:root {
  --ink: #17313a;
  --ink-soft: #50666c;
  --paper: #f4f1e8;
  --paper-deep: #e8e7dc;
  --white: #fffef9;
  --night: #13272f;
  --night-2: #193740;
  --lime: #cbe36b;
  --teal: #2d7d77;
  --teal-light: #89cec4;
  --orange: #ef9e68;
  --violet: #c6b5eb;
  --line: rgba(23, 49, 58, 0.17);
  --shadow: 0 28px 80px rgba(24, 45, 51, 0.12);
  --serif: Georgia, "Times New Roman", "Noto Serif SC", serif;
  --sans: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 90px;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.72;
  overflow-x: hidden;
}

button,
input {
  font: inherit;
}

button,
a {
  -webkit-tap-highlight-color: transparent;
}

a {
  color: inherit;
}

button:focus-visible,
a:focus-visible,
input:focus-visible,
summary:focus-visible {
  outline: 3px solid var(--orange);
  outline-offset: 4px;
}

.reading-progress {
  position: fixed;
  inset: 0 0 auto;
  z-index: 100;
  height: 3px;
  background: transparent;
}

.reading-progress span {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--orange), var(--lime));
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 90;
  display: grid;
  grid-template-columns: minmax(220px, 1fr) auto minmax(220px, 1fr);
  align-items: center;
  gap: 24px;
  min-height: 72px;
  padding: 10px clamp(20px, 4vw, 70px);
  color: #eaf1e9;
  background: rgba(19, 39, 47, 0.95);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  width: fit-content;
  color: #eaf1e9;
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  color: var(--night);
  background: var(--lime);
  border-radius: 50%;
  font-family: var(--serif);
  font-size: 13px;
  letter-spacing: 0;
}

.topbar nav {
  display: flex;
  align-items: center;
  gap: 22px;
}

.topbar nav a {
  color: #b9c9c7;
  font-size: 12px;
  font-weight: 700;
  text-decoration: none;
}

.topbar nav a:hover {
  color: var(--lime);
}

.topbar-actions {
  display: flex;
  justify-content: flex-end;
  gap: 8px;
}

.paper-link {
  padding: 8px 13px;
  color: var(--night);
  background: var(--lime);
  border: 1px solid var(--lime);
  border-radius: 999px;
  font-size: 11px;
  font-weight: 900;
  text-decoration: none;
}

.paper-link.secondary {
  color: #eaf1e9;
  background: transparent;
  border-color: rgba(255, 255, 255, 0.22);
}

.hero {
  position: relative;
  color: #edf4ed;
  background:
    radial-gradient(circle at 75% 30%, rgba(45, 125, 119, 0.4), transparent 32%),
    radial-gradient(circle at 15% 80%, rgba(239, 158, 104, 0.13), transparent 28%),
    var(--night);
  overflow: hidden;
}

.hero::after {
  position: absolute;
  right: -8vw;
  bottom: -28vw;
  width: 52vw;
  height: 52vw;
  border: 1px solid rgba(203, 227, 107, 0.12);
  border-radius: 50%;
  content: "";
}

.hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(480px, 0.98fr);
  align-items: center;
  gap: clamp(30px, 5vw, 80px);
  width: min(1500px, calc(100% - 72px));
  min-height: min(790px, calc(100vh - 72px));
  margin: 0 auto;
  padding: 80px 0 64px;
}

.eyebrow,
.kicker,
.section-marker p,
.stage-note {
  margin: 0;
  font-size: 11px;
  font-weight: 900;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.eyebrow {
  color: var(--teal-light);
}

.hero h1 {
  max-width: 760px;
  margin: 22px 0 24px;
  font-family: var(--serif);
  font-size: clamp(50px, 6.1vw, 94px);
  font-weight: 400;
  line-height: 0.98;
  letter-spacing: -0.045em;
}

.hero h1 em {
  color: var(--lime);
  font-style: italic;
}

.hero h1 span {
  display: block;
  max-width: 650px;
  margin-top: 28px;
  color: #bbcbc9;
  font-family: var(--sans);
  font-size: clamp(17px, 1.5vw, 22px);
  font-weight: 500;
  line-height: 1.55;
  letter-spacing: 0;
}

