.learn-index {
  --ink: #183d33;
  --muted: #53645b;
  --teal: #185c48;
  --paper: #f6f3eb;
  --line: #ccd2c6;
  background: var(--paper);
  color: var(--ink);
}
.learn-index [hidden] {
  display: none !important;
}
.learn-index :is(button, input, select, summary, a):focus-visible {
  outline: 3px solid #a44806;
  outline-offset: 4px;
}
.learn-index header,
.learn-index main,
.learn-index footer {
  max-width: 1280px;
}
.learn-index header {
  align-items: center;
}
.learn-index header a {
  min-height: 48px;
  display: inline-flex;
  align-items: center;
}
.learn-index h1,
.learn-index h2,
.learn-index h3 {
  font-family: Georgia, 'Times New Roman', serif;
  font-weight: 500;
  letter-spacing: -0.025em;
}
.learn-index h1 {
  font-size: clamp(2.4rem, 5.4vw, 4.8rem);
  max-width: 1000px;
}
.learn-index h2 {
  font-size: clamp(1.8rem, 3vw, 2.6rem);
}
.learn-index .lead {
  color: var(--ink);
  font-size: clamp(1.15rem, 2vw, 1.5rem);
  max-width: 55ch;
}
.learn-index main > p:not(.lead) {
  max-width: 85ch;
}
.learn-index a {
  color: #145742;
}
.learn-index a:hover {
  color: #092e23;
}
.learn-index .button {
  background: #185c48;
  color: white;
  min-height: 48px;
  border-radius: 4px;
}
.learn-index .button:hover {
  background: #123f31;
  color: white;
}
.learn-index .tags {
  margin: 1.5rem 0 2rem;
}
.learn-index .tags span {
  border: 0;
  padding: 0 1.2rem 0 0;
  border-right: 1px solid var(--line);
  border-radius: 0;
}
.learn-index .tags span:last-child {
  border: 0;
}
.learning-paths {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  border: 1px solid var(--line);
  border-radius: 12px;
  overflow: hidden;
  margin: 2.5rem 0 3.5rem;
  background: #fffdf7;
}
.learning-paths > a {
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  text-decoration: none;
  border-top: 5px solid var(--path);
  color: var(--ink);
}
.learning-paths > a + a {
  border-left: 1px solid var(--line);
}
.learning-paths > a:hover {
  background: #edf1e7;
}
.learning-paths strong {
  font-size: 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.learning-paths strong span {
  font-size: 1.2rem;
}
.learning-paths > a > span:last-child {
  font-size: 0.94rem;
}
.path-number,
.group-heading > span {
  font-size: 0.8rem;
  letter-spacing: 0.07em;
  text-transform: uppercase;
}
.path-continuity {
  --path: #185c48;
  --tint: #e9f0e7;
}
.path-emt {
  --path: #8a501a;
  --tint: #f5ecdf;
}
.path-dynamics {
  --path: #64448c;
  --tint: #eee8f3;
}
.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 2rem;
  margin: 3rem 0 1.5rem;
}
.section-heading .eyebrow {
  margin: 0;
}
.section-heading h2 {
  margin: 0.3rem 0;
}
.section-heading > p {
  max-width: 50ch;
  font-size: 0.94rem;
  color: var(--muted);
  margin: 0;
}
.learn-search {
  background: #fffdf8;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 1.5rem;
}
.learn-search label {
  font-weight: 650;
  display: block;
}
.learn-search input {
  display: block;
  width: 100%;
  margin: 0.4rem 0 1rem;
  border: 1px solid #728276;
  border-radius: 5px;
  background: white;
  color: var(--ink);
  min-height: 52px;
  padding: 0.75rem;
  font: inherit;
}
.learn-search fieldset {
  border: 0;
  padding: 0;
  margin: 0;
}
.learn-search legend {
  font-weight: 650;
  margin-bottom: 0.5rem;
}
.path-filters {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}
.learn-index button,
.learn-index select {
  font: inherit;
  font-size: 1rem;
  min-height: 48px;
  border: 1px solid #738276;
  border-radius: 5px;
  color: var(--ink);
  background: #fffdf8;
  padding: 0.6rem 1rem;
  cursor: pointer;
}
.learn-index button:hover,
.learn-index select:hover {
  background: #e9eee4;
}
.learn-index button[aria-pressed='true'] {
  background: #185c48;
  border-color: #185c48;
  color: white;
}
.learn-index button:disabled {
  opacity: 0.6;
  cursor: default;
}
