/* Harness-Aware Evaluation
   1. Fonts
   2. Tokens
   3. Base
   4. Header and navigation
   5. Chapter controls
   6. Hero
   7. Chapters and figures
   8. Framework
   9. Harness
   10. Evidence
   11. Contributions
   12. Directions
   13. Citation
   14. Acknowledgements and footer
   15. Motion
   16. Breakpoints
*/

/* 1. Fonts */

@font-face {
  font-family: Karbon;
  src: url("../assets/fonts/Karbon-Light.woff2") format("woff2");
  font-weight: 300;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: Karbon;
  src: url("../assets/fonts/Karbon-LightItalic.woff2") format("woff2");
  font-weight: 300;
  font-style: italic;
  font-display: swap;
}

@font-face {
  font-family: Karbon;
  src: url("../assets/fonts/Karbon-Regular.woff2") format("woff2");
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: Karbon;
  src: url("../assets/fonts/Karbon-RegularItalic.woff2") format("woff2");
  font-weight: 400;
  font-style: italic;
  font-display: swap;
}

@font-face {
  font-family: Karbon;
  src: url("../assets/fonts/Karbon-Medium.woff2") format("woff2");
  font-weight: 500;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: Karbon;
  src: url("../assets/fonts/Karbon-MediumItalic.woff2") format("woff2");
  font-weight: 500;
  font-style: italic;
  font-display: swap;
}

@font-face {
  font-family: Karbon;
  src: url("../assets/fonts/Karbon-Semibold.woff2") format("woff2");
  font-weight: 600;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: Karbon;
  src: url("../assets/fonts/Karbon-SemiboldItalic.woff2") format("woff2");
  font-weight: 600;
  font-style: italic;
  font-display: swap;
}

@font-face {
  font-family: Karbon;
  src: url("../assets/fonts/Karbon-Bold.woff2") format("woff2");
  font-weight: 700;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: Karbon;
  src: url("../assets/fonts/Karbon-BoldItalic.woff2") format("woff2");
  font-weight: 700;
  font-style: italic;
  font-display: swap;
}

/* 2. Tokens */

:root {
  --font-sans: Karbon, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-display: Karbon, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  --text-xs: 0.8125rem;
  --text-sm: 0.9375rem;
  --text-md: 1.0625rem;
  --text-lg: 1.25rem;
  --text-xl: clamp(1.375rem, 2vw, 1.75rem);
  --text-2xl: clamp(1.5rem, 2.25vw, 1.875rem);
  --text-3xl: clamp(1.75rem, 3vw, 3rem);
  --text-4xl: clamp(2.875rem, 4.8vw, 5.125rem);
  --text-5xl: clamp(3.5rem, 6.1vw, 6.5rem);
  --ink: #10242c;
  --ink-soft: #49616b;
  --night: #071b24;
  --paper: #f7f7f2;
  --white: #ffffff;
  --line: #d9e0dd;
  --teal: #0e756f;
  --coral: #e66552;
  --gold: #b9882d;
  --purple: #76567e;
  --radius: 1.25rem;
  --shadow: 0 18px 60px rgb(7 27 36 / 9%);
  --shell: min(1160px, calc(100% - 3rem));
  --header-offset: 6.5rem;
}

/* 3. Base */

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 0;
  scroll-snap-type: y proximity;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: var(--font-sans);
  font-size: var(--text-lg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

body.nav-open {
  overflow: hidden;
}

a {
  color: inherit;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.2em;
}

img {
  display: block;
  max-width: 100%;
}

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

:focus-visible {
  outline: 3px solid var(--coral);
  outline-offset: 4px;
}

.shell {
  width: var(--shell);
  margin-inline: auto;
}

.narrow {
  max-width: 880px;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: fixed;
  top: 0.75rem;
  left: 0.75rem;
  z-index: 100;
  padding: 0.65rem 1rem;
  color: var(--white);
  background: var(--night);
  font-size: var(--text-md);
  transform: translateY(-160%);
}

.skip-link:focus {
  transform: none;
}

/* 4. Header and navigation */

.site-header {
  position: fixed;
  inset: 0.75rem 0 auto;
  z-index: 30;
  color: var(--white);
  pointer-events: none;
}