.hero-deck {
  max-width: 710px;
  margin: 0;
  color: #b8c8c6;
  font-size: clamp(17px, 1.25vw, 20px);
}

.hero-deck strong {
  color: #fff;
}

.hero-actions {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 36px;
}

.hero-actions a {
  display: inline-flex;
  align-items: center;
  min-height: 48px;
  padding: 0 20px;
  border-radius: 4px;
  font-size: 13px;
  font-weight: 900;
  text-decoration: none;
}

.primary-button {
  color: var(--night);
  background: var(--lime);
}

.ghost-button {
  color: #eef4ee;
  border: 1px solid rgba(255, 255, 255, 0.28);
}

.hero-actions > span {
  color: #809491;
  font-size: 12px;
}

.hero-stage {
  position: relative;
  max-width: 720px;
  padding: 26px;
  background: rgba(8, 21, 26, 0.42);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 22px;
  box-shadow: 0 40px 100px rgba(0, 0, 0, 0.25);
}

.hero-stage svg {
  display: block;
  width: 100%;
}

.stage-note {
  margin-top: 12px;
  color: #68807e;
  text-align: center;
  font-size: 8px;
}

.hero-metrics {
  position: relative;
  z-index: 2;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  width: min(1500px, calc(100% - 72px));
  margin: 0 auto;
  border-top: 1px solid rgba(255, 255, 255, 0.11);
}

.hero-metrics div {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 24px clamp(10px, 2vw, 30px);
  border-right: 1px solid rgba(255, 255, 255, 0.11);
}

.hero-metrics div:last-child {
  border-right: 0;
}

.hero-metrics strong {
  color: var(--lime);
  font-family: var(--serif);
  font-size: 32px;
  font-weight: 400;
}

.hero-metrics span {
  color: #98aaa8;
  font-size: 12px;
}

.chapter {
  position: relative;
  padding: clamp(90px, 10vw, 160px) max(28px, calc((100vw - 1380px) / 2));
  background: var(--paper);
}

.chapter.tint {
  background: var(--paper-deep);
}

.chapter.dark {
  color: #ecf2eb;
  background: var(--night);
}

.section-marker {
  display: grid;
  grid-template-columns: 54px auto;
  align-items: center;
  gap: 18px;
  margin-bottom: 58px;
  color: var(--teal);
}

.dark .section-marker {
  color: var(--teal-light);
}

.section-marker span {
  display: grid;
  place-items: center;
  width: 54px;
  height: 32px;
  color: var(--paper);
  background: var(--teal);
  border-radius: 999px;
  font-family: var(--serif);
  font-size: 14px;
}

.dark .section-marker span {
  color: var(--night);
  background: var(--lime);
}

.chapter-copy {
  display: grid;
  grid-template-columns: minmax(0, 1.08fr) minmax(310px, 0.62fr);
  column-gap: clamp(40px, 8vw, 140px);
  align-items: end;
  max-width: 1280px;
  margin-bottom: clamp(50px, 7vw, 95px);
}

.chapter-copy .kicker {
  grid-column: 1 / -1;
  margin-bottom: 12px;
  color: var(--teal);
}

.dark .chapter-copy .kicker {
  color: var(--teal-light);
}

.chapter h2 {
  margin: 0;
  font-family: var(--serif);
  font-size: clamp(38px, 5.1vw, 72px);
  font-weight: 400;
  line-height: 1.06;
  letter-spacing: -0.035em;
}

.chapter-copy .lead {
  margin: 0;
  color: var(--ink-soft);
  font-size: 17px;
}

.dark .chapter-copy .lead {
  color: #a9bab8;
}

.master-chain {
  display: grid;
  grid-template-columns: 1fr auto 1fr auto 1fr auto 1fr auto 1.15fr;
  align-items: stretch;
  gap: 10px;
}

.chain-node {
  display: flex;
  flex-direction: column;
  min-width: 0;
  padding: 22px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 10px;
}

.chain-node.accent {
  background: #e8f0c8;
  border-color: rgba(117, 141, 33, 0.35);
}

.chain-node.dark {
  color: #f5f8f2;
  background: var(--night);
}

.chain-node span {
  color: var(--teal);
  font-size: 11px;
  font-weight: 900;
  letter-spacing: 0.1em;
}

