem, 110svh, 72rem) - clamp(12.5rem, 14vh + 5rem, 16rem));
  margin: 0 auto;
}

.chapter-heading {
  z-index: 3;
  grid-column: 1 / 3;
  grid-row: 1;
}

.chapter-index {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  margin: 0 0 1.6rem;
  font-size: 0.65rem;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.1em;
}

.chapter-index::after {
  width: 2.5rem;
  height: 1px;
  background: currentColor;
  opacity: 0.32;
  content: "";
}

.chapter-heading h2 {
  margin: 0;
  font-family: "Songti SC", "STSong", serif;
  font-size: clamp(2.7rem, 5.7vw, 6rem);
  font-weight: 400;
  line-height: 1;
  letter-spacing: -0.04em;
}

.chapter-heading h2[lang="en"] {
  font-family: "Times New Roman", Georgia, serif;
  letter-spacing: -0.055em;
}

.chapter-statement {
  align-self: end;
  grid-column: 1 / 4;
  grid-row: 3;
}

.chapter-statement p {
  margin: 0;
  font-family: "Songti SC", "STSong", serif;
  font-size: clamp(2.15rem, 5vw, 5.4rem);
  line-height: 1.18;
  letter-spacing: -0.045em;
}

.chapter-statement p[lang="en"] {
  font-family: "Times New Roman", Georgia, serif;
}

.chapter-statement.is-quote p {
  max-width: 24ch;
  font-family: "Times New Roman", Georgia, serif;
  font-size: clamp(2.25rem, 4.4vw, 4.8rem);
  line-height: 1.04;
  letter-spacing: -0.04em;
}

.chapter-statement.is-small-quote {
  max-width: min(58vw, 49rem);
}

.chapter-statement.is-small-quote p {
  opacity: 0.76;
  font-family: "Times New Roman", Georgia, serif;
  font-size: clamp(0.95rem, 1.35vw, 1.22rem);
  line-height: 1.55;
  letter-spacing: -0.01em;
}

.reveal {
  opacity: 0;
  transform: translateY(1.5rem);
  transition: opacity 900ms ease, transform 1.1s var(--ease-out);
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

.restraint-stage {
  position: relative;
  align-self: center;
  grid-column: 2 / 4;
  grid-row: 2;
  height: clamp(19rem, 34vw, 29rem);
  perspective: 1200px;
}

.magic-table {
  position: absolute;
  top: 50%;
  left: 50%;
  width: min(100%, 42rem);
  height: 100%;
  transform: translate(-50%, -50%);
  transform-style: preserve-3d;
}

.magic-card {
  --lift: 0rem;
  position: absolute;
  top: 50%;
  left: 50%;
  width: clamp(7.2rem, 11vw, 10rem);
  aspect-ratio: 5 / 7;
  padding: 0;
  border: 0;
  background: transparent;
  cursor: pointer;
  transform-style: preserve-3d;
  transition: transform 780ms var(--ease-in-out), filter 500ms ease;
}

.magic-card[data-slot="-1"] {
  z-index: 1;
  transform: translateX(-165%) translateY(calc(-50% + var(--lift))) rotate(-7deg);
}

.magic-card[data-slot="0"] {
  z-index: 3;
  transform: translateX(-50%) translateY(calc(-50% + var(--lift)));
}

.magic-card[data-slot="1"] {
  z-index: 2;
  transform: translateX(65%) translateY(calc(-50% + var(--lift))) rotate(7deg);
}

.magic-card:hover,
.magic-card:focus-visible,
.magic-card.is-selected {
  --lift: -0.75rem;
}

.magic-card:focus-visible {
  outline: none;
}

.magic-card:focus-visible .card-face {
  box-shadow: 0 0 0 0.22rem rgba(168, 72, 44, 0.14), 0 0.8rem 2rem rgba(37, 32, 27, 0.09);
}

.card-inner {
  position: absolute;
  inset: 0;
  display: block;
  transform-style: preserve-3d;
  transition: transform 720ms var(--ease-in-out);
}

