:root {
  --bg: #f6f3ec;
  --ink: #132126;
  --muted: #5f6d68;
  --surface: #fffdf8;
  --surface-strong: #ffffff;
  --line: #d8cec0;
  --teal: #2f7b75;
  --teal-dark: #183f43;
  --gold: #e5b84b;
  --coral: #d8694f;
  --violet: #5c6bc0;
  --sage: #7f9565;
  --rose: #b94f6f;
  --shadow: 0 22px 58px rgba(19, 33, 38, 0.13);
  --radius: 8px;
  --header-height: 76px;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  margin: 0;
  color: var(--ink);
  background:
    linear-gradient(145deg, rgba(47, 123, 117, 0.11), transparent 34%),
    linear-gradient(235deg, rgba(229, 184, 75, 0.14), transparent 37%),
    linear-gradient(315deg, rgba(216, 105, 79, 0.09), transparent 35%),
    var(--bg);
  font-size: 16px;
  line-height: 1.5;
}

button,
input {
  font: inherit;
}

button {
  cursor: pointer;
}

button:focus-visible,
input:focus-visible,
a:focus-visible {
  outline: 3px solid rgba(92, 107, 192, 0.45);
  outline-offset: 3px;
}

[hidden] {
  display: none !important;
}

h1,
h2,
h3,
p {
  overflow-wrap: anywhere;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1,
h2,
h3 {
  color: var(--ink);
  line-height: 1.05;
  letter-spacing: 0;
}

h1 {
  max-width: 880px;
  margin-bottom: 20px;
  font-size: clamp(2.35rem, 5vw, 4.7rem);
}

h2 {
  margin-bottom: 12px;
  font-size: clamp(1.45rem, 2.4vw, 2.25rem);
}

p {
  color: var(--muted);
}

.sr-only,
.skip-link:not(:focus) {
  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:focus {
  position: fixed;
  z-index: 80;
  top: 12px;
  left: 12px;
  padding: 10px 14px;
  border-radius: var(--radius);
  background: var(--ink);
  color: #fff;
}

.app-header {
  position: sticky;
  top: 0;
  z-index: 40;
  border-bottom: 1px solid rgba(216, 206, 192, 0.9);
  background: rgba(246, 243, 236, 0.92);
  backdrop-filter: blur(18px);
}

.app-header[data-elevated="true"] {
  box-shadow: 0 12px 34px rgba(19, 33, 38, 0.09);
}

.header-inner {
  width: min(1220px, calc(100% - 32px));
  min-height: var(--header-height);
  margin: 0 auto;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 18px;
}

.brand {
  min-width: 0;
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: inherit;
  text-decoration: none;
  font-weight: 900;
}

.brand-mark {
  width: 46px;
  height: 46px;
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  position: relative;
  border: 1px solid rgba(19, 33, 38, 0.13);
  border-radius: 50%;
  background:
    radial-gradient(circle at 50% 50%, var(--surface) 0 28%, transparent 29%),
    conic-gradient(from 15deg, var(--teal), var(--gold), var(--coral), var(--violet), var(--teal));
}

.brand-mark i {
  position: absolute;
  border: 2px solid var(--teal-dark);
  border-radius: 50%;
}

.brand-mark i:nth-child(1) {
  width: 34px;
  height: 34px;
}

.brand-mark i:nth-child(2) {
  width: 25px;
  height: 25px;
}

.brand-mark i:nth-child(3) {
  width: 16px;
  height: 16px;
}

.brand-mark i:nth-child(4) {
  width: 6px;
  height: 6px;
  background: var(--teal-dark);
}

.window-tabs {
  justify-self: center;
  min-width: min(100%, 430px);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 6px;
  padding: 5px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(255, 253, 248, 0.72);
}

.window-tab {
  min-height: 42px;
  padding: 8px 12px;
  border: 0;
  border-radius: 6px;
  background: transparent;
  color: var(--muted);
  font-weight: 850;
}

.window-tab.is-active {
  background: var(--ink);
  color: #fff;
}

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

.icon-button {
  width: 44px;
  height: 44px;
  display: inline-grid;
  place-items: center;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--ink);
  font-weight: 900;
}