.chain-node.dark span {
  color: var(--lime);
}

.chain-node strong {
  margin: 18px 0 22px;
  font-family: var(--serif);
  font-size: clamp(17px, 1.45vw, 24px);
  font-weight: 400;
  line-height: 1.35;
}

.chain-node small {
  margin-top: auto;
  color: #738589;
  font-size: 11px;
  line-height: 1.5;
}

.master-chain > i {
  align-self: center;
  color: var(--orange);
  font-family: var(--serif);
  font-size: 24px;
  font-style: normal;
}

.reading-rule,
.warning,
.metric-note,
.flow-note {
  display: grid;
  grid-template-columns: 190px 1fr;
  gap: 28px;
  max-width: 1000px;
  margin: 48px 0 0 auto;
  padding: 26px 30px;
  background: rgba(255, 255, 255, 0.48);
  border-left: 4px solid var(--orange);
}

.reading-rule strong,
.warning strong,
.metric-note strong,
.flow-note strong {
  font-size: 12px;
  letter-spacing: 0.06em;
}

.reading-rule p,
.warning p,
.metric-note p,
.flow-note p {
  margin: 0;
  color: var(--ink-soft);
}

.cg-lab,
.noise-lab,
.landscape-lab,
.mode-lab,
.results-lab {
  display: grid;
  grid-template-columns: minmax(300px, 0.72fr) minmax(0, 1.28fr);
  min-height: 390px;
  margin: 0 0 52px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 14px;
  box-shadow: var(--shadow);
  overflow: hidden;
}

.cg-copy,
.noise-copy,
.landscape-control,
.results-controls {
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: clamp(28px, 4vw, 58px);
}

.cg-copy .kicker,
.noise-copy .kicker,
.landscape-control .kicker,
.results-controls .kicker {
  color: var(--teal);
}

.cg-copy h3,
.noise-copy h3,
.results-controls h3 {
  margin: 10px 0 12px;
  font-family: var(--serif);
  font-size: clamp(28px, 3vw, 45px);
  font-weight: 400;
  line-height: 1.12;
}

.cg-copy p,
.noise-copy p,
.landscape-control p,
.results-controls p {
  color: var(--ink-soft);
}

input[type="range"] {
  width: 100%;
  height: 5px;
  margin: 24px 0 5px;
  accent-color: var(--teal);
  cursor: pointer;
}

.cg-stage,
.noise-stage,
.landscape-visual {
  display: grid;
  place-items: center;
  min-height: 350px;
  padding: 25px;
  background: var(--night);
}

.cg-stage svg,
.noise-stage svg,
.landscape-visual svg,
.mode-visual svg {
  width: 100%;
  max-height: 390px;
}

.cg-stage .backbone {
  fill: none;
  stroke: rgba(203, 227, 107, 0.36);
  stroke-width: 5;
}

.atom-dot {
  fill: #e0e8df;
  opacity: 0.78;
}

.bead-dot {
  fill: var(--orange);
  stroke: #fff;
  stroke-width: 3;
}

.formula-card {
  position: relative;
  max-width: 1220px;
  margin: 54px auto 0;
  padding: clamp(30px, 5vw, 70px);
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 14px;
  box-shadow: var(--shadow);
}

.formula-card.central {
  color: #eff5ee;
  background: var(--night);
}

.formula-head {
  display: grid;
  grid-template-columns: 180px minmax(220px, 0.8fr) minmax(260px, 1fr);
  gap: 24px;
  align-items: baseline;
  margin-bottom: 48px;
}

.formula-head span {
  color: var(--teal);
  font-size: 11px;
  font-weight: 900;
  letter-spacing: 0.12em;
}

.central .formula-head span {
  color: var(--lime);
}

.formula-head h3 {
  margin: 0;
  font-family: var(--serif);
  font-size: clamp(27px, 3vw, 42px);
  font-weight: 400;
  line-height: 1.15;
}

.formula-head p {
  margin: 0;
  color: var(--ink-soft);
}

.central .formula-head p {
  color: #aabbb9;
}

.equation {
  display: block;
  max-width: 100%;
  padding: 20px 10px;
  color: var(--ink);
  font-family: var(--serif);
  font-size: clamp(22px, 2.5vw, 37px);
  line-height: 1.5;
  text-align: center;
  overflow-x: auto;
  scrollbar-width: thin;
}