.magic-card.is-facedown .card-inner {
  transform: rotateY(180deg);
}

.card-face {
  position: absolute;
  inset: 0;
  display: block;
  overflow: hidden;
  border: 1px solid rgba(27, 26, 24, 0.6);
  border-radius: 0.28rem;
  background: #f0ece3;
  box-shadow: 0 0.8rem 2rem rgba(37, 32, 27, 0.09);
  backface-visibility: hidden;
}

.card-front::after {
  position: absolute;
  inset: 0.42rem;
  border: 1px solid rgba(27, 26, 24, 0.08);
  content: "";
}

.card-front > i,
.card-front > em {
  position: absolute;
  z-index: 2;
  color: var(--ink);
  font-family: "Times New Roman", serif;
  font-size: 0.78rem;
  font-style: normal;
}

.card-front > i {
  top: 0.65rem;
  left: 0.7rem;
}

.card-front > em {
  right: 0.7rem;
  bottom: 0.65rem;
  transform: rotate(180deg);
}

.card-pip {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 2.85rem;
  aspect-ratio: 1;
  border: 1px solid rgba(27, 26, 24, 0.2);
  border-radius: 50%;
  opacity: 0.15;
  transform: translate(-50%, -50%);
  transition: opacity 300ms ease, border-color 300ms ease, background 300ms ease, box-shadow 300ms ease;
}

.card-pip::before,
.card-pip::after {
  position: absolute;
  content: "";
}

.card-pip::before {
  top: 50%;
  left: 50%;
  width: 1px;
  height: 135%;
  background: currentColor;
  opacity: 0.4;
  transform: translate(-50%, -50%) rotate(35deg);
}

.card-pip::after {
  inset: 26%;
  border-radius: 50%;
  background: currentColor;
}

.magic-card.has-ember .card-pip {
  color: var(--ember);
  border-color: var(--ember);
  opacity: 1;
  background: rgba(168, 72, 44, 0.06);
  box-shadow: 0 0 1.4rem rgba(168, 72, 44, 0.16);
}

.card-back {
  background:
    radial-gradient(circle at center, transparent 0 21%, rgba(168, 72, 44, 0.62) 21.5% 22%, transparent 22.5%),
    repeating-conic-gradient(from 0deg at 50% 50%, rgba(168, 72, 44, 0.22) 0 1deg, transparent 1deg 15deg),
    #e5dfd3;
  transform: rotateY(180deg);
}

.card-back::before,
.card-back::after {
  position: absolute;
  content: "";
}

.card-back::before {
  inset: 0.55rem;
  border: 1px solid rgba(168, 72, 44, 0.52);
  border-radius: 50%;
}

.card-back::after {
  top: 50%;
  left: 50%;
  width: 0.42rem;
  height: 0.42rem;
  border-radius: 50%;
  background: var(--ember);
  transform: translate(-50%, -50%);
}

.magic-card.is-facedown.has-ember {
  filter: drop-shadow(0 0.8rem 1rem rgba(168, 72, 44, 0.12));
}

.magic-stage[data-phase="shuffling"] .magic-card {
  pointer-events: none;
}

.magic-whisper {
  position: absolute;
  right: 2%;
  bottom: 0;
  display: flex;
  align-items: center;
  gap: 0.65rem;
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.62rem;
  letter-spacing: 0.1em;
}

.magic-whisper span {
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--ember);
}

.magic-whisper b {
  font-weight: 400;
}

.magic-stage[data-phase="vanished"] .magic-whisper b {
  color: var(--ember);
}

.chapter-posture {
  background:
    radial-gradient(circle at 65% 48%, rgba(168, 72, 44, 0.08), transparent 30%),
    var(--night);
}

.posture-orbit {
  position: absolute;
  top: 50%;
  right: 9%;
  width: min(48vw, 44rem);
  aspect-ratio: 1;
  transform: translateY(-50%);
}

.orbit {
  position: absolute;
  border: 1px solid rgba(224, 216, 201, 0.14);
  border-radius: 50%;
}

.orbit-a {
  inset: 8%;
  transform: rotateX(67deg) rotateZ(calc(22deg + var(--section-progress, 0) * 35deg));
}

