:root {
  --ink: #182129;
  --text: #35424b;
  --muted: #67737b;
  --subtle: #879198;
  --line: #dce3e6;
  --soft-line: #edf1f3;
  --surface: #f7f9fa;
  --paper: #ffffff;
  --teal: #267c75;
  --coral: #d96755;
  --blue: #2e73d2;
  --green: #459b68;
  --amber: #e2a02a;
  --violet: #8b62bd;
  --cyan: #2798bd;
  --display: "Instrument Sans", "Helvetica Neue", Arial, sans-serif;
  --body: "Source Serif 4", Georgia, serif;
  --utility: "Instrument Sans", "Helvetica Neue", Arial, sans-serif;
  --mono: "IBM Plex Mono", monospace;
  --header-height: 52px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 30px);
}

body {
  margin: 0;
  color: var(--text);
  background: var(--paper);
  font-family: var(--body);
  font-size: 17px;
  line-height: 1.75;
  letter-spacing: 0;
  -webkit-font-smoothing: antialiased;
}

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

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

button,
summary {
  font: inherit;
  letter-spacing: 0;
}

a:focus-visible,
button:focus-visible,
summary:focus-visible {
  outline: 3px solid rgba(46, 115, 210, 0.25);
  outline-offset: 3px;
}

.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 1000;
  padding: 8px 12px;
  color: white;
  background: var(--ink);
  border-radius: 4px;
  font-family: var(--utility);
  font-size: 13px;
  transform: translateY(-160%);
}

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

.scroll-progress {
  width: 100%;
  height: 3px;
  position: fixed;
  top: var(--header-height);
  left: 0;
  z-index: 200;
  background: linear-gradient(
    90deg,
    var(--blue) 0%,
    var(--green) 20%,
    var(--amber) 40%,
    var(--violet) 60%,
    var(--coral) 80%,
    var(--cyan) 100%
  );
  pointer-events: none;
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 50ms linear;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-height);
  background: rgba(255, 255, 255, 0.96);
  border-bottom: 1px solid rgba(220, 227, 230, 0.72);
  backdrop-filter: blur(16px);
}

.site-header.is-scrolled {
  border-color: var(--line);
  box-shadow: 0 4px 18px rgba(24, 33, 41, 0.04);
}

.header-inner {
  width: min(calc(100% - 64px), 1360px);
  height: 100%;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand,
.footer-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-family: var(--utility);
  font-weight: 700;
  white-space: nowrap;
}

.brand {
  font-size: 16px;
}

.brand img,
.footer-brand img {
  width: 38px;
  height: 38px;
  object-fit: contain;
}

.brand img {
  width: 34px;
  height: 34px;
}

.header-nav {
  display: flex;
  align-items: center;
  gap: 18px;
  color: #4f5b63;
  font-family: var(--utility);
  font-size: 14px;
  font-weight: 600;
}

.header-nav a {
  position: relative;
  padding: 11px 0 10px;
  line-height: 1;
}

.header-nav a::after {
  content: "";
  position: absolute;
  right: 0;
  bottom: 6px;
  left: 0;
  height: 2px;
  background: var(--teal);
  transform: scaleX(0);
  transform-origin: center;
  transition: transform 160ms ease;
}

.header-nav a:hover::after,
.header-nav a:focus-visible::after {
  transform: scaleX(1);
}

.header-nav a:hover,
.footer-links a:hover {
  color: var(--teal);
}

.github-link {
  display: inline-flex;
  align-items: center;
  gap: 7px;
}

.github-link svg {
  width: 17px;
  height: 17px;
}

.nav-toggle {
  width: 34px;
  height: 34px;
  padding: 0;
  display: none;
  align-items: center;
  justify-content: center;
  color: var(--ink);
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 6px;
  cursor: pointer;
}