.central .equation,
.dark .equation {
  color: #f3f6f0;
}

.equation.secondary {
  margin-top: 10px;
  color: var(--teal);
  background: rgba(45, 125, 119, 0.07);
  border-radius: 8px;
}

.equation.hero-equation {
  padding: 42px 18px;
  font-size: clamp(27px, 4.2vw, 58px);
  white-space: nowrap;
}

.equation.small {
  padding: 16px 0;
  font-size: clamp(19px, 2vw, 27px);
  text-align: left;
}

.equation em {
  color: var(--orange);
  font-style: normal;
}

.fraction {
  display: inline-flex;
  flex-direction: column;
  vertical-align: middle;
  line-height: 1.25;
}

.fraction > span:first-child {
  padding: 0 8px 5px;
  border-bottom: 1.5px solid currentColor;
}

.fraction > span:last-child {
  padding: 5px 8px 0;
}

.symbol-grid,
.assumption-row,
.term-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  margin-top: 44px;
  border-top: 1px solid var(--line);
}

.symbol-grid div,
.assumption-row span,
.term-grid div {
  padding: 20px;
  border-right: 1px solid var(--line);
}

.symbol-grid div:last-child,
.assumption-row span:last-child,
.term-grid div:last-child {
  border-right: 0;
}

.symbol-grid b,
.term-grid b {
  display: block;
  margin-bottom: 5px;
  color: var(--teal);
  font-family: var(--serif);
  font-size: 21px;
  font-weight: 400;
}

.symbol-grid span,
.assumption-row span,
.term-grid span,
.term-grid p {
  color: var(--ink-soft);
  font-size: 12px;
}

.central .assumption-row {
  border-color: rgba(255, 255, 255, 0.15);
}

.central .assumption-row span {
  color: #acbdbb;
  border-color: rgba(255, 255, 255, 0.15);
}

.central .assumption-row b {
  color: var(--lime);
}

.term-grid .accent {
  background: #e8f0c8;
}

.formula-caption {
  max-width: 820px;
  margin: 32px auto 0;
  color: var(--ink-soft);
  text-align: center;
}

.derivation {
  margin-top: 36px;
  border-top: 1px solid var(--line);
}

.central .derivation {
  border-color: rgba(255, 255, 255, 0.17);
}

.derivation summary {
  padding: 24px 4px;
  color: var(--teal);
  font-size: 13px;
  font-weight: 900;
  cursor: pointer;
}

.central .derivation summary {
  color: var(--lime);
}

.derivation-body {
  max-width: 940px;
  margin: 0 auto;
  padding: 15px 0 20px;
}

.derivation-body p {
  margin: 28px 0 4px;
  color: var(--ink-soft);
}

.central .derivation-body p {
  color: #b0c0be;
}

.derivation-body.numbered > p > b {
  display: inline-grid;
  place-items: center;
  width: 28px;
  height: 28px;
  margin-right: 8px;
  color: var(--night);
  background: var(--lime);
  border-radius: 50%;
}

.landscape-lab {
  grid-template-columns: minmax(0, 1.35fr) minmax(300px, 0.65fr);
  background: var(--night-2);
  border-color: rgba(255, 255, 255, 0.11);
}

.landscape-control {
  color: #eff4ed;
}

.landscape-control .kicker {
  color: var(--teal-light);
}

.landscape-control p {
  color: #a8b9b7;
}

.live-values {
  display: grid;
  gap: 1px;
  margin: 25px 0;
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.live-values div {
  display: flex;
  justify-content: space-between;
  gap: 15px;
  padding: 12px 15px;
  background: var(--night-2);
}

.live-values span {
  color: #8fa3a1;
  font-size: 12px;
}

.live-values strong {
  color: var(--lime);
  font-size: 13px;
}

.concept-grid,
.evidence-grid,
.claim-grid,
.source-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  margin-top: 64px;
  background: var(--line);
  border: 1px solid var(--line);
}

.concept-grid article,
.evidence-grid article,
.claim-grid article {
  padding: clamp(28px, 4vw, 52px);
  background: var(--white);
}

.dark .concept-grid {
  background: rgba(255, 255, 255, 0.12);
  border-color: rgba(255, 255, 255, 0.12);
}