.progress-track {
  height: 4px;
  background: rgba(19, 33, 38, 0.08);
}

.progress-track span {
  display: block;
  width: 0%;
  height: 100%;
  background: linear-gradient(90deg, var(--teal), var(--gold), var(--coral), var(--violet), var(--rose));
  transition: width 250ms ease;
}

.terms-panel {
  position: fixed;
  z-index: 70;
  top: calc(var(--header-height) + 18px);
  right: 16px;
  width: min(440px, calc(100% - 32px));
  max-height: calc(100svh - var(--header-height) - 36px);
  overflow: auto;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface-strong);
  box-shadow: var(--shadow);
}

.terms-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 12px;
}

.terms-header h2 {
  margin: 0;
  font-size: 1.25rem;
}

.terms-list {
  display: grid;
  gap: 10px;
}

.term-item {
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fffaf1;
}

.term-item strong {
  display: block;
  margin-bottom: 4px;
}

.term-item p {
  margin: 0;
  font-size: 0.92rem;
}

.mini-lab {
  width: min(1220px, calc(100% - 32px));
  margin: 0 auto;
  padding: 42px 0 64px;
}

.lab-window {
  display: none;
}

.lab-window.is-active {
  display: block;
}

.window-grid,
.timeline-layout {
  display: grid;
  grid-template-columns: minmax(320px, 0.9fr) minmax(420px, 1.1fr);
  gap: 28px;
  align-items: center;
}

.copy-column {
  min-width: 0;
}

.eyebrow {
  margin-bottom: 10px;
  color: var(--teal-dark);
  font-size: 0.78rem;
  font-weight: 900;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.lead {
  max-width: 740px;
  margin-bottom: 26px;
  color: #40514d;
  font-size: clamp(1.05rem, 1.6vw, 1.28rem);
}

.capability-path,
.era-ribbon {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 18px;
}

.path-step,
.era-step {
  min-height: 36px;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 11px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(255, 253, 248, 0.72);
  color: var(--muted);
  font-size: 0.84rem;
  font-weight: 850;
}

.path-step::before,
.era-step::before {
  content: "";
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--line);
}

.path-step.is-complete,
.era-step.is-complete {
  color: var(--ink);
}

.path-step.is-complete::before,
.era-step.is-complete::before {
  background: var(--teal);
}

.path-step.is-active,
.era-step.is-active {
  border-color: rgba(216, 105, 79, 0.6);
  background: rgba(216, 105, 79, 0.11);
  color: #6f2c21;
}

.path-step.is-active::before,
.era-step.is-active::before {
  background: var(--coral);
}

.campus-stage {
  min-width: 0;
  display: grid;
  gap: 16px;
}

.campus-art {
  width: 100%;
  max-height: 390px;
  display: block;
  object-fit: contain;
  filter: drop-shadow(0 18px 34px rgba(19, 33, 38, 0.12));
}

.scenario-console,
.definition-card,
.hierarchy-card,
.slider-card,
.milestone-card,
.timeline-side {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow);
}

.scenario-console {
  padding: 18px;
}

.scenario-console span,
.definition-card span,
.milestone-card span {
  display: block;
  margin-bottom: 8px;
  color: var(--coral);
  font-size: 0.78rem;
  font-weight: 900;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.scenario-console h2,
.definition-card h2,
.milestone-card h2 {
  margin-bottom: 8px;
}

.scenario-console p,
.definition-card p,
.milestone-card p {
  margin-bottom: 0;
}

.mini-output {
  min-height: 46px;
  margin-top: 14px;
  padding: 11px 12px;
  border-left: 4px solid var(--teal);
  background: #eef7f2;
  color: var(--teal-dark);
  font-weight: 850;
}

.concept-controls {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 10px;
  margin: 30px 0 20px;
}

.concept-button {
  min-height: 110px;
  padding: 14px;
  display: grid;
  align-content: space-between;
  gap: 12px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(255, 253, 248, 0.72);
  color: var(--ink);
  text-align: left;
  transition: transform 160ms ease, border-color 160ms ease, background 160ms ease;
}