.orbit-b {
  inset: 24%;
  transform: rotateY(68deg) rotateZ(calc(-30deg + var(--section-progress, 0) * -35deg));
}

.posture-axis {
  position: absolute;
  top: 8%;
  left: 50%;
  width: 1px;
  height: 84%;
  background: linear-gradient(transparent, rgba(224, 216, 201, 0.32), transparent);
  transform: rotate(calc(-8deg + var(--section-progress, 0) * 16deg));
}

.posture-point {
  position: absolute;
  top: calc(25% + var(--section-progress, 0) * 40%);
  left: calc(66% - var(--section-progress, 0) * 22%);
  width: 0.45rem;
  height: 0.45rem;
  border-radius: 50%;
  background: var(--ember-bright);
  box-shadow: 0 0 1.6rem rgba(195, 90, 54, 0.5);
}

.posture-words {
  position: absolute;
  top: 53%;
  left: 37%;
  z-index: 1;
  width: 55%;
  font-family: "Songti SC", "STSong", serif;
  transform: translateY(-50%);
}

.ghost-output {
  position: absolute;
  top: 50%;
  font-size: clamp(7rem, 16vw, 17rem);
  line-height: 1;
  transform: translateY(-50%);
}

.ghost-output {
  right: -0.05em;
  color: transparent;
  opacity: calc(0.15 - var(--section-progress, 0) * 0.12);
  -webkit-text-stroke: 1px var(--bone);
  filter: blur(calc(var(--section-progress, 0) * 7px));
}

.chapter-cylinder {
  background:
    linear-gradient(90deg, transparent 49.9%, rgba(27, 26, 24, 0.055) 50%, transparent 50.1%),
    var(--paper);
}

.cylinder-wrap {
  --view-progress: 0;
  position: relative;
  align-self: center;
  grid-column: 2 / 4;
  grid-row: 1 / 3;
  justify-self: center;
  width: min(68vw, 58rem);
  height: min(58vw, 39rem);
  perspective: 1400px;
}

.cylinder-scene {
  position: absolute;
  top: 48%;
  left: 50%;
  width: min(27vw, 20rem);
  height: min(34vw, 25rem);
  transform: translate(-50%, -50%);
  transform-style: preserve-3d;
}

.cylinder {
  position: absolute;
  inset: 0;
  border-right: 1px solid rgba(27, 26, 24, 0.34);
  border-left: 1px solid rgba(27, 26, 24, 0.34);
  transform: rotateX(calc(var(--view-progress) * 78deg)) rotateY(calc(-8deg + var(--view-progress) * 8deg));
  transform-style: preserve-3d;
  transition: transform 180ms ease-out;
}

.cylinder::before {
  position: absolute;
  inset: 0;
  opacity: 0.35;
  background: repeating-linear-gradient(90deg, transparent 0 9%, rgba(27, 26, 24, 0.14) 9.2%, transparent 9.5%);
  content: "";
}

.cylinder-ring {
  position: absolute;
  left: -1px;
  width: calc(100% + 2px);
  height: 24%;
  border: 1px solid rgba(27, 26, 24, 0.48);
  border-radius: 50%;
  transform: translateY(-50%) rotateX(72deg);
}

.ring-top { top: 0; }
.ring-bottom { top: 100%; }

.cylinder-axis {
  position: absolute;
  top: -8%;
  left: 50%;
  width: 1px;
  height: 116%;
  background: rgba(168, 72, 44, 0.56);
  transform: translateX(-50%);
}

.cylinder-meridian {
  position: absolute;
  top: 0;
  bottom: 0;
  width: 30%;
  border-radius: 50%;
  opacity: 0.3;
}

.meridian-a {
  left: 15%;
  border-right: 1px solid var(--ink);
}

.meridian-b {
  right: 15%;
  border-left: 1px solid var(--ink);
}

.projection-ray {
  position: absolute;
  top: 50%;
  left: 50%;
  z-index: -1;
  width: min(44vw, 33rem);
  height: 1px;
  background: linear-gradient(90deg, rgba(27, 26, 24, 0.18), transparent);
  transform-origin: left;
  transition: transform 240ms ease, opacity 240ms ease;
}