.dark .concept-grid article {
  background: var(--night-2);
}

.concept-grid span,
.evidence-grid span,
.claim-grid span {
  color: var(--teal);
  font-size: 10px;
  font-weight: 900;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.dark .concept-grid span {
  color: var(--lime);
}

.concept-grid h3,
.evidence-grid h3,
.claim-grid h3 {
  margin: 15px 0 12px;
  font-family: var(--serif);
  font-size: clamp(22px, 2.2vw, 31px);
  font-weight: 400;
  line-height: 1.2;
}

.concept-grid p,
.evidence-grid p,
.claim-grid p {
  margin: 0;
  color: var(--ink-soft);
}

.dark .concept-grid p {
  color: #a8b9b7;
}

.two-clocks {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: stretch;
  max-width: 1000px;
  margin: 0 auto 58px;
}

.two-clocks div {
  padding: 35px;
  background: var(--white);
  border: 1px solid var(--line);
}

.two-clocks > i {
  align-self: center;
  z-index: 1;
  display: grid;
  place-items: center;
  width: 58px;
  height: 58px;
  margin: 0 -7px;
  color: #fff;
  background: var(--orange);
  border-radius: 50%;
  font-family: var(--serif);
  font-size: 25px;
  font-style: normal;
}

.two-clocks span {
  color: var(--teal);
  font-size: 11px;
  font-weight: 900;
  letter-spacing: 0.1em;
}

.two-clocks strong {
  display: block;
  margin: 14px 0;
  font-family: var(--serif);
  font-size: 26px;
  font-weight: 400;
}

.two-clocks p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 14px;
}

.noise-stage .clean-chain,
.noise-stage .noisy-chain {
  fill: none;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.noise-stage .clean-chain {
  stroke: rgba(137, 206, 196, 0.3);
  stroke-width: 10;
}

.noise-stage .noisy-chain {
  stroke: var(--orange);
  stroke-width: 9;
}

.noise-stage text {
  fill: #9db0ae;
  font-family: var(--serif);
  font-size: 20px;
}

.noise-dot {
  fill: var(--lime);
  opacity: 0.65;
}

.formula-walk {
  display: grid;
  grid-template-columns: minmax(230px, 0.34fr) minmax(0, 1fr);
  max-width: 1200px;
  min-height: 570px;
  margin: 0 auto;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 14px;
  box-shadow: var(--shadow);
  overflow: hidden;
}

.formula-steps {
  display: grid;
  background: var(--night);
}

.formula-step {
  display: grid;
  grid-template-columns: 42px 1fr;
  grid-template-rows: auto auto;
  gap: 0 12px;
  padding: 18px 22px;
  color: #8fa4a2;
  text-align: left;
  background: transparent;
  border: 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.09);
  cursor: pointer;
}

.formula-step span {
  grid-row: 1 / 3;
  color: #607774;
  font-family: var(--serif);
  font-size: 22px;
}

.formula-step strong {
  color: #c5d0cf;
  font-size: 13px;
}

.formula-step small {
  font-family: var(--serif);
  font-size: 12px;
}

.formula-step.active {
  color: #dfe9e5;
  background: var(--teal);
}

.formula-step.active span,
.formula-step.active strong {
  color: var(--lime);
}

.formula-display {
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: clamp(32px, 6vw, 80px);
}

.formula-count {
  color: var(--teal);
  font-size: 10px;
  font-weight: 900;
  letter-spacing: 0.13em;
}

.formula-display h3 {
  max-width: 760px;
  margin: 16px 0 20px;
  font-family: var(--serif);
  font-size: clamp(27px, 3.6vw, 49px);
  font-weight: 400;
  line-height: 1.13;
}

.formula-display > p {
  color: var(--ink-soft);
}

.formula-display aside {
  margin-top: 22px;
  padding: 18px 20px;
  color: var(--ink-soft);
  background: #eef1df;
  border-left: 3px solid var(--lime);
  font-size: 13px;
}

.warning {
  margin-top: 40px;
  background: #f4dfcf;
}

.mode-lab {
  display: block;
  color: var(--ink);
  background: #f6f3ea;
}

.mode-tabs {
  display: grid;
  grid-template-columns: 1fr 1fr;
}

.mode-tab {
  padding: 20px;
  color: #607579;
  background: #e1e5dc;
  border: 0;
  border-bottom: 1px solid var(--line);
  cursor: pointer;
  font-size: 12px;
  font-weight: 900;
  letter-spacing: 0.08em;
}