.site-header .nav {
  pointer-events: auto;
  transition: background 260ms ease, border-color 260ms ease, box-shadow 260ms ease;
}

.site-header.is-scrolled .nav {
  background: rgb(7 27 36 / 76%);
  border-color: rgb(255 255 255 / 13%);
  box-shadow: 0 10px 40px rgb(0 0 0 / 18%);
}

.nav {
  display: flex;
  min-height: 4.5rem;
  padding: 0.35rem 1rem;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  border: 1px solid transparent;
  border-radius: 1.2rem;
  backdrop-filter: blur(22px) saturate(140%);
  -webkit-backdrop-filter: blur(22px) saturate(140%);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.8rem;
  font-size: var(--text-md);
  font-weight: 700;
  letter-spacing: 0.02em;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  width: 2.3rem;
  height: 2.5rem;
  place-items: center;
  overflow: hidden;
}

.brand-mark img {
  width: 2.25rem;
  height: 2.6rem;
  object-fit: contain;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.7rem;
}

.nav-links a {
  color: rgb(255 255 255 / 78%);
  font-size: var(--text-md);
  font-weight: 600;
  text-decoration: none;
  transition: color 160ms ease;
}

.nav-links a:hover,
.nav-links a[aria-current="true"] {
  color: var(--white);
}

.nav-toggle {
  display: none;
  width: 2.8rem;
  height: 2.8rem;
  padding: 0.7rem;
  border: 0;
  color: inherit;
  background: transparent;
}

.nav-toggle span:not(.sr-only) {
  display: block;
  height: 2px;
  margin: 5px 0;
  background: currentColor;
  transition: transform 160ms ease, opacity 160ms ease;
}

/* 5. Chapter controls */

.deck-controls {
  position: fixed;
  z-index: 25;
  right: clamp(0.85rem, 2vw, 2rem);
  bottom: clamp(1rem, 3vh, 2rem);
  display: grid;
  width: 3.25rem;
  padding: 0.35rem;
  place-items: center;
  color: var(--white);
  background: rgb(7 27 36 / 76%);
  border: 1px solid rgb(255 255 255 / 15%);
  border-radius: 999px;
  box-shadow: 0 16px 44px rgb(0 0 0 / 22%);
  backdrop-filter: blur(22px) saturate(150%);
  -webkit-backdrop-filter: blur(22px) saturate(150%);
}

.deck-controls button {
  display: grid;
  width: 2.55rem;
  height: 2.55rem;
  padding: 0;
  place-items: center;
  color: inherit;
  background: transparent;
  border: 0;
  border-radius: 50%;
  cursor: pointer;
  transition: color 160ms ease, background 160ms ease, transform 160ms ease;
}

.deck-controls button:hover:not(:disabled) {
  color: var(--night);
  background: #9ed8d1;
  transform: scale(1.04);
}

.deck-controls button:disabled {
  opacity: 0.25;
  cursor: default;
}

.deck-controls svg,
.scroll-cue svg {
  width: 1.2rem;
  fill: none;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.7;
}

/* 6. Hero */

.hero {
  position: relative;
  overflow: hidden;
  color: var(--white);
  background:
    radial-gradient(circle at 72% 30%, rgb(14 117 111 / 30%), transparent 28rem),
    linear-gradient(122deg, #071b24 0%, #0b2832 55%, #12333a 100%);
}

.hero::before {
  position: absolute;
  inset: 0;
  pointer-events: none;
  content: "";
  opacity: 0.35;
  background-image:
    linear-gradient(rgb(255 255 255 / 4%) 1px, transparent 1px),
    linear-gradient(90deg, rgb(255 255 255 / 4%) 1px, transparent 1px);
  background-size: 62px 62px;
  mask-image: linear-gradient(to right, transparent, black 60%);
}

.hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  padding-block: var(--header-offset) clamp(4rem, 10vh, 7rem);
  align-items: center;
  grid-template-columns: minmax(0, 1.1fr) minmax(26rem, 0.9fr);
  gap: clamp(3rem, 5vw, 5.5rem);
}