.ray-1 { transform: rotate(calc(-18deg + var(--view-progress) * 11deg)) translateZ(-2rem); }
.ray-2 { transform: rotate(calc(2deg - var(--view-progress) * 2deg)) translateZ(1rem); }
.ray-3 { transform: rotate(calc(22deg - var(--view-progress) * 15deg)) translateZ(3rem); }

.view-readout {
  position: absolute;
  top: 0;
  right: 0;
  display: grid;
  grid-template-columns: auto auto auto auto;
  align-items: center;
  gap: 0.85rem;
  min-width: 18rem;
  padding-bottom: 0.8rem;
  border-bottom: 1px solid rgba(27, 26, 24, 0.22);
  font-size: 0.67rem;
}

.view-readout span {
  opacity: 0.48;
  letter-spacing: 0.08em;
}

.view-readout strong,
.view-readout em {
  font-family: "Songti SC", "STSong", serif;
  font-size: 1rem;
  font-style: normal;
  font-weight: 400;
}

.view-readout i {
  width: 2.4rem;
  height: 1px;
  overflow: hidden;
  background: rgba(27, 26, 24, 0.2);
}

.view-readout i::after {
  display: block;
  width: 100%;
  height: 100%;
  background: var(--ember);
  content: "";
  transform: scaleX(var(--view-progress));
  transform-origin: left;
}

.view-readout em {
  color: var(--ember);
}

.projection-plane {
  position: absolute;
  top: 50%;
  display: grid;
  place-items: center;
  width: clamp(8rem, 13vw, 11rem);
  aspect-ratio: 1;
  border: 1px solid rgba(27, 26, 24, 0.12);
  transform: translateY(-50%);
  transition: opacity 260ms ease, transform 500ms var(--ease-out);
}

.projection-plane span {
  position: absolute;
  top: 0.65rem;
  left: 0.75rem;
  opacity: 0.46;
  font-size: 0.58rem;
  letter-spacing: 0.1em;
}

.projection-plane b {
  position: absolute;
  right: 0.65rem;
  bottom: 0.55rem;
  font-family: "Songti SC", "STSong", serif;
  font-size: 0.8rem;
  font-weight: 400;
}

.plane-front {
  left: 0;
  opacity: calc(1 - var(--view-progress) * 0.7);
}

.plane-top {
  right: 0;
  opacity: calc(0.3 + var(--view-progress) * 0.7);
}

.projection-shape {
  border: 1px solid currentColor;
  transition: border-color 300ms ease, transform 500ms var(--ease-out);
}

.shape-rect {
  width: 44%;
  height: 63%;
  transform: scale(calc(1 - var(--view-progress) * 0.25));
}

.shape-circle {
  width: 56%;
  aspect-ratio: 1;
  border-radius: 50%;
  color: var(--ember);
  transform: scale(calc(0.72 + var(--view-progress) * 0.28));
}

.view-control {
  position: absolute;
  right: 12%;
  bottom: 1.7rem;
  left: 12%;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 1rem;
}

.view-option {
  min-width: 3.6rem;
  min-height: 2.75rem;
  padding: 0.55rem 0.7rem;
  border: 0;
  background: transparent;
  opacity: 0.38;
  cursor: pointer;
  font-family: "Songti SC", "STSong", serif;
  font-size: 0.75rem;
  transition: opacity 260ms ease, color 260ms ease;
}

.view-option.is-active {
  color: var(--ember);
  opacity: 1;
}

.view-range {
  width: 100%;
  height: 2.75rem;
  margin: 0;
  appearance: none;
  background: transparent;
  cursor: grab;
}

.view-range:active {
  cursor: grabbing;
}

.view-range:focus-visible,
.moderation-range:focus-visible {
  outline: none;
}

.view-range::-webkit-slider-runnable-track {
  height: 1px;
  background: linear-gradient(90deg, var(--ember) calc(var(--view-progress) * 100%), rgba(27, 26, 24, 0.2) 0);
}