.mode-tab.active {
  color: var(--night);
  background: var(--lime);
}

.mode-display {
  display: grid;
  grid-template-columns: minmax(0, 1.22fr) minmax(320px, 0.78fr);
  min-height: 430px;
}

.mode-visual {
  display: grid;
  place-items: center;
  padding: 30px;
  background: var(--night-2);
}

.mode-visual circle {
  fill: none;
  stroke: var(--teal-light);
  stroke-width: 3;
}

.mode-visual text {
  fill: #c1d0ce;
  font-family: var(--sans);
  font-size: 11px;
  text-anchor: middle;
}

.mode-visual .iid-mode > path:not(.protein-path) {
  stroke: var(--lime);
  stroke-width: 3;
}

.mode-visual .protein-path {
  fill: none;
  stroke: var(--orange);
  stroke-linecap: round;
  stroke-width: 12;
}

.energy-line {
  fill: none;
  stroke: rgba(203, 227, 107, 0.5);
  stroke-width: 4;
}

.trajectory-dot {
  fill: var(--orange);
}

.mode-copy {
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: clamp(32px, 5vw, 64px);
}

.mode-copy > span {
  color: var(--teal);
  font-size: 10px;
  font-weight: 900;
  letter-spacing: 0.12em;
}

.mode-copy h3 {
  margin: 12px 0;
  font-family: var(--serif);
  font-size: 38px;
  font-weight: 400;
  line-height: 1.12;
}

.mode-copy p,
.mode-copy li {
  color: var(--ink-soft);
}

.mode-copy ul {
  margin: 14px 0 0;
  padding-left: 20px;
}

.time-warning {
  max-width: 960px;
  margin: 60px auto 0;
  padding: clamp(30px, 5vw, 55px);
  color: #f4eee7;
  background: #803f31;
  border-radius: 12px;
}

.time-warning span {
  font-size: 10px;
  font-weight: 900;
  letter-spacing: 0.12em;
}

.time-warning h3 {
  margin: 12px 0;
  font-family: var(--serif);
  font-size: clamp(29px, 3.5vw, 48px);
  font-weight: 400;
  line-height: 1.14;
}

.time-warning p {
  margin: 0;
  color: #ead2c9;
}

.symmetry-board {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.symmetry-board article {
  padding: clamp(30px, 5vw, 58px);
  background: var(--white);
}

.symmetry-board article > span {
  color: var(--orange);
  font-family: var(--serif);
}

.symmetry-board h3 {
  margin: 8px 0;
  font-family: var(--serif);
  font-size: 35px;
  font-weight: 400;
}

.symmetry-board p {
  color: var(--ink-soft);
}

.protein-scale {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 1px;
  margin-bottom: 54px;
  background: var(--line);
  border: 1px solid var(--line);
}

.protein-scale div {
  display: flex;
  flex-direction: column;
  min-height: 180px;
  padding: 24px;
  background: var(--white);
}

.protein-scale span {
  font-size: 11px;
  font-weight: 900;
}

.protein-scale strong {
  margin: auto 0 0;
  color: var(--teal);
  font-family: var(--serif);
  font-size: clamp(35px, 4vw, 59px);
  font-weight: 400;
}

.protein-scale small {
  color: #74868a;
}

.results-lab {
  grid-template-columns: minmax(300px, 0.72fr) minmax(0, 1.28fr);
}

.result-buttons {
  display: grid;
  gap: 6px;
  margin: 20px 0;
}

.result-button {
  padding: 11px 14px;
  color: var(--ink-soft);
  text-align: left;
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 5px;
  cursor: pointer;
  font-size: 12px;
  font-weight: 800;
}

.result-button.active {
  color: #fff;
  background: var(--teal);
  border-color: var(--teal);
}

.result-note {
  min-height: 3.4em;
  font-size: 13px;
}

.results-chart {
  padding: clamp(30px, 5vw, 60px);
  color: #edf3ec;
  background: var(--night);
}