.nav-toggle svg {
  width: 19px;
  height: 19px;
}

.hero {
  position: relative;
  width: 100%;
  min-height: 540px;
  overflow: hidden;
  background: linear-gradient(225deg, #d97b63 0%, #2d756d 44%, #153c3d 100%);
  -webkit-font-smoothing: auto;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  background-image: url("data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAoAAAAKCAYAAACNMs+9AAAAI0lEQVQoU2NkYGBg+M+ABaNgFIwCjAqGBoYGBgYGBgYGAAAO+CD0TA6o/cAAAAASUVORK5CYII=");
  background-repeat: repeat;
  opacity: 0.07;
  pointer-events: none;
}

.hero-inner {
  position: relative;
  z-index: 1;
  width: min(calc(100% - 64px), 1400px);
  min-height: 540px;
  margin: 0 auto;
  padding: 48px 0;
  display: block;
  font-family: "Rubik", var(--utility);
}

.hero-copy {
  max-width: none;
}

.eyebrow,
.section-kicker {
  margin: 0 0 14px;
  color: var(--teal);
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0;
}

.hero h1 {
  width: min(100%, 980px);
  margin: 0;
  color: #fff7d4;
  font-family: "Rubik", var(--display);
  font-size: 52px;
  line-height: 1.2;
  font-weight: bold;
  letter-spacing: 0;
}

.hero h1 span {
  white-space: nowrap;
}

.title-wide-break {
  white-space: normal;
}

.author-list {
  max-width: 820px;
  margin-top: 28px;
  display: flex;
  flex-wrap: wrap;
  gap: 4px 0;
  color: #ffffff;
  font-family: "Rubik", var(--utility);
  font-size: 17px;
  font-weight: bold;
  line-height: 1.65;
}

.author-list span {
  white-space: nowrap;
}

.author-list > span:not(:last-child)::after {
  content: ",";
  margin-right: 0.55em;
  color: rgba(255, 255, 255, 0.82);
}

.author-list a {
  text-decoration: underline;
  text-decoration-color: rgba(255, 255, 255, 0.78);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

.author-list a:hover {
  color: #ffd39d;
  text-decoration-color: currentColor;
}

.hero sup {
  color: #f7cf8b;
  font-weight: 600;
}

sup {
  color: var(--teal);
  font-family: var(--mono);
  font-size: 0.67em;
  font-weight: 500;
}

.affiliations {
  max-width: 820px;
  margin: 17px 0 0;
  color: rgba(255, 255, 255, 0.83);
  font-family: "Rubik", var(--utility);
  font-size: 14px;
  font-weight: 400;
  line-height: 1.72;
}

.affiliations span {
  white-space: nowrap;
}

.affiliations span:not(:last-child)::after {
  content: ",";
  margin-right: 0.45em;
  color: rgba(255, 255, 255, 0.6);
}

.author-note {
  margin: 14px 0 0;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 11px;
  color: rgba(255, 255, 255, 0.78);
  font-family: "Rubik", var(--utility);
  font-size: 13px;
  font-weight: 400;
  line-height: 1.4;
}

.author-note strong {
  color: #f7cf8b;
  font-family: var(--mono);
  font-size: 14px;
}

.role-divider {
  width: 1px;
  height: 13px;
  background: rgba(255, 255, 255, 0.27);
}

.hero-actions {
  margin-top: 24px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.button {
  min-height: 42px;
  padding: 8px 12px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  border: 2px solid rgba(1, 8, 67, 0.5);
  border-radius: 12px;
  font-family: "Rubik", var(--utility);
  font-size: 14px;
  font-weight: bold;
}

.button svg {
  width: 17px;
  height: 17px;
}

.button-primary {
  color: #173d3a;
  background: #fffce9;
  box-shadow: 0 8px 22px rgba(7, 28, 28, 0.18);
}

.button-primary:hover {
  color: #173d3a;
  background: #f5bd91;
}

.button-secondary {
  color: #173d3a;
  background: #fffce9;
  box-shadow: 0 8px 22px rgba(7, 28, 28, 0.18);
}