.eyebrow,
.section-kicker {
  margin: 0 0 1rem;
  color: var(--teal);
  font-size: var(--text-sm);
  font-weight: 700;
  letter-spacing: 0.15em;
  text-transform: uppercase;
}

.eyebrow {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  color: #86d5ce;
}

.eyebrow span {
  width: 2rem;
  height: 1px;
  background: currentColor;
}

.hero h1 {
  max-width: 760px;
  margin: 0;
  font-family: var(--font-display);
  font-size: var(--text-5xl);
  font-weight: 300;
  letter-spacing: -0.03em;
  line-height: 1.02;
}

.hero h1 span {
  display: block;
}

.hero h1 em {
  color: #86d5ce;
  font-weight: 400;
}

.subtitle {
  margin: 1.2rem 0 0;
  color: #f4c4b8;
  font-family: var(--font-display);
  font-size: var(--text-xl);
}

.lede {
  max-width: 38rem;
  margin: 2rem 0;
  color: rgb(255 255 255 / 74%);
  font-size: var(--text-xl);
}

.authors {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.4rem;
}

.authors a {
  color: var(--white);
  font-size: var(--text-md);
  font-weight: 700;
}

.affiliations {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.2rem;
  margin: 0.35rem 0 0;
  color: rgb(255 255 255 / 52%);
  font-size: var(--text-md);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
  margin-top: 2.25rem;
}

.button {
  display: inline-flex;
  min-height: 3rem;
  padding: 0.6rem 1.15rem;
  align-items: center;
  justify-content: center;
  gap: 0.7rem;
  border: 1px solid rgb(255 255 255 / 24%);
  border-radius: 999px;
  font-size: var(--text-md);
  font-weight: 700;
  text-decoration: none;
  transition: transform 160ms ease, background 160ms ease, border-color 160ms ease;
}

.button img {
  width: 1.9rem;
  height: 1.3rem;
  object-fit: contain;
  filter: grayscale(1) brightness(0) invert(1);
}

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

.button-primary img {
  filter: grayscale(1) brightness(0);
}

.button-secondary:hover {
  background: rgb(255 255 255 / 10%);
  border-color: rgb(255 255 255 / 46%);
  transform: translateY(-2px);
}

.is-placeholder {
  cursor: not-allowed;
}

.hero-visual {
  position: relative;
  width: min(100%, 32.5rem);
  aspect-ratio: 1;
  margin-inline: auto;
}

.hero-visual::before,
.hero-visual::after {
  position: absolute;
  inset: 9%;
  border: 1px solid rgb(255 255 255 / 15%);
  border-radius: 50%;
  content: "";
}

.hero-visual::after {
  inset: 24%;
  border-style: dashed;
}

.score-card {
  position: absolute;
  inset: 50% auto auto 50%;
  display: grid;
  width: 10.5rem;
  height: 10.5rem;
  place-content: center;
  text-align: center;
  background: rgb(7 27 36 / 78%);
  border: 1px solid rgb(255 255 255 / 20%);
  border-radius: 50%;
  box-shadow: 0 0 80px rgb(14 117 111 / 32%);
  transform: translate(-50%, -50%);
}

.score-card span,
.score-card small {
  color: rgb(255 255 255 / 55%);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.score-card strong {
  margin: 0.15rem 0;
  color: var(--white);
  font-family: var(--font-display);
  font-size: var(--text-3xl);
  font-weight: 300;
  line-height: 1;
}

.orbit {
  position: absolute;
  z-index: 2;
  display: grid;
  width: 6.25rem;
  aspect-ratio: 1;
  place-content: center;
  text-align: center;
  border-radius: 50%;
  box-shadow: 0 12px 28px rgb(0 0 0 / 20%);
}

.orbit span {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  line-height: 1;
}

.orbit small {
  margin-top: 0.25rem;
  font-size: var(--text-xs);
  font-weight: 700;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

.orbit-model {
  top: 4%;
  left: 42%;
  color: var(--night);
  background: #acd8d4;
}

.orbit-harness {
  top: 42%;
  right: 0;
  color: var(--night);
  background: #f09a86;
}