.chart-axis {
  display: flex;
  justify-content: space-between;
  padding-bottom: 8px;
  color: #7f9491;
  border-bottom: 1px solid rgba(255, 255, 255, 0.15);
  font-size: 10px;
}

.bar-rows {
  display: grid;
  gap: 23px;
  margin-top: 22px;
}

.bar-row {
  display: grid;
  grid-template-columns: 90px 1fr;
  gap: 14px;
  align-items: center;
}

.bar-label {
  color: #c1cfcd;
  font-size: 11px;
  font-weight: 800;
}

.bar-pair {
  display: grid;
  gap: 5px;
}

.bar-track {
  position: relative;
  height: 18px;
  background: rgba(255, 255, 255, 0.06);
}

.bar {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  min-width: 2px;
  height: 100%;
  padding-right: 5px;
  color: var(--night);
  font-size: 8px;
  font-weight: 900;
  transition: width 300ms ease;
}

.bar.flow {
  background: var(--violet);
}

.bar.dff {
  background: var(--lime);
}

.bar.na {
  width: 18% !important;
  color: #b1bfbd;
  background: #4d6265;
}

.results-chart > p {
  margin: 26px 0 0;
  color: #809390;
  font-size: 10px;
}

.evidence-grid {
  grid-template-columns: repeat(3, 1fr);
}

.metric-note {
  margin-top: 40px;
  background: #e3e7dd;
}

.claim-grid {
  grid-template-columns: repeat(3, 1fr);
  background: rgba(255, 255, 255, 0.12);
  border-color: rgba(255, 255, 255, 0.12);
}

.claim-grid article {
  background: var(--night-2);
}

.claim-grid article.good {
  background: #245d57;
}

.claim-grid article.next {
  color: var(--night);
  background: var(--lime);
}

.claim-grid span {
  color: var(--lime);
}

.claim-grid .next span {
  color: #48610c;
}

.claim-grid p {
  color: #acbcba;
}

.claim-grid .next p {
  color: #47553e;
}

.after-grid {
  display: grid;
  grid-template-columns: 1fr auto 1fr auto 1fr;
  gap: 22px;
  align-items: center;
}

.after-grid article {
  min-height: 250px;
  padding: 34px;
  background: var(--white);
  border: 1px solid var(--line);
}

.after-grid > i {
  color: var(--orange);
  font-family: var(--serif);
  font-size: 30px;
  font-style: normal;
}

.after-grid span {
  color: var(--teal);
  font-size: 9px;
  font-weight: 900;
  letter-spacing: 0.12em;
}

.after-grid h3 {
  margin: 28px 0 10px;
  font-family: var(--serif);
  font-size: 30px;
  font-weight: 400;
}

.after-grid p {
  color: var(--ink-soft);
}

.flow-note {
  max-width: 1100px;
}

.sources {
  padding-bottom: 100px;
}

.source-grid {
  grid-template-columns: repeat(4, 1fr);
  background: transparent;
  border: 0;
  gap: 12px;
}

.source-card {
  display: flex;
  flex-direction: column;
  min-height: 230px;
  padding: 30px;
  background: var(--white);
  border: 1px solid var(--line);
  text-decoration: none;
  transition: transform 180ms ease, box-shadow 180ms ease;
}

.source-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow);
}

.source-card span {
  color: var(--teal);
  font-size: 9px;
  font-weight: 900;
  letter-spacing: 0.11em;
}

.source-card strong {
  margin: auto 0 16px;
  font-family: var(--serif);
  font-size: 28px;
  font-weight: 400;
  line-height: 1.15;
}

.source-card small {
  color: var(--ink-soft);
}

.series-nav {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 20px;
  padding: 35px max(28px, calc((100vw - 1380px) / 2));
  color: #dce7df;
  background: #0a1c22;
  font-size: 11px;
}

.series-nav a {
  font-weight: 800;
  text-decoration: none;
}

.series-nav a:last-child {
  text-align: right;
}

.series-nav span {
  color: #708582;
  font-size: 9px;
  letter-spacing: 0.12em;
}

.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 700ms ease, transform 700ms ease;
}

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

@media (max-width: 1120px) {
  .topbar {
    grid-template-columns: 1fr auto;
  }

  .topbar nav {
    display: none;
  }

  .hero-grid {
    grid-template-columns: 1fr;
    width: min(900px, calc(100% - 48px));
  }