.button-secondary:hover {
  color: #173d3a;
  background: #f5bd91;
}

.hero-figure {
  width: 450px;
  max-width: 37%;
  min-width: 0;
  margin: 0;
  position: absolute;
  top: 105.5px;
  right: 25px;
}

.hero-figure-stage {
  height: auto;
  display: flex;
  align-items: center;
  justify-content: center;
  background: transparent;
}

.context-evolution {
  --evolution-offset: 0s;
  width: 100%;
  aspect-ratio: 450 / 329;
  position: relative;
  overflow: hidden;
  background: #ffffff;
  border: 1px solid rgba(220, 227, 230, 0.88);
  border-radius: 12px;
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.5);
  isolation: isolate;
}

.evolution-frame {
  width: 100%;
  height: 100%;
  position: absolute;
  inset: 0;
  z-index: 1;
  opacity: 0;
  transform: translateX(5%) scale(1.025);
  animation: evolution-frame-cycle 18s ease-in-out infinite both;
}

.evolution-frame-one { animation-delay: calc(0s - var(--evolution-offset)); }
.evolution-frame-two { animation-delay: calc(4.5s - var(--evolution-offset)); }
.evolution-frame-three { animation-delay: calc(9s - var(--evolution-offset)); }
.evolution-frame-four { animation-delay: calc(13.5s - var(--evolution-offset)); }

.evolution-frame img {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: cover;
}

.evolution-frame-four img {
  object-fit: contain;
}

.evolution-frame img.evolution-wordmark {
  width: 55%;
  height: auto;
  position: absolute;
  top: 23px;
  left: 50%;
  z-index: 2;
  object-fit: contain;
  pointer-events: none;
  transform: translateX(-50%);
}

.evolution-labels {
  min-width: 178px;
  height: 32px;
  position: absolute;
  bottom: 16px;
  left: 17px;
  z-index: 3;
  overflow: hidden;
  color: #173d3a;
  background: rgba(255, 255, 255, 0.9);
  border-left: 3px solid var(--teal);
  box-shadow: 0 4px 14px rgba(24, 33, 41, 0.08);
  backdrop-filter: blur(8px);
}

.evolution-label {
  height: 100%;
  padding: 0 10px;
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--utility);
  font-size: 11px;
  font-weight: 700;
  white-space: nowrap;
  opacity: 0;
  transform: translateY(7px);
  animation: evolution-label-cycle 18s ease-in-out infinite both;
}

.evolution-label strong {
  color: var(--teal);
  font-family: var(--mono);
  font-size: 9px;
  font-weight: 500;
}

.evolution-label-one { animation-delay: calc(0s - var(--evolution-offset)); }
.evolution-label-two { animation-delay: calc(4.5s - var(--evolution-offset)); }
.evolution-label-three { animation-delay: calc(9s - var(--evolution-offset)); }
.evolution-label-four { animation-delay: calc(13.5s - var(--evolution-offset)); }

.evolution-progress {
  position: absolute;
  right: 14px;
  bottom: 9px;
  z-index: 3;
  display: flex;
  gap: 2px;
}

.evolution-progress button {
  width: 25px;
  height: 19px;
  padding: 0;
  position: relative;
  overflow: hidden;
  background: transparent;
  border: 0;
  cursor: pointer;
}

.evolution-progress button::before,
.evolution-progress button::after {
  content: "";
  width: 19px;
  height: 3px;
  position: absolute;
  top: 8px;
  left: 3px;
}

.evolution-progress button::before {
  background: rgba(38, 124, 117, 0.2);
}

.evolution-progress button::after {
  background: var(--teal);
  transform: scaleX(0);
  transform-origin: left;
  animation-duration: 18s;
  animation-timing-function: linear;
  animation-iteration-count: infinite;
  animation-fill-mode: both;
  animation-delay: calc(0s - var(--evolution-offset));
}

.evolution-progress button:hover::before,
.evolution-progress button[aria-pressed="true"]::before {
  background: rgba(38, 124, 117, 0.34);
}