.orbit-environment {
  bottom: 3%;
  left: 38%;
  background: #3c745f;
}

.orbit-evaluator {
  top: 42%;
  left: 0;
  background: #795b82;
}

.protocol-ring {
  position: absolute;
  top: 7%;
  left: 0;
  padding: 0.45rem 0.8rem;
  color: #f7d89c;
  background: var(--night);
  border: 1px solid #b9882d;
  border-radius: 999px;
  font-size: var(--text-xs);
  font-weight: 700;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  transform: rotate(-8deg);
}

.hero-rule {
  position: absolute;
  right: 0;
  bottom: 0;
  left: 0;
  height: 0.45rem;
  background: linear-gradient(90deg, var(--teal) 0 25%, var(--coral) 25% 50%, var(--gold) 50% 75%, var(--purple) 75%);
}

.scroll-cue {
  position: absolute;
  z-index: 3;
  bottom: 1.8rem;
  left: 50%;
  display: flex;
  align-items: center;
  gap: 0.55rem;
  color: rgb(255 255 255 / 58%);
  font-size: var(--text-sm);
  font-weight: 600;
  letter-spacing: 0.08em;
  text-decoration: none;
  text-transform: uppercase;
  transform: translateX(-50%);
}

.scroll-cue svg {
  animation: cue-float 1.8s ease-in-out infinite;
}

/* 7. Chapters and figures */

.hero,
.section {
  display: flex;
  min-height: 100vh;
  min-height: 100svh;
  align-items: center;
  scroll-snap-align: start;
}

.section {
  padding-block: var(--header-offset);
  background: linear-gradient(180deg, var(--band-top), var(--band-bottom));
}

.section-heading {
  max-width: 46rem;
  margin-bottom: 3.6rem;
}

.split-heading {
  display: grid;
  max-width: none;
  align-items: end;
  grid-template-columns: minmax(0, 1.5fr) minmax(16rem, 0.7fr);
  gap: 5rem;
}

.section h2 {
  margin: 0;
  font-family: var(--font-display);
  font-size: var(--text-4xl);
  font-weight: 300;
  letter-spacing: -0.025em;
  line-height: 1.08;
}

.split-heading > p {
  margin: 0 0 0.5rem;
  color: var(--ink-soft);
}

.intro-section {
  --band-top: #f2f7f4;
  --band-bottom: #ffffff;
}

.framework-section {
  --band-top: #ffffff;
  --band-bottom: #f1f3ee;
}

.evidence-section {
  --band-top: #f2f7f4;
  --band-bottom: #ffffff;
}

.contributions-section {
  --band-top: #ffffff;
  --band-bottom: #f1f3ee;
}

.citation-section {
  --band-top: #f2f7f4;
  --band-bottom: #ffffff;
}

/* A rule, not a drop cap: the abstract opens on "LLM". */
.abstract {
  margin: 2.5rem 0 0;
  padding-left: 1.6rem;
  border-left: 3px solid var(--coral);
  color: #304950;
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  line-height: 1.65;
}

.paper-figure {
  margin: 0;
}

.paper-figure img {
  display: block;
  width: 100%;
  max-width: var(--figure-max, 100%);
  height: auto;
  margin-inline: auto;
  background: var(--white);
}

.paper-figure figcaption {
  margin-top: 0.8rem;
  color: var(--ink-soft);
  font-size: var(--text-sm);
  line-height: 1.45;
}

.paper-figure--compact {
  --figure-max: 18.75rem;
}

.paper-figure--wide {
  --figure-max: 28.75rem;
}

.framed-figure,
.timeline-figure {
  margin-top: 4rem;
  padding: 1rem;
  background: var(--white);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.framed-figure {
  border: 1px solid var(--line);
}

.framed-figure figcaption {
  padding-inline: 0.4rem;
}

/* 8. Framework */

.factor-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
}

.factor-card {
  position: relative;
  min-height: 19rem;
  padding: 1.7rem;
  overflow: hidden;
  color: var(--white);
  border-radius: var(--radius);
}

.factor-card::after {
  position: absolute;
  right: -2.5rem;
  bottom: -4.5rem;
  width: 11rem;
  aspect-ratio: 1;
  border: 1px solid rgb(255 255 255 / 15%);
  border-radius: 50%;
  content: "";
}