.concept-button:hover {
  transform: translateY(-2px);
}

.concept-button.is-active {
  border-color: rgba(47, 123, 117, 0.75);
  background: #edf7f3;
}

.concept-button small {
  color: var(--muted);
  font-size: 0.76rem;
  font-weight: 900;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.concept-button strong {
  font-size: 1.02rem;
  line-height: 1.15;
}

.concept-glyph {
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--ink);
  color: #fff;
  font-weight: 900;
}

.understanding-grid {
  display: grid;
  grid-template-columns: minmax(280px, 0.9fr) minmax(360px, 1.1fr);
  gap: 18px;
  align-items: stretch;
}

.definition-card,
.hierarchy-card {
  padding: 22px;
}

.definition-card h2 {
  font-size: clamp(1.35rem, 2.1vw, 2rem);
}

.hierarchy-card {
  display: grid;
  gap: 14px;
}

.hierarchy-map {
  min-height: 360px;
  display: grid;
  place-items: center;
}

.ring {
  display: grid;
  place-items: center;
  position: relative;
  border: 2px solid var(--line);
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.72);
  transition: border-color 220ms ease, background 220ms ease, box-shadow 220ms ease;
}

.ring > span {
  position: absolute;
  top: 14px;
  left: 50%;
  transform: translateX(-50%);
  width: max-content;
  max-width: 80%;
  color: var(--ink);
  font-size: 0.82rem;
  font-weight: 900;
  text-align: center;
}

.ring-ai {
  width: min(100%, 350px);
  aspect-ratio: 1;
  border-color: rgba(47, 123, 117, 0.52);
}

.ring-ml {
  width: 75%;
  aspect-ratio: 1;
  border-color: rgba(229, 184, 75, 0.62);
}

.ring-dl {
  width: 68%;
  aspect-ratio: 1;
  border-color: rgba(216, 105, 79, 0.6);
}

.genai-chip,
.llm-chip {
  position: absolute;
  display: grid;
  place-items: center;
  min-width: 116px;
  min-height: 38px;
  padding: 8px 10px;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: var(--surface-strong);
  color: var(--ink);
  font-weight: 900;
  text-align: center;
  transition: transform 220ms ease, background 220ms ease, border-color 220ms ease;
}

.genai-chip {
  bottom: 46px;
  left: 18px;
}

.llm-chip {
  right: 20px;
  bottom: 96px;
}

[data-focus="ai"] .ring-ai,
[data-focus="ml"] .ring-ml,
[data-focus="dl"] .ring-dl {
  border-color: var(--teal);
  background: rgba(47, 123, 117, 0.09);
  box-shadow: inset 0 0 0 8px rgba(47, 123, 117, 0.08);
}

[data-focus="genai"] .genai-chip,
[data-focus="llm"] .llm-chip {
  border-color: rgba(92, 107, 192, 0.68);
  background: #eef0ff;
  transform: translateY(-4px);
}

.quiz-section {
  margin-top: 30px;
  padding-top: 28px;
  border-top: 1px solid var(--line);
}

.quiz-section > div:first-child {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 18px;
  margin-bottom: 14px;
}

.quiz-section h2 {
  margin-bottom: 0;
}

.quiz-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 10px;
}

.quiz-card {
  min-height: 158px;
  padding: 14px;
  display: grid;
  align-content: space-between;
  gap: 12px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(255, 253, 248, 0.72);
  color: var(--ink);
  text-align: left;
}

.quiz-card strong {
  line-height: 1.2;
}

.quiz-answer {
  min-height: 44px;
  display: grid;
  align-content: center;
  padding-top: 10px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.86rem;
  font-weight: 850;
}

.quiz-card.is-revealed {
  border-color: rgba(47, 123, 117, 0.65);
  background: #edf7f3;
}

.quiz-card.is-revealed .quiz-answer {
  color: var(--teal-dark);
}

.timeline-layout {
  grid-template-columns: minmax(0, 1fr) 340px;
  align-items: start;
}

.timeline-main {
  min-width: 0;
}

.slider-card {
  margin-top: 24px;
  padding: 18px;
}

.timeline-slider-label {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 12px;
  color: var(--muted);
  font-weight: 900;
}