.evolution-progress button:focus-visible {
  outline: 2px solid rgba(38, 124, 117, 0.55);
  outline-offset: -2px;
}

.evolution-progress-one::after { animation-name: evolution-progress-one; }
.evolution-progress-two::after { animation-name: evolution-progress-two; }
.evolution-progress-three::after { animation-name: evolution-progress-three; }
.evolution-progress-four::after { animation-name: evolution-progress-four; }

.context-evolution.is-resetting .evolution-frame,
.context-evolution.is-resetting .evolution-label,
.context-evolution.is-resetting .evolution-progress button::after {
  animation: none;
}

@keyframes evolution-frame-cycle {
  0% {
    opacity: 0;
    transform: translateX(5%) scale(1.025);
  }
  1.5%, 22% {
    opacity: 1;
    transform: translateX(0) scale(1);
  }
  28%, 100% {
    opacity: 0;
    transform: translateX(-5%) scale(1.025);
  }
}

@keyframes evolution-label-cycle {
  0% {
    opacity: 0;
    transform: translateY(7px);
  }
  1.5%, 22% {
    opacity: 1;
    transform: translateY(0);
  }
  28%, 100% {
    opacity: 0;
    transform: translateY(-7px);
  }
}

@keyframes evolution-progress-one {
  0% {
    transform: scaleX(0);
  }
  24.9%, 100% {
    transform: scaleX(1);
  }
}

@keyframes evolution-progress-two {
  0%, 25% {
    transform: scaleX(0);
  }
  49.9%, 100% {
    transform: scaleX(1);
  }
}

@keyframes evolution-progress-three {
  0%, 50% {
    transform: scaleX(0);
  }
  74.9%, 100% {
    transform: scaleX(1);
  }
}

@keyframes evolution-progress-four {
  0%, 75% {
    transform: scaleX(0);
  }
  100% {
    transform: scaleX(1);
  }
}

.spectrum-rule {
  width: 100%;
  height: 5px;
  display: grid;
  grid-template-columns: repeat(6, 1fr);
}

.spectrum-rule span:nth-child(1) { background: var(--blue); }
.spectrum-rule span:nth-child(2) { background: var(--green); }
.spectrum-rule span:nth-child(3) { background: var(--amber); }
.spectrum-rule span:nth-child(4) { background: var(--violet); }
.spectrum-rule span:nth-child(5) { background: var(--coral); }
.spectrum-rule span:nth-child(6) { background: var(--cyan); }

.article-layout {
  width: min(calc(100% - 64px), 1080px);
  margin: 0 auto;
  padding: 92px 0 58px;
}

.survey-article {
  width: 100%;
  min-width: 0;
}

.survey-article > section {
  margin-bottom: 92px;
}

.survey-article > section:last-child {
  margin-bottom: 0;
}

.survey-article h2,
.survey-article h3,
.survey-article h4 {
  color: var(--ink);
  font-family: var(--display);
  letter-spacing: 0;
}

.survey-article h2 {
  margin: 0 0 24px;
  padding-bottom: 13px;
  font-size: 34px;
  line-height: 1.2;
  font-weight: 700;
  border-bottom: 1px solid var(--line);
}

.survey-article h3 {
  margin: 46px 0 15px;
  font-size: 23px;
  line-height: 1.3;
  font-weight: 700;
}

.survey-article h4 {
  margin: 27px 0 9px;
  font-size: 16px;
  line-height: 1.35;
}

.survey-article p {
  margin: 0 0 20px;
}

.survey-article strong {
  color: #243039;
  font-weight: 600;
}

.abstract {
  color: #6b7280;
  font-family: "Rubik", sans-serif;
  font-size: 1.1rem;
  line-height: 1.5;
}

.abstract strong {
  color: var(--teal);
}

#abstract h2,
#overview h2 {
  font-family: "Rubik", sans-serif;
}

#overview > p {
  color: #6b7280;
  font-family: "Rubik", sans-serif;
  font-size: 1.1rem;
  line-height: 1.5;
}