  .hero-stage {
    max-width: 680px;
    margin: 0 auto;
  }

  .master-chain {
    grid-template-columns: 1fr;
  }

  .master-chain > i {
    justify-self: center;
    transform: rotate(90deg);
  }

  .formula-head {
    grid-template-columns: 140px 1fr;
  }

  .formula-head p {
    grid-column: 2;
  }

  .protein-scale {
    grid-template-columns: repeat(3, 1fr);
  }

  .source-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 780px) {
  body {
    font-size: 16px;
  }

  .topbar {
    min-height: 62px;
    padding: 9px 16px;
  }

  .brand > span:last-child,
  .paper-link.secondary {
    display: none;
  }

  .paper-link {
    padding: 7px 11px;
  }

  .hero-grid {
    width: calc(100% - 36px);
    padding: 62px 0 42px;
  }

  .hero h1 {
    font-size: clamp(45px, 14.5vw, 68px);
  }

  .hero-stage {
    padding: 12px;
  }

  .hero-metrics {
    grid-template-columns: repeat(2, 1fr);
    width: calc(100% - 36px);
  }

  .hero-metrics div:nth-child(2) {
    border-right: 0;
  }

  .hero-metrics div {
    padding: 18px 10px;
  }

  .chapter {
    padding: 85px 18px;
  }

  .section-marker {
    margin-bottom: 40px;
  }

  .chapter-copy {
    display: block;
    margin-bottom: 50px;
  }

  .chapter-copy .lead {
    margin-top: 24px;
  }

  .reading-rule,
  .warning,
  .metric-note,
  .flow-note {
    display: block;
    margin-top: 32px;
    padding: 24px;
  }

  .reading-rule p,
  .warning p,
  .metric-note p,
  .flow-note p {
    margin-top: 10px;
  }

  .cg-lab,
  .noise-lab,
  .landscape-lab,
  .results-lab {
    grid-template-columns: 1fr;
  }

  .cg-stage,
  .noise-stage,
  .landscape-visual {
    min-height: 260px;
    padding: 10px;
  }

  .landscape-control,
  .results-controls {
    order: -1;
  }

  .formula-card {
    padding: 28px 18px;
  }

  .formula-head {
    display: block;
    margin-bottom: 28px;
  }

  .formula-head h3 {
    margin: 10px 0;
  }

  .equation {
    padding: 18px 0;
    font-size: clamp(19px, 6vw, 27px);
    text-align: left;
  }

  .equation.hero-equation {
    font-size: clamp(22px, 6.7vw, 33px);
  }

  .symbol-grid,
  .assumption-row,
  .term-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .symbol-grid div:nth-child(2),
  .assumption-row span:nth-child(2),
  .term-grid div:nth-child(2) {
    border-right: 0;
  }

  .concept-grid,
  .evidence-grid,
  .claim-grid {
    grid-template-columns: 1fr;
  }

  .two-clocks {
    grid-template-columns: 1fr;
  }

  .two-clocks > i {
    justify-self: center;
    margin: -8px 0;
  }

  .formula-walk {
    grid-template-columns: 1fr;
  }

  .formula-steps {
    grid-template-columns: repeat(5, minmax(86px, 1fr));
    overflow-x: auto;
  }

  .formula-step {
    display: block;
    min-width: 90px;
    padding: 14px 10px;
  }

  .formula-step span,
  .formula-step strong,
  .formula-step small {
    display: block;
  }

  .formula-display {
    min-height: 500px;
    padding: 30px 20px;
  }

  .mode-display {
    grid-template-columns: 1fr;
  }

  .mode-visual {
    min-height: 280px;
    padding: 10px;
  }

  .symmetry-board {
    grid-template-columns: 1fr;
  }

  .protein-scale {
    grid-template-columns: repeat(2, 1fr);
  }

  .bar-row {
    grid-template-columns: 70px 1fr;
  }

  .after-grid {
    grid-template-columns: 1fr;
  }

  .after-grid > i {
    justify-self: center;
    transform: rotate(90deg);
  }

  .source-grid {
    grid-template-columns: 1fr;
  }

  .series-nav {
    grid-template-columns: 1fr 1fr;
    padding: 28px 18px;
  }

  .series-nav span {
    display: none;
  }
}

@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;
  }

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