.view-range::-webkit-slider-thumb {
  width: 1rem;
  height: 1rem;
  margin-top: -0.48rem;
  appearance: none;
  border: 1px solid var(--ember);
  border-radius: 50%;
  background: var(--paper);
  box-shadow: 0 0 0 0.35rem rgba(168, 72, 44, 0.08);
}

.view-range:focus-visible::-webkit-slider-thumb,
.moderation-range:focus-visible::-webkit-slider-thumb {
  box-shadow: 0 0 0 0.42rem rgba(168, 72, 44, 0.14);
}

.view-range::-moz-range-track {
  height: 1px;
  background: rgba(27, 26, 24, 0.2);
}

.view-range::-moz-range-progress {
  height: 1px;
  background: var(--ember);
}

.view-range::-moz-range-thumb {
  width: 1rem;
  height: 1rem;
  border: 1px solid var(--ember);
  border-radius: 50%;
  background: var(--paper);
}

.view-range:focus-visible::-moz-range-thumb,
.moderation-range:focus-visible::-moz-range-thumb {
  box-shadow: 0 0 0 0.42rem rgba(168, 72, 44, 0.14);
}

.cylinder-hint {
  right: 12%;
  bottom: -0.4rem;
}

.interaction-hint {
  position: absolute;
  right: 0;
  bottom: 0;
  display: flex;
  align-items: center;
  gap: 0.65rem;
  margin: 0;
  opacity: 0.45;
  font-size: 0.62rem;
  letter-spacing: 0.1em;
}

.interaction-hint span {
  display: block;
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--ember);
}

.chapter-theory {
  background:
    radial-gradient(circle at 52% 76%, rgba(155, 70, 42, 0.12), transparent 26%),
    var(--night-2);
}

.chapter-theory .chapter-statement p {
  max-width: 13ch;
  font-size: clamp(1.75rem, 3.2vw, 3.5rem);
  line-height: 1.14;
}

.theory-canvas,
.theory-vignette {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.theory-canvas {
  opacity: 0.8;
}

.theory-vignette {
  background: radial-gradient(circle at 50% 68%, transparent 0%, rgba(15, 15, 14, 0.18) 45%, rgba(15, 15, 14, 0.8) 100%);
}

.theory-label {
  position: absolute;
  z-index: 2;
  right: 10%;
  bottom: 21%;
  display: flex;
  align-items: center;
  gap: 0.8rem;
  opacity: 0.42;
  font-family: "Songti SC", "STSong", serif;
  font-size: 0.67rem;
}

.theory-label i {
  width: 4.5rem;
  height: 1px;
  background: linear-gradient(90deg, var(--ember), currentColor);
}

.chapter-moderation {
  background:
    radial-gradient(circle at 61% 48%, rgba(168, 72, 44, 0.07), transparent 27%),
    var(--paper);
}

.moderation-stage {
  --balance: 0.18;
  --tilt: -5.1deg;
  position: relative;
  align-self: center;
  grid-column: 2 / 4;
  grid-row: 2;
  justify-self: center;
  width: min(68vw, 54rem);
  min-height: 22rem;
}

.moderation-readout {
  position: absolute;
  top: 0;
  right: 0;
  left: 0;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  padding-bottom: 0.8rem;
  border-bottom: 1px solid rgba(27, 26, 24, 0.18);
  font-family: "Songti SC", "STSong", serif;
  font-size: 0.7rem;
}

.moderation-readout span {
  opacity: 0.38;
}

.moderation-readout span:last-child {
  text-align: right;
}

.moderation-readout strong {
  color: var(--ember);
  font-size: 1rem;
  font-weight: 400;
  transition: transform 400ms var(--ease-out);
}

.moderation-object {
  position: absolute;
  top: 46%;
  left: 50%;
  width: min(74%, 37rem);
  height: 9rem;
  transform: translate(-50%, -50%);
}

.moderation-object::before {
  position: absolute;
  top: 50%;
  left: 0;
  width: 100%;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--ink) 9%, var(--ink) 91%, transparent);
  content: "";
  transform: rotate(var(--tilt));
  transition: transform 420ms var(--ease-out), background 420ms ease;
}