#overview > p strong {
  color: var(--teal);
}

#taxonomy,
#taxonomy h2,
#taxonomy h3,
#taxonomy h4 {
  font-family: "Rubik", sans-serif;
}

#taxonomy > p,
#taxonomy .perspective-intro > p {
  color: #6b7280;
  font-size: 1.1rem;
  line-height: 1.5;
}

#taxonomy strong {
  color: var(--teal);
}

.taxonomy-figure {
  margin-top: 32px;
  margin-bottom: 42px;
}

.wide-figure {
  width: 100%;
  margin: 36px 0 34px;
}

.wide-figure img {
  width: 100%;
  height: auto;
  display: block;
  border: 0;
}

.perspective-group {
  margin-top: 56px;
  padding-top: 30px;
  border-top: 1px solid var(--line);
}

.perspective-intro {
  margin-bottom: 24px;
  display: grid;
  grid-template-columns: 210px minmax(0, 1fr);
  gap: 34px;
}

.perspective-intro > div > span {
  color: var(--teal);
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
}

.perspective-intro h3 {
  margin: 6px 0 0;
  font-size: 22px;
  line-height: 1.25;
}

.perspective-intro > p {
  margin: 0;
}

.level-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px;
}

.level-card {
  --level-accent: var(--teal);
  --level-tint: #f2f8f7;
  min-width: 0;
  padding: 24px;
  display: flex;
  flex-direction: column;
  color: #56616a;
  background: #ffffff;
  border: 1px solid var(--line);
  border-top: 4px solid var(--level-accent);
  border-radius: 6px;
  box-shadow: 0 10px 28px rgba(24, 33, 41, 0.05);
  overflow: hidden;
  scroll-margin-top: calc(var(--header-height) + 30px);
}

.level-visual { --level-accent: var(--blue); --level-tint: #eef5ff; }
.level-spatial { --level-accent: var(--green); --level-tint: #edf8f1; }
.level-kinematic { --level-accent: var(--amber); --level-tint: #fff7e8; }
.level-interaction { --level-accent: var(--violet); --level-tint: #f6f0fb; }
.level-world { --level-accent: var(--coral); --level-tint: #fff1ee; }
.level-embodied { --level-accent: var(--cyan); --level-tint: #eef8fb; }

.level-card-header {
  margin-bottom: 18px;
  padding-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 14px;
  border-bottom: 1px solid var(--soft-line);
}

.level-card-header img {
  width: 58px;
  height: 58px;
  flex: 0 0 58px;
  object-fit: contain;
}

.level-card-header span {
  color: var(--level-accent);
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
}

.level-card-header h4 {
  margin: 4px 0 0;
  color: var(--ink);
  font-size: 24px;
  line-height: 1.2;
}

.card-section-label,
.trajectory-label {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 12px;
  font-weight: 650;
  text-transform: uppercase;
}

.card-section-label svg,
.trajectory-label svg {
  width: 16px;
  height: 16px;
  flex: 0 0 16px;
  stroke-width: 2;
}

.card-section-label {
  color: #68747c;
}

.level-scope {
  padding-bottom: 18px;
  border-bottom: 1px solid var(--soft-line);
}

.level-scope p {
  margin: 9px 0 0;
  font-size: 16px;
  line-height: 1.6;
}

.level-tasks {
  margin: 19px 0 23px;
}

.level-tasks .card-section-label {
  color: var(--level-accent);
}

.task-chips {
  margin: 11px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
  list-style: none;
}

.task-chips li {
  padding: 6px 9px;
  color: #46535b;
  background: var(--level-tint);
  border: 1px solid var(--soft-line);
  border-radius: 4px;
  font-size: 13px;
  line-height: 1.35;
}

.level-card strong {
  color: var(--level-accent);
}

.level-card .era-note {
  margin: auto -24px -24px;
  padding: 18px 24px 20px;
  color: #56616a;
  background: var(--level-tint);
  border-top: 2px solid var(--level-accent);
  border-left: 0;
  font-size: 15px;
  line-height: 1.55;
}