.factor-model { background: #315f80; }
.factor-harness { background: #a84f40; }
.factor-environment { background: #39705e; }
.factor-evaluator { background: #6e5278; }

.factor-symbol {
  display: grid;
  width: 4rem;
  aspect-ratio: 1;
  place-items: center;
  margin-bottom: 3rem;
  background: rgb(255 255 255 / 13%);
  border: 1px solid rgb(255 255 255 / 20%);
  border-radius: 50%;
  font-family: var(--font-display);
  font-size: var(--text-2xl);
}

.factor-number {
  margin: 0;
  color: rgb(255 255 255 / 55%);
  font-size: var(--text-sm);
  font-weight: 700;
  letter-spacing: 0.12em;
}

.factor-card h3,
.mechanism-grid h3,
.direction-list h3 {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 400;
}

.factor-card h3 {
  margin: 0.15rem 0 0.65rem;
}

.factor-card p:last-child {
  margin: 0;
  color: rgb(255 255 255 / 73%);
  font-size: var(--text-md);
}

.protocol-strip {
  display: flex;
  margin-top: 1rem;
  padding: 1.1rem 1.4rem;
  align-items: center;
  gap: 2rem;
  color: var(--white);
  background: var(--night);
  border-radius: 0.75rem;
}

.protocol-strip > span {
  color: #f4c4b8;
  font-size: var(--text-sm);
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.protocol-strip ul {
  display: flex;
  padding: 0;
  margin: 0;
  flex: 1;
  justify-content: space-around;
  gap: 1rem;
  list-style: none;
}

.protocol-strip li {
  color: rgb(255 255 255 / 72%);
  font-size: var(--text-md);
}

/* 9. Harness */

.harness-section {
  --band-top: #12323a;
  --band-bottom: var(--night);
  color: var(--white);
}

.harness-section .section-kicker,
.directions-section .section-kicker {
  color: #86d5ce;
}

.mechanism-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border-top: 1px solid rgb(255 255 255 / 18%);
  border-left: 1px solid rgb(255 255 255 / 18%);
}

.mechanism-grid article {
  min-height: 15rem;
  padding: 2rem;
  border-right: 1px solid rgb(255 255 255 / 18%);
  border-bottom: 1px solid rgb(255 255 255 / 18%);
  transition: background 180ms ease;
}

.mechanism-grid article:hover {
  background: rgb(255 255 255 / 4%);
}

.mechanism-grid span,
.contribution-list article > span,
.direction-list span {
  font-size: var(--text-sm);
  font-weight: 700;
}

.mechanism-grid span {
  color: var(--coral);
  font-family: var(--font-display);
}

.mechanism-grid h3 {
  margin: 2.8rem 0 0.7rem;
}

.mechanism-grid p,
.direction-list p {
  margin: 0;
  font-size: var(--text-md);
}

.mechanism-grid p {
  color: rgb(255 255 255 / 60%);
}

.shift-block {
  display: grid;
  align-items: center;
  grid-template-columns: minmax(0, 0.85fr) minmax(18rem, 0.75fr);
  gap: clamp(2rem, 4vw, 4.5rem);
  margin-top: 4.5rem;
}

.shift-lead h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: var(--text-3xl);
  font-weight: 300;
  letter-spacing: -0.03em;
  line-height: 1.1;
}

.shift-lead p:last-child {
  max-width: 34rem;
  margin: 1.25rem 0 0;
  color: rgb(255 255 255 / 62%);
  font-size: var(--text-md);
}

.shift-orbit {
  position: relative;
  width: min(100%, 30rem);
  aspect-ratio: 1;
  margin-inline: auto;
}

.shift-orbit::before,
.shift-orbit::after {
  position: absolute;
  inset: 10%;
  border: 1px solid rgb(255 255 255 / 16%);
  border-radius: 50%;
  content: "";
}