.moderation-object i {
  position: absolute;
  top: 50%;
  left: calc(var(--balance) * 100%);
  width: 0.8rem;
  height: 0.8rem;
  border: 1px solid var(--ember);
  border-radius: 50%;
  background: var(--paper);
  box-shadow: 0 0 0 0.55rem rgba(168, 72, 44, 0.08);
  transform: translate(-50%, -50%);
  transition: left 220ms ease-out, background 300ms ease;
}

.moderation-object span {
  position: absolute;
  top: 50%;
  left: 50%;
  color: var(--ember);
  opacity: 0.2;
  font-family: "Songti SC", "STSong", serif;
  font-size: clamp(3rem, 7vw, 7rem);
  transform: translate(-50%, -50%);
  transition: opacity 420ms ease, transform 500ms var(--ease-out);
}

.moderation-stage[data-state="middle"] .moderation-object::before {
  background: linear-gradient(90deg, transparent, var(--ember) 9%, var(--ember) 91%, transparent);
}

.moderation-stage[data-state="middle"] .moderation-object i {
  background: var(--ember);
}

.moderation-stage[data-state="middle"] .moderation-object span {
  opacity: 1;
  transform: translate(-50%, -50%) scale(1.04);
}

.moderation-control {
  position: absolute;
  right: 9%;
  bottom: 2.5rem;
  left: 9%;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 1rem;
  font-family: "Songti SC", "STSong", serif;
  font-size: 0.68rem;
}

.moderation-control span {
  opacity: 0.42;
}

.moderation-range {
  width: 100%;
  height: 2.75rem;
  margin: 0;
  appearance: none;
  background: transparent;
  cursor: grab;
  touch-action: pan-x;
}

.moderation-range:active {
  cursor: grabbing;
}

.moderation-range::-webkit-slider-runnable-track {
  height: 1px;
  background: linear-gradient(90deg, rgba(27, 26, 24, 0.18) 0 47%, var(--ember) 47% 53%, rgba(27, 26, 24, 0.18) 53%);
}

.moderation-range::-webkit-slider-thumb {
  width: 1rem;
  height: 1rem;
  margin-top: -0.48rem;
  appearance: none;
  border: 1px solid var(--ember);
  border-radius: 50%;
  background: var(--paper);
}

.moderation-range::-moz-range-track {
  height: 1px;
  background: rgba(27, 26, 24, 0.18);
}

.moderation-range::-moz-range-thumb {
  width: 1rem;
  height: 1rem;
  border: 1px solid var(--ember);
  border-radius: 50%;
  background: var(--paper);
}

.moderation-hint {
  right: 0;
  bottom: 0;
}

.chapter-dissolve {
  min-height: 130svh;
  padding-bottom: 0;
  background: var(--night);
}

.dissolve-image {
  position: absolute;
  inset: 0;
  opacity: calc(0.07 + var(--section-progress, 0) * 0.16);
  background:
    linear-gradient(0deg, var(--night) 0%, transparent 48%, rgba(25, 24, 22, 0.25) 100%),
    url("../assets/ember-tree.png") 70% 50% / cover;
  filter: grayscale(0.75) contrast(1.08);
  transform: scale(calc(1.08 - var(--section-progress, 0) * 0.035));
}

.dissolve-field {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, var(--night) 0%, transparent 44%, rgba(25, 24, 22, 0.3) 100%),
    linear-gradient(0deg, var(--night) 0%, transparent 43%);
}

.dissolve-stage {
  position: relative;
  align-self: center;
  grid-column: 2 / 4;
  grid-row: 2;
  height: 14rem;
}

.horizon-word {
  position: absolute;
  top: 50%;
  font-family: "Songti SC", "STSong", serif;
  transform: translateY(-50%);
}

.horizon-word {
  right: 3%;
  color: var(--ember-bright);
  opacity: calc(0.1 + var(--section-progress, 0) * 0.9);
  font-size: clamp(1.2rem, 2.2vw, 2.2rem);
  letter-spacing: 0.28em;
}

.direction-line {
  position: absolute;
  top: 50%;
  right: 12%;
  left: 26%;
  height: 1px;
  overflow: hidden;
  background: rgba(221, 214, 201, 0.14);
}