.timeline-slider-label strong {
  color: var(--ink);
  font-size: 1.5rem;
}

input[type="range"] {
  width: 100%;
  accent-color: var(--teal);
}

.timeline-track {
  margin-top: 18px;
  display: grid;
  grid-template-columns: repeat(13, minmax(0, 1fr));
  gap: 5px;
}

.timeline-dot {
  min-height: 54px;
  padding: 5px 2px;
  display: grid;
  justify-items: center;
  align-content: start;
  gap: 6px;
  border: 0;
  background: transparent;
  color: var(--muted);
  font-size: 0.68rem;
  font-weight: 850;
}

.timeline-dot::before {
  content: "";
  width: 14px;
  height: 14px;
  border: 2px solid var(--line);
  border-radius: 50%;
  background: var(--surface-strong);
}

.timeline-dot.is-complete::before {
  border-color: var(--teal);
  background: var(--teal);
}

.timeline-dot.is-active {
  color: var(--ink);
}

.timeline-dot.is-active::before {
  border-color: var(--coral);
  background: var(--coral);
  box-shadow: 0 0 0 5px rgba(216, 105, 79, 0.18);
}

.milestone-card {
  margin-top: 18px;
  padding: 22px;
}

.milestone-card h2 {
  font-size: clamp(1.7rem, 3vw, 2.65rem);
}

.capability-badge {
  display: inline-flex;
  align-items: center;
  min-height: 38px;
  margin-top: 16px;
  padding: 8px 11px;
  border-left: 4px solid var(--violet);
  background: #eef0ff;
  color: #2e356f;
  font-weight: 850;
}

.timeline-side {
  position: sticky;
  top: calc(var(--header-height) + 28px);
  padding: 18px;
}

.timeline-side h2 {
  margin-bottom: 14px;
  font-size: 1.25rem;
}

.compact-family {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
}

.compact-family button {
  min-height: 66px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(255, 253, 248, 0.74);
  color: var(--muted);
  font-weight: 900;
}

.compact-family button:last-child {
  grid-column: 1 / -1;
}

.compact-family button.is-active {
  border-color: rgba(92, 107, 192, 0.72);
  background: #eef0ff;
  color: #2e356f;
}

.timeline-side p {
  margin: 16px 0 0;
}

@media (max-width: 1060px) {
  .header-inner {
    grid-template-columns: 1fr auto;
  }

  .window-tabs {
    grid-column: 1 / -1;
    grid-row: 2;
    width: 100%;
    margin-bottom: 12px;
  }

  .window-grid,
  .timeline-layout {
    grid-template-columns: 1fr;
  }

  .timeline-side {
    position: static;
  }

  .concept-controls,
  .quiz-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (max-width: 760px) {
  body {
    font-size: 15px;
  }

  .mini-lab {
    width: min(100% - 24px, 1220px);
    padding-top: 26px;
  }

  .header-inner {
    width: min(100% - 24px, 1220px);
    gap: 12px;
  }

  .brand span:last-child {
    max-width: 180px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .concept-controls,
  .quiz-grid,
  .understanding-grid {
    grid-template-columns: 1fr;
  }

  .concept-button,
  .quiz-card {
    min-height: auto;
  }

  .hierarchy-map {
    min-height: 300px;
  }

  .ring-ai {
    width: min(100%, 294px);
  }

  .ring > span {
    font-size: 0.72rem;
  }

  .genai-chip,
  .llm-chip {
    min-width: 92px;
    font-size: 0.78rem;
  }

  .genai-chip {
    bottom: 36px;
    left: 10px;
  }

  .llm-chip {
    right: 12px;
    bottom: 82px;
  }

  .timeline-track {
    grid-template-columns: repeat(7, minmax(0, 1fr));
  }
}

@media (max-width: 460px) {
  .window-tabs {
    grid-template-columns: 1fr;
  }

  .header-actions {
    gap: 6px;
  }

  .icon-button {
    width: 40px;
    height: 40px;
  }

  .campus-art {
    max-height: 300px;
  }

  .compact-family {
    grid-template-columns: 1fr;
  }

  .compact-family button:last-child {
    grid-column: auto;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.001ms !important;
    animation-duration: 0.001ms !important;
  }
}