.search-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  margin-top: 1rem;
}
.search-footer p {
  margin: 0;
  color: var(--muted);
  font-size: 0.94rem;
}
.search-footer button {
  background: transparent;
  text-decoration: underline;
}
.learn-empty {
  padding: 2rem;
  border-left: 4px solid #8a501a;
  background: #f5ecdf;
}
.learning-group {
  scroll-margin-top: 1rem;
  margin: 2rem 0 3rem;
}
.group-heading {
  display: flex;
  align-items: center;
  gap: 1rem;
  border-bottom: 1px solid var(--line);
  padding-bottom: 0.7rem;
}
.group-heading h3 {
  font-size: 1.65rem;
  margin: 0;
  display: flex;
  align-items: center;
  gap: 0.65rem;
}
.group-heading h3:before {
  content: '';
  display: block;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--path);
}
.group-heading > span {
  margin-left: auto;
}
.learning-cards {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
  margin-top: 1.2rem;
}
.learning-card {
  min-width: 0;
  background: #fffdf8;
  border: 1px solid var(--line);
  border-top: 3px solid var(--path);
  border-radius: 9px;
  padding: 1.3rem;
  display: flex;
  flex-direction: column;
  position: relative;
}
.learning-card .eyebrow {
  color: var(--path);
  letter-spacing: 0.08em;
}
.learning-card h4 {
  font-size: 1.2rem;
  line-height: 1.35;
  margin: 0.55rem 0;
}
.learning-card h4 a {
  text-decoration: none;
  color: var(--ink);
}
.learning-card h4 a:hover {
  text-decoration: underline;
}
.learning-card p {
  font-size: 1rem;
  line-height: 1.65;
  margin: 0.6rem 0;
}
.learning-card .card-description {
  font-size: 1rem;
  color: var(--muted);
}
.card-links {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.4rem;
  flex-wrap: wrap;
  margin-top: auto;
  padding-top: 0.8rem;
  border-top: 1px solid var(--line);
}
.card-links a,
.explorer-links a {
  font-weight: 650;
  font-size: 0.9rem;
  min-height: 48px;
  display: inline-flex;
  align-items: center;
}
.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;
}
.learn-explorer {
  margin: 4rem 0;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
}
.model-picker {
  font-size: 0.9rem;
  font-weight: 650;
  min-width: 190px;
}
.model-picker select {
  display: block;
  width: 100%;
  margin-top: 0.4rem;
}
.model-explainer {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 2rem;
  background: #fffdf8;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 1.5rem;
  margin: 1.5rem 0;
}
.diagram-container {
  min-width: 0;
}
.diagram-container h3 {
  font-size: 1.7rem;
  line-height: 1.2;
  margin: 0.5rem 0 1.2rem;
}
.diagram-stage {
  perspective: 900px;
  background: radial-gradient(circle, var(--tint), transparent 70%);
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
}
.diagram-stage svg {
  display: block;
  width: 100%;
  transform: rotateX(12deg) rotateY(-8deg);
  transition: transform 0.35s ease;
  transform-origin: center;
}
.diagram-stage.is-rotated svg {
  transform: rotateX(8deg) rotateY(9deg);
}
.diagram-stage.static-view svg {
  transform: none;
  transition: none;
}
.diagram-stage .diagram-wire {
  stroke: var(--path);
  stroke-width: 3;
  fill: none;
}
.diagram-flow {
  stroke: var(--path);
  stroke-width: 6;
  fill: none;
  stroke-dasharray: 10 500;
  stroke-dashoffset: 0;
  opacity: 0;
}
.node-depth {
  fill: var(--tint);
  stroke: var(--path);
  stroke-width: 1.5;
}
.node-face {
  fill: #fffdf8;
  stroke: var(--path);
  stroke-width: 1.5;
}
.diagram-stage text {
  font:
    13px system-ui,
    sans-serif;
  fill: #183d33;
}
.diagram-summary {
  font-size: 0.94rem;
  color: var(--muted);
}
.diagram-controls {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}
.diagram-controls button {
  font-size: 0.9rem;
  padding: 0.5rem 0.7rem;
}
.flow-status {
  min-height: 2.8em;
}
.model-lenses {
  min-width: 0;
}
.model-lenses details {
  border-top: 1px solid var(--line);
  padding: 0.6rem 0;
}
.model-lenses summary {