.direction-line i {
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, transparent, var(--ember), var(--bone));
  transform: translateX(calc(-100% + var(--section-progress, 0) * 100%));
}

.site-footer {
  position: absolute;
  z-index: 3;
  right: var(--page-pad);
  bottom: 0;
  left: var(--page-pad);
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: end;
  gap: 2rem;
  min-height: 15rem;
  padding: 3rem 0;
  border-top: 1px solid rgba(221, 214, 201, 0.16);
}

.footer-mark {
  margin: 0;
  font-family: "Times New Roman", serif;
  font-size: 1.7rem;
}

.footer-mark span {
  margin-left: 0.4rem;
  color: var(--ember);
  font-family: "Songti SC", "STSong", serif;
  font-size: 0.8rem;
}

.footer-line,
.footer-year {
  margin: 0;
  opacity: 0.45;
  font-size: 0.67rem;
  letter-spacing: 0.08em;
}

.back-to-top {
  display: flex;
  align-items: center;
  gap: 1rem;
  font-size: 0.68rem;
  letter-spacing: 0.08em;
}

.back-to-top span {
  color: var(--ember);
  font-size: 1rem;
}

.footer-year {
  position: absolute;
  right: 0;
  top: 3rem;
}

.noscript {
  position: fixed;
  z-index: 999;
  right: 1rem;
  bottom: 1rem;
  max-width: 25rem;
  padding: 0.8rem 1rem;
  color: var(--paper);
  background: var(--ink);
  font-size: 0.75rem;
}

@media (max-width: 900px) {
  .site-header {
    grid-template-columns: 1fr auto;
  }

  .chapter-progress {
    display: none;
  }

  .chapter-rail {
    display: none;
  }

  .hero-copy {
    top: 47%;
  }

  .chapter {
    min-height: 100svh;
  }

  .chapter-grid {
    grid-template-columns: 1fr 1fr;
    grid-template-rows: auto minmax(18rem, 1fr) auto;
    min-height: calc(100svh - 12rem);
    gap: 2.2rem 1rem;
  }

  .chapter-heading {
    grid-column: 1 / -1;
  }

  .chapter-statement {
    grid-column: 1 / -1;
    grid-row: 3;
  }

  .restraint-stage,
  .moderation-stage,
  .dissolve-stage {
    grid-column: 1 / -1;
    grid-row: 2;
  }

  .posture-words {
    left: 20%;
    width: 80%;
  }

  .posture-orbit {
    right: -15%;
    width: 70vw;
  }

  .cylinder-wrap {
    grid-column: 1 / -1;
    grid-row: 2;
    width: 100%;
    height: 28rem;
  }

  .cylinder-scene {
    width: 14rem;
    height: 19rem;
  }

  .theory-label {
    display: none;
  }

  .site-footer {
    grid-template-columns: 1fr auto;
  }

}

@media (max-width: 600px) {
  :root {
    --page-pad: 1.35rem;
  }

  .site-header {
    padding-top: 1.05rem;
  }

  .hero-image {
    inset: -3%;
    background-position: 61% center;
  }

  .hero-shade {
    background:
      linear-gradient(90deg, rgba(9, 9, 8, 0.72), rgba(9, 9, 8, 0.25)),
      linear-gradient(0deg, rgba(9, 9, 8, 0.92), transparent 67%);
  }

  .hero-copy {
    top: 50%;
  }

  .eyebrow {
    margin-bottom: 1.4rem;
  }

  .title-en {
    font-size: clamp(4rem, 23vw, 7rem);
  }

  .title-cn {
    margin-top: 0.42em;
    font-size: clamp(2rem, 11vw, 3.2rem);
  }

  .scroll-cue {
    bottom: 2rem;
    justify-content: center;
    width: 2.75rem;
    min-height: 2.75rem;
  }

  .chapter {
    min-height: max(100svh, 52rem);
    padding-top: 6.5rem;
    padding-bottom: 4rem;
  }

  .chapter-grid {
    grid-template-columns: 1fr;
    grid-template-rows: auto minmax(17rem, 1fr) auto;
    min-height: max(calc(100svh - 10.5rem), 42rem);
    gap: 1.65rem;
  }