.shift-orbit::after {
  inset: 26%;
  border-style: dashed;
}

.shift-core {
  position: absolute;
  inset: 50% auto auto 50%;
  display: grid;
  width: 9.5rem;
  height: 9.5rem;
  place-content: center;
  text-align: center;
  background: rgb(7 27 36 / 82%);
  border: 1px solid rgb(255 255 255 / 22%);
  border-radius: 50%;
  box-shadow: 0 0 70px rgb(14 117 111 / 28%);
  transform: translate(-50%, -50%);
}

.shift-core span {
  color: rgb(255 255 255 / 55%);
  font-size: var(--text-xs);
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.shift-core strong {
  color: var(--white);
  font-family: var(--font-display);
  font-size: var(--text-3xl);
  font-weight: 300;
  line-height: 1;
}

.shift-node {
  position: absolute;
  z-index: 1;
  display: grid;
  width: 7.4rem;
  aspect-ratio: 1;
  place-content: center;
  text-align: center;
  border-radius: 50%;
  box-shadow: 0 12px 28px rgb(0 0 0 / 22%);
}

.shift-node strong {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 400;
  line-height: 1;
}

.shift-node span,
.shift-node small {
  font-size: var(--text-xs);
  font-weight: 700;
  letter-spacing: 0.04em;
}

.shift-node small {
  margin-top: 0.15rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.shift-context {
  top: 2%;
  left: 38%;
  color: var(--night);
  background: #acd8d4;
}

.shift-tools {
  top: 38%;
  right: 0;
  color: var(--night);
  background: #f09a86;
}

.shift-verifier {
  bottom: 2%;
  left: 36%;
  color: var(--white);
  background: #3c745f;
}

.shift-planning {
  top: 38%;
  left: 0;
  color: var(--white);
  background: #795b82;
}

/* 10. Evidence */

.stats-grid {
  display: grid;
  margin-bottom: 3rem;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
}

.stats-grid article {
  display: grid;
  min-height: 9rem;
  padding: 1.2rem;
  align-content: space-between;
  border-top: 3px solid var(--coral);
  background: #f4f4ef;
}

.stats-grid article:nth-child(2) { border-color: var(--teal); }
.stats-grid article:nth-child(3) { border-color: var(--gold); }
.stats-grid article:nth-child(4) { border-color: var(--purple); }

.stats-grid strong {
  font-family: var(--font-display);
  font-size: 3rem;
  font-weight: 300;
  letter-spacing: -0.04em;
  line-height: 1;
}

.stats-grid span {
  color: var(--ink-soft);
  font-size: var(--text-sm);
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.chart-grid {
  display: grid;
  grid-template-columns: repeat(2, 18.75rem);
  justify-content: center;
  gap: 1.5rem;
  align-items: start;
}

.chart-grid .paper-figure--wide {
  grid-column: 1 / -1;
  --figure-max: 100%;
}

.chart-grid .paper-figure {
  padding: 1rem 1rem 1.15rem;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 0.8rem;
}

.chart-grid figcaption {
  text-align: center;
}

/* 11. Contributions */

.contribution-list {
  border-top: 1px solid #cbd4cf;
}

.contribution-list article {
  display: grid;
  padding: 2.25rem 0;
  align-items: start;
  border-bottom: 1px solid #cbd4cf;
  grid-template-columns: 4rem 1fr;
}

.contribution-list article > span {
  color: var(--coral);
  font-family: var(--font-display);
}

.contribution-list h2 {
  font-size: var(--text-3xl);
}

.contribution-list p {
  max-width: 42rem;
  margin: 0.75rem 0 0;
  color: var(--ink-soft);
}

/* 12. Directions */

.directions-section {
  --band-top: var(--night);
  --band-bottom: #12323a;
  color: var(--white);
}

.direction-list {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 1rem;
}

.direction-list article {
  min-height: 17rem;
  padding: 1.5rem;
  background: rgb(255 255 255 / 5%);
  border: 1px solid rgb(255 255 255 / 12%);
  border-radius: 0.8rem;
  grid-column: span 2;
}

.direction-list article:nth-child(4) {
  grid-column: 2 / span 2;
}

.direction-list span {
  color: #f2a793;
}

.direction-list h3 {
  margin: 3.6rem 0 0.7rem;
}

.direction-list p {
  color: rgb(255 255 255 / 62%);
}

/* 13. Citation */

.closing-stack {
  display: grid;
  gap: 2.75rem;
}

.citation-grid {
  display: grid;
  align-items: center;
  grid-template-columns: 0.7fr 1.3fr;
  gap: 3rem;
}