.trajectory-label {
  color: var(--level-accent);
}

.level-card .era-note p {
  margin: 8px 0 0;
}

#citation,
#citation h2 {
  font-family: "Rubik", sans-serif;
}

.citation-intro {
  margin: 0 0 24px;
  color: #6b7280;
  font-size: 1.1rem;
  line-height: 1.5;
}

.citation-panel {
  overflow: hidden;
  background: #ffffff;
  border: 1px solid var(--line);
  border-radius: 6px;
}

.citation-toolbar {
  min-height: 48px;
  padding: 7px 9px 7px 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: #56616a;
  background: var(--surface);
  border-bottom: 1px solid var(--line);
  font-size: 13px;
  font-weight: 650;
}

.citation-copy {
  width: 34px;
  height: 34px;
  padding: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--teal);
  background: #ffffff;
  border: 1px solid #cbd5d9;
  border-radius: 5px;
  cursor: pointer;
}

.citation-copy svg {
  width: 17px;
  height: 17px;
}

.citation-copy:hover:not(:disabled),
.citation-copy:focus-visible:not(:disabled) {
  background: #eef7f5;
  border-color: #9fc3be;
}

.citation-copy.is-copied {
  color: #ffffff;
  background: var(--teal);
  border-color: var(--teal);
}

.citation-copy:disabled {
  color: var(--subtle);
  background: #f3f5f6;
  cursor: not-allowed;
  opacity: 0.7;
}

.citation-code {
  min-height: 146px;
  margin: 0;
  padding: 22px;
  overflow-x: auto;
  color: #35424b;
  background: #fbfcfc;
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.7;
  white-space: pre-wrap;
}

.citation-code code {
  font: inherit;
}

.citation-code code:empty::before {
  content: "Citation information will be added when the survey is publicly available.";
  color: var(--muted);
  font-family: "Rubik", sans-serif;
  font-size: 15px;
}

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

.site-footer {
  width: min(calc(100% - 48px), 1240px);
  min-height: 158px;
  margin: 0 auto;
  padding: 40px 0 44px;
  display: grid;
  align-content: start;
  justify-items: center;
  gap: 9px;
  border-top: 1px solid var(--line);
  text-align: center;
}

.site-footer p {
  margin: 0;
  color: var(--muted);
  font-family: var(--utility);
}

.site-footer a {
  color: var(--teal-deep);
  font-weight: 650;
  text-decoration: underline;
  text-decoration-color: rgba(24, 102, 96, 0.34);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: color 160ms ease, text-decoration-color 160ms ease;
}

.site-footer a:hover,
.site-footer a:focus-visible {
  color: #b35c42;
  text-decoration-color: currentColor;
}

.footer-star {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  color: var(--ink) !important;
  font-size: 17px;
  font-weight: 600;
}

.footer-star svg {
  width: 19px;
  height: 19px;
  flex: 0 0 19px;
  color: #d9952d;
  fill: #f7d88c;
  stroke-width: 1.8;
}

.footer-credit {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0 4px;
  font-size: 13px;
  line-height: 1.6;
}

@media (max-width: 1120px) {
  .hero,
  .hero-inner {
    min-height: 600px;
  }

  .hero-inner {
    display: grid;
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    gap: 32px;
  }

  .hero h1 {
    width: auto;
  }

  .title-wide-break {
    display: none;
  }

  .author-list,
  .affiliations {
    max-width: none;
  }

  .hero-figure {
    width: 100%;
    max-width: 560px;
    position: static;
  }

  .context-evolution {
    width: 100%;
  }

  .hero h1 {
    font-size: 46px;
  }

  .wide-figure {
    width: 100%;
    margin-left: 0;
    margin-right: 0;
  }
}

@media (max-width: 880px) {
  .header-inner,
  .hero-inner,
  .article-layout,
  .site-footer {
    width: min(calc(100% - 32px), 760px);
  }