  .chapter-index {
    margin-bottom: 1.15rem;
  }

  .chapter-heading h2 {
    max-width: 10em;
    font-size: clamp(2.6rem, 13vw, 3.85rem);
    line-height: 1.08;
  }

  .chapter-statement {
    grid-column: 1;
    grid-row: 3;
  }

  .chapter-statement p {
    font-size: clamp(2rem, 11vw, 3.4rem);
  }

  .chapter-statement.is-small-quote {
    max-width: 100%;
    padding-right: 0.8rem;
  }

  .chapter-statement.is-small-quote p {
    font-size: clamp(0.92rem, 4.1vw, 1.05rem);
    line-height: 1.52;
  }

  .chapter-restraint {
    min-height: max(100svh, 58rem);
  }

  .chapter-restraint .chapter-grid {
    grid-template-rows: auto minmax(23rem, 1fr) auto;
    min-height: 48rem;
  }

  .restraint-stage {
    height: 23rem;
  }

  .magic-card {
    width: clamp(5.7rem, 25vw, 6.4rem);
  }

  .magic-whisper {
    right: 0;
  }

  .posture-orbit {
    top: 47%;
    right: -30%;
    width: 95vw;
  }

  .posture-words {
    top: 48%;
    left: 0;
    width: 100%;
  }

  .ghost-output {
    font-size: 31vw;
  }

  .cylinder-wrap {
    grid-column: 1;
    width: 100%;
    height: 31rem;
    perspective: 900px;
  }

  .chapter-cylinder {
    min-height: max(100svh, 64rem);
  }

  .chapter-cylinder .chapter-grid {
    min-height: 54rem;
  }

  .view-readout {
    right: 0;
    left: 0;
    grid-template-columns: 1fr auto 2rem auto;
    min-width: 0;
    min-height: 2.75rem;
  }

  .cylinder-scene {
    top: 48%;
    width: 8.7rem;
    height: 12.8rem;
  }

  .projection-ray {
    width: 11.5rem;
  }

  .projection-plane {
    top: 45%;
    width: 6.3rem;
  }

  .projection-plane span {
    top: 0.4rem;
    left: 0.5rem;
  }

  .projection-plane b {
    right: 0.45rem;
    bottom: 0.35rem;
  }

  .view-control {
    right: 0;
    bottom: 2.8rem;
    left: 0;
    gap: 0.45rem;
  }

  .view-option {
    min-width: 3.4rem;
    min-height: 3rem;
  }

  .view-range {
    height: 3rem;
    touch-action: pan-x;
  }

  .cylinder-hint {
    right: auto;
    bottom: 0;
    left: 0;
    max-width: 18rem;
  }

  .moderation-stage {
    width: 100%;
    min-height: 25rem;
  }

  .chapter-moderation {
    min-height: max(100svh, 58rem);
  }

  .chapter-moderation .chapter-grid {
    grid-template-rows: auto minmax(25rem, 1fr) auto;
    min-height: 49rem;
  }

  .moderation-object {
    top: 45%;
    width: 92%;
  }

  .moderation-object span {
    font-size: 21vw;
  }

  .moderation-control {
    right: 0;
    bottom: 2.8rem;
    left: 0;
    min-height: 3rem;
  }

  .moderation-range {
    height: 3rem;
  }

  .moderation-hint {
    right: auto;
    left: 0;
  }

  .dissolve-stage {
    width: 100%;
  }

  .chapter-dissolve {
    min-height: max(130svh, 65rem);
  }

  .chapter-dissolve .chapter-grid {
    min-height: 54rem;
    padding-bottom: 11rem;
  }

  .horizon-word {
    font-size: 1rem;
  }

  .site-footer {
    right: var(--page-pad);
    left: var(--page-pad);
    grid-template-columns: 1fr auto;
    min-height: 12rem;
  }

  .back-to-top {
    justify-content: flex-end;
    min-height: 2.75rem;
  }

  .footer-year {
    display: none;
  }
}

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

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

  .reveal,
  .word-reveal {
    opacity: 1;
    clip-path: none;
    transform: none;
  }
}