.citation-grid > div:first-child > p:last-child {
  color: var(--ink-soft);
  font-size: var(--text-lg);
}

.citation-box {
  position: relative;
  overflow: hidden;
  color: #e6efed;
  background: var(--night);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.citation-box pre {
  padding: 2rem 2rem 4.5rem;
  margin: 0;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: var(--text-md);
  line-height: 1.7;
}

.copy-button {
  position: absolute;
  right: 1rem;
  bottom: 1rem;
  padding: 0.65rem 0.9rem;
  color: var(--night);
  background: #9ed8d1;
  border: 0;
  border-radius: 999px;
  cursor: pointer;
  font: inherit;
  font-size: var(--text-sm);
  font-weight: 700;
}

/* 14. Acknowledgements and footer */

.citation-section {
  --band-bottom: var(--paper);
}

.ack-band {
  display: grid;
  align-items: center;
  grid-template-columns: 11rem minmax(0, 1fr) auto;
  gap: 2rem;
  padding-top: 2rem;
  border-top: 1px solid var(--line);
}

.ack-band .section-kicker,
.ack-band p {
  margin: 0;
}

.ack-band p:not(.section-kicker) {
  color: var(--ink-soft);
  font-size: var(--text-md);
}

.partner-logos {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 2rem;
}

.partner-logos img {
  width: auto;
  max-width: 7.5rem;
  max-height: 4.5rem;
  object-fit: contain;
}

.partner-logos a:first-child img {
  max-height: 5.5rem;
}

.site-footer {
  color: rgb(255 255 255 / 60%);
  background: var(--night);
}

.footer-inner {
  display: flex;
  min-height: 6.5rem;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  font-size: var(--text-md);
}

.footer-inner a {
  color: var(--white);
}

/* 15. Motion */

@keyframes cue-float {
  0%,
  100% { transform: translateY(0); }
  50% { transform: translateY(0.3rem); }
}

.js [data-reveal] {
  opacity: 0;
  transform: translateY(1.25rem);
  transition:
    opacity 680ms ease,
    transform 680ms cubic-bezier(0.22, 1, 0.36, 1);
  transition-delay: var(--reveal-delay, 0ms);
}

.js [data-reveal].is-revealed {
  opacity: 1;
  transform: none;
}

.hero-visual[data-reveal] { --reveal-delay: 120ms; }

.shell > [data-reveal]:nth-child(2) { --reveal-delay: 80ms; }
.shell > [data-reveal]:nth-child(3) { --reveal-delay: 150ms; }
.shell > [data-reveal]:nth-child(4) { --reveal-delay: 210ms; }

.factor-grid > [data-reveal]:nth-child(2),
.stats-grid > [data-reveal]:nth-child(2),
.chart-grid > [data-reveal]:nth-child(2),
.direction-list > [data-reveal]:nth-child(2) { --reveal-delay: 70ms; }

.factor-grid > [data-reveal]:nth-child(3),
.stats-grid > [data-reveal]:nth-child(3),
.chart-grid > [data-reveal]:nth-child(3),
.direction-list > [data-reveal]:nth-child(3),
.mechanism-grid > [data-reveal]:nth-child(2) { --reveal-delay: 140ms; }

.factor-grid > [data-reveal]:nth-child(4),
.stats-grid > [data-reveal]:nth-child(4),
.direction-list > [data-reveal]:nth-child(4),
.mechanism-grid > [data-reveal]:nth-child(3),
.contribution-list > [data-reveal]:nth-child(2) { --reveal-delay: 210ms; }

.direction-list > [data-reveal]:nth-child(5),
.mechanism-grid > [data-reveal]:nth-child(4),
.contribution-list > [data-reveal]:nth-child(3) { --reveal-delay: 280ms; }

.mechanism-grid > [data-reveal]:nth-child(5) { --reveal-delay: 350ms; }
.mechanism-grid > [data-reveal]:nth-child(6) { --reveal-delay: 420ms; }