  .hero,
  .hero-inner {
    min-height: auto;
  }

  .header-inner {
    position: relative;
  }

  .nav-toggle {
    display: inline-flex;
  }

  .header-nav {
    width: min(300px, calc(100vw - 32px));
    padding: 8px;
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    color: #46535b;
    background: rgba(255, 255, 255, 0.99);
    border: 1px solid var(--line);
    border-radius: 6px;
    box-shadow: 0 16px 36px rgba(24, 33, 41, 0.14);
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transform: translateY(-8px);
    transition: opacity 160ms ease, transform 160ms ease, visibility 160ms ease;
  }

  .site-header.nav-open .header-nav {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transform: translateY(0);
  }

  .header-nav a {
    padding: 11px 12px;
    border-radius: 4px;
  }

  .header-nav a::after {
    display: none;
  }

  .header-nav a:hover,
  .header-nav a:focus-visible {
    color: var(--teal);
    background: #f2f7f6;
  }

  .github-link {
    justify-content: flex-start;
  }

  .hero-inner {
    padding: 44px 0 58px;
    grid-template-columns: 1fr;
    gap: 34px;
  }

  .hero-figure-stage {
    height: auto;
    min-height: 0;
  }

  .hero-figure {
    transform: none;
  }

  .article-layout {
    padding-top: 64px;
  }

  .wide-figure {
    width: 100%;
    margin-left: 0;
    margin-right: 0;
  }
}

@media (max-width: 760px) {
  .perspective-intro {
    grid-template-columns: 1fr;
    gap: 12px;
  }

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

@media (max-width: 640px) {
  body {
    font-size: 16px;
  }

  .brand span {
    font-size: 14px;
  }

  .hero-inner {
    padding-top: 34px;
  }

  .hero h1 {
    font-size: 38px;
    line-height: 1.2;
  }

  .author-list {
    font-size: 15px;
  }

  .affiliations {
    font-size: 13px;
  }

  .author-note {
    font-size: 13px;
  }

  .hero-figure-stage {
    min-height: 0;
  }

  .context-evolution {
    width: 90%;
    max-width: 90%;
  }

  .article-layout {
    padding-top: 54px;
    padding-bottom: 52px;
  }

  .survey-article > section {
    margin-bottom: 72px;
  }

  .survey-article h2 {
    font-size: 29px;
  }

  .survey-article h3 {
    font-size: 21px;
  }

  .abstract {
    font-size: 18px;
  }

  .perspective-group {
    margin-top: 46px;
    padding-top: 24px;
  }

  .level-card {
    padding: 20px;
  }

  .level-card-header img {
    width: 50px;
    height: 50px;
    flex-basis: 50px;
  }

  .level-card-header h4 {
    font-size: 22px;
  }

  .level-card .era-note {
    margin-right: -20px;
    margin-bottom: -20px;
    margin-left: -20px;
    padding: 16px 20px 18px;
  }

  .site-footer {
    min-height: auto;
    padding: 34px 0 38px;
    gap: 8px;
  }
}

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

  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
  }

  .evolution-frame,
  .evolution-label,
  .evolution-progress button::after {
    animation: none;
  }

  .context-evolution[data-active-stage="0"] .evolution-frame-one,
  .context-evolution[data-active-stage="0"] .evolution-label-one,
  .context-evolution[data-active-stage="1"] .evolution-frame-two,
  .context-evolution[data-active-stage="1"] .evolution-label-two,
  .context-evolution[data-active-stage="2"] .evolution-frame-three,
  .context-evolution[data-active-stage="2"] .evolution-label-three,
  .context-evolution[data-active-stage="3"] .evolution-frame-four,
  .context-evolution[data-active-stage="3"] .evolution-label-four {
    opacity: 1;
    transform: none;
  }

  .evolution-progress button[aria-pressed="true"]::after {
    transform: scaleX(1);
  }
}