  min-height: 48px;
  padding: 0.6rem 0.2rem;
  cursor: pointer;
  font-size: 1.05rem;
  font-weight: 650;
}
.lens-number {
  color: var(--path);
  font-size: 0.85rem;
  letter-spacing: 0.05em;
  margin-right: 0.5rem;
}
.model-lenses details p {
  font-size: 1rem;
  margin: 0.3rem 0 1rem;
}
.model-lenses details a {
  display: inline-block;
  margin-bottom: 1rem;
}
.explorer-links {
  border-top: 1px solid var(--line);
  display: flex;
  gap: 1rem;
  justify-content: space-between;
  flex-wrap: wrap;
  padding-top: 0.6rem;
}
.flow-playing .diagram-flow {
  opacity: 1;
  animation: learn-flow 3s linear 1 both;
}
.flow-paused .diagram-flow {
  animation-play-state: paused;
}
@keyframes learn-flow {
  0% {
    stroke-dashoffset: 500;
    opacity: 0;
  }
  10%,
  90% {
    opacity: 1;
  }
  100% {
    stroke-dashoffset: 0;
    opacity: 0;
  }
}
@media (max-width: 1000px) {
  .learning-cards {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .model-explainer {
    grid-template-columns: 1fr;
    gap: 1rem;
  }
  .diagram-stage {
    max-width: 640px;
  }
  .section-heading {
    align-items: start;
    gap: 1rem;
  }
  .section-heading > p {
    max-width: 38ch;
  }
  .learning-paths > a {
    padding: 1rem;
  }
  .learning-paths strong {
    font-size: 1.2rem;
  }
}
@media (max-width: 600px) {
  .learn-index main {
    padding-top: 2rem;
  }
  .learning-paths {
    grid-template-columns: 1fr;
    margin: 2rem 0;
  }
  .learning-paths > a {
    padding: 1rem 1.2rem;
  }
  .learning-paths > a + a {
    border-left: 0;
    border-top-width: 3px;
  }
  .learning-paths strong {
    font-size: 1.35rem;
  }
  .learning-cards {
    grid-template-columns: 1fr;
  }
  .section-heading {
    display: block;
  }
  .section-heading > p {
    margin-top: 1rem;
  }
  .learn-search,
  .model-explainer {
    padding: 1rem;
  }
  .path-filters button {
    flex: 1 1 42%;
  }
  .search-footer {
    align-items: start;
  }
  .group-heading {
    flex-wrap: wrap;
    gap: 0.3rem;
  }
  .group-heading > span {
    margin-left: 0;
    width: 100%;
  }
  .model-picker {
    display: block;
    margin-top: 1rem;
  }
  .model-lenses summary {
    font-size: 1rem;
  }
  .diagram-stage text {
    font-size: 14px;
  }
  .diagram-stage svg {
    transform: none;
  }
  .learn-index .tags {
    font-size: 1rem;
  }
  .learn-index figure {
    margin: 2rem 0;
  }
  .learn-index .tags span {
    padding-right: 0.6rem;
  }
  .card-links a {
    font-size: 0.94rem;
  }
}
@media (prefers-reduced-motion: reduce) {
  .diagram-stage svg {
    transition: none;
    transform: none !important;
  }
  .flow-playing .diagram-flow {
    animation: none;
    opacity: 0;
  }
}
@media (forced-colors: active) {
  .learning-paths > a,
  .learning-card,
  .learn-search,
  .model-explainer,
  .diagram-stage {
    border: 1px solid CanvasText;
  }
  .diagram-stage svg {
    transform: none;
  }
  .diagram-wire,
  .diagram-flow,
  .node-face,
  .node-depth {
    stroke: CanvasText !important;
  }
  .node-face,
  .node-depth {
    fill: Canvas !important;
  }
  .diagram-stage text {
    fill: CanvasText;
  }
  .learn-index button[aria-pressed='true'] {
    outline: 2px solid Highlight;
  }
  .group-heading h3:before {
    background: CanvasText;
  }
}
@media print {
  .learn-search,
  .learning-paths,
  .diagram-controls,
  .model-picker {
    display: none !important;
  }
  .learn-index [hidden].learning-card,
  .learn-index [hidden].learning-group,
  .learn-index [hidden].model-explainer {
    display: block !important;
  }
  .learning-cards {
    display: block;
  }
  .learning-card,
  .model-explainer {
    break-inside: avoid;
    margin: 1rem 0;
  }
  .model-explainer {
    display: block;
  }
  .model-lenses details > * {
    display: block !important;
  }
  .diagram-stage svg {
    transform: none !important;
  }
  .learn-index h1 {
    font-size: 25pt;
  }
}