/* 16. Breakpoints */

@media (min-width: 1500px) {
  :root {
    --shell: min(1320px, calc(100% - 4rem));
  }

  .hero h1 {
    font-size: clamp(5.25rem, 5.2vw, 7.25rem);
  }

  .hero-visual {
    width: min(100%, 36rem);
  }
}

@media (max-width: 960px) {
  .hero-grid {
    grid-template-columns: minmax(0, 1fr);
    gap: 2.5rem;
  }

  .hero-visual {
    width: min(80vw, 28rem);
  }

  .split-heading,
  .citation-grid,
  .shift-block {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }

  .factor-grid,
  .stats-grid {
    grid-template-columns: 1fr 1fr;
  }

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

  .direction-list {
    grid-template-columns: 1fr 1fr;
  }

  .direction-list article,
  .direction-list article:nth-child(4) {
    grid-column: auto;
  }

  .direction-list article:last-child {
    grid-column: 1 / -1;
  }

  .ack-band {
    grid-template-columns: 1fr auto;
  }

  .ack-band .section-kicker {
    grid-column: 1 / -1;
  }

  .partner-logos {
    justify-content: flex-start;
  }
}

@media (max-width: 700px) {
  :root {
    --shell: calc(100% - 2rem);
  }

  .nav-toggle {
    display: block;
    cursor: pointer;
  }

  .nav-links {
    position: fixed;
    inset: 4.6rem 0 0;
    display: grid;
    padding: 2rem;
    align-content: start;
    background: rgb(7 27 36 / 98%);
    opacity: 0;
    pointer-events: none;
    transform: translateY(-0.75rem);
    transition: opacity 160ms ease, transform 160ms ease;
  }

  .nav-links a {
    padding: 0.8rem 0;
    font-family: var(--font-display);
    font-size: var(--text-2xl);
  }

  .nav-open .nav-links {
    opacity: 1;
    pointer-events: auto;
    transform: none;
  }

  .nav-open .nav-toggle span:nth-child(2) {
    transform: translateY(7px) rotate(45deg);
  }

  .nav-open .nav-toggle span:nth-child(3) {
    opacity: 0;
  }

  .nav-open .nav-toggle span:nth-child(4) {
    transform: translateY(-7px) rotate(-45deg);
  }

  .hero-grid {
    padding-block: 7rem 4.5rem;
  }

  .hero h1 {
    font-size: clamp(2.5rem, 11vw, 3.625rem);
    letter-spacing: -0.04em;
  }

  .authors {
    align-items: flex-start;
    flex-direction: column;
    gap: 0.35rem;
  }

  .hero-visual {
    width: min(100%, 22rem);
  }

  .orbit {
    width: 5.2rem;
  }

  .score-card {
    width: 8.4rem;
    height: 8.4rem;
  }

  .factor-grid,
  .mechanism-grid,
  .stats-grid,
  .direction-list,
  .chart-grid {
    grid-template-columns: minmax(0, 1fr);
    justify-content: stretch;
  }

  .shift-orbit {
    width: min(100%, 22rem);
  }

  .factor-card {
    min-height: 14rem;
  }

  .protocol-strip {
    display: block;
  }

  .protocol-strip ul {
    display: grid;
    margin-top: 0.8rem;
    grid-template-columns: 1fr 1fr;
  }

  .direction-list article,
  .direction-list article:last-child {
    min-height: 0;
    grid-column: auto;
  }

  .contribution-list article {
    grid-template-columns: 2.5rem 1fr;
  }

  .citation-box pre {
    padding-inline: 1.25rem;
    font-size: var(--text-sm);
  }

  .ack-band {
    grid-template-columns: 1fr;
    gap: 1rem;
  }

  .partner-logos {
    justify-content: flex-start;
  }

  .footer-inner {
    min-height: 0;
    padding-block: 2rem;
    align-items: flex-start;
    flex-direction: column;
    justify-content: center;
    gap: 0.4rem;
  }

  .footer-inner p {
    margin: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-snap-type: none;
  }

  .js [data-reveal] {
    opacity: 1;
    transform: none;
  }

  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}