.hidden {
  display: none !important;
}

/* Econometrics series: wide layout + left nav (scoped to .series-page) */
.series-page {
  max-width: 1040px;
}

.series-layout {
  display: flex;
  align-items: flex-start;
  gap: 1.75rem;
  margin-top: 1.5rem;
}

.series-nav {
  flex: 0 0 220px;
  position: sticky;
  top: 1rem;
  align-self: flex-start;
  max-height: calc(100vh - 2rem);
  overflow-y: auto;
  padding-right: 0.35rem;
  border-right: 1px solid var(--border);
}

.series-nav-title {
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-secondary);
  margin: 0 0 0.5rem 0.15rem;
}

.series-nav ol {
  list-style: none;
  padding: 0;
  margin: 0;
}

.series-nav li {
  margin-bottom: 0.15rem;
}

.series-nav a {
  display: block;
  padding: 0.4rem 0.5rem;
  border-radius: 4px;
  font-size: 0.88rem;
  line-height: 1.35;
  color: var(--text-secondary);
  text-decoration: none;
}

.series-nav a:hover {
  color: var(--text);
  background: rgba(0, 0, 0, 0.04);
}

.series-nav a.active {
  color: var(--text);
  font-weight: 600;
  background: var(--code-bg);
}

.series-main {
  flex: 1;
  min-width: 0;
}

.series-article {
  padding-bottom: 3rem;
}

/* Intuition blockquotes: accent colour, readable body */
.series-article .series-callout--intuition {
  font-style: normal;
  color: var(--text);
  border: 1px solid rgba(217, 119, 6, 0.45);
  border-left: 4px solid #d97706;
  background: rgba(217, 119, 6, 0.09);
  padding: 0.9rem 1rem 0.95rem 1.05rem;
  margin: 1.35rem 0;
  border-radius: 6px;
}

.series-article .series-callout--intuition > p:first-child > strong:first-child {
  color: #d97706;
  font-weight: 700;
}

.series-article .series-callout--intuition p {
  color: var(--text);
}

.series-article .series-callout--intuition p:last-child {
  margin-bottom: 0;
}

/* Example sections: collapsible callout (<details>) */
.series-article details.series-callout--example {
  font-style: normal;
  color: var(--text);
  margin: 1.5rem 0;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: rgba(100, 116, 139, 0.035);
  box-shadow: 0 1px 2px rgba(26, 26, 26, 0.03);
  overflow: hidden;
}

.series-article details.series-callout--example > summary.series-example-summary {
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  gap: 0.55rem;
  margin: 0;
  padding: 0.65rem 1rem 0.65rem 1.2rem;
  min-height: 2.75rem;
  box-sizing: border-box;
  user-select: none;
  position: relative;
  background: rgba(100, 116, 139, 0.045);
}

.series-article details.series-callout--example > summary.series-example-summary::after {
  content: "";
  position: absolute;
  left: 0.65rem;
  top: 50%;
  transform: translateY(-50%);
  width: 3px;
  height: 1.1rem;
  border-radius: 999px;
  background: rgba(100, 116, 139, 0.45);
  pointer-events: none;
}

.series-article details.series-callout--example > summary::-webkit-details-marker {
  display: none;
}

.series-article details.series-callout--example > summary::before {
  content: "";
  flex-shrink: 0;
  width: 0.42em;
  height: 0.42em;
  border-right: 2px solid rgba(100, 116, 139, 0.5);
  border-bottom: 2px solid rgba(100, 116, 139, 0.5);
  transform: rotate(-45deg);
  transition: transform 0.18s ease;
}

.series-article details.series-callout--example[open] > summary::before {
  transform: rotate(45deg);
}

.series-article details.series-callout--example .series-example-summary-label {
  font-size: 0.88rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  color: var(--text-secondary);
  flex: 1;
  min-width: 0;
  line-height: 1.3;
}

.series-article details.series-callout--example .series-example-body > h2:first-child,
.series-article details.series-callout--example .series-example-body > h3:first-child {
  margin-top: 0;
  margin-bottom: 0.65rem;
  font-size: 1.08rem;
  font-weight: 600;
  color: var(--text);
}

.series-article details.series-callout--example .series-example-body > p:first-child {
  margin-top: 0;
}

.series-article details.series-callout--example .series-example-body {
  margin: 0;
  padding: 0.85rem 1rem 1rem 1rem;
  border-top: 1px solid rgba(100, 116, 139, 0.12);
  background: rgba(100, 116, 139, 0.028);
}

.series-article details.series-callout--example .series-example-body > *:last-child {
  margin-bottom: 0;
}

.series-article img {
  max-width: 100%;
  height: auto;
  display: block;
  margin: 1.25rem auto;
}

.series-loading {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 1rem;
}

.series-error {
  color: #a33;
  font-size: 0.9rem;
}

@media (max-width: 720px) {
  .series-layout {
    flex-direction: column;
    gap: 1rem;
  }

  .series-nav {
    position: relative;
    top: auto;
    max-height: none;
    width: 100%;
    flex: none;
    border-right: none;
    border-bottom: 1px solid var(--border);
    padding-bottom: 0.75rem;
    padding-right: 0;
  }

  .series-nav ol {
    display: flex;
    flex-direction: column;
    gap: 0.1rem;
  }
}

/* ─── Interactive widgets ─── */
.econ-widget {
  margin: 1.75rem 0 2rem;
}

.econ-widget__poster {
  text-align: center;
}

.econ-widget__poster img {
  max-width: 100%;
  height: auto;
  display: block;
  margin: 0 auto;
  border-radius: 4px;
}

.econ-widget__poster-actions {
  margin-top: 0.65rem;
  display: flex;
  justify-content: center;
}

.econ-widget__activate {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-secondary);
  padding: 0.32rem 0.9rem;
  font-size: 0.82rem;
  border-radius: 999px;
  cursor: pointer;
  font-family: inherit;
  letter-spacing: 0.02em;
  transition: color 0.15s ease, border-color 0.15s ease, background 0.15s ease;
}

.econ-widget__activate:hover:not(:disabled) {
  color: #D97706;
  border-color: rgba(217, 119, 6, 0.55);
  background: rgba(217, 119, 6, 0.05);
}

.econ-widget__activate:disabled {
  opacity: 0.55;
  cursor: default;
}

.econ-widget--active {
  padding: 0;
}

.econ-widget__scene {
  width: 100%;
  height: 420px;
  margin: 0 auto;
}

.econ-widget__controls {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1.4rem;
  padding: 0.75rem 0 0.55rem;
  border-top: 1px solid var(--border);
  margin-top: 0.25rem;
}

.econ-widget__slider {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 0.85rem;
  color: var(--text-secondary);
  letter-spacing: 0.005em;
}

.econ-widget__slider-label {
  white-space: nowrap;
}

.econ-widget__slider input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 130px;
  height: 3px;
  background: var(--border);
  border-radius: 999px;
  outline: none;
  accent-color: #D97706;
  cursor: pointer;
}

.econ-widget__slider input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: #D97706;
  border: 2px solid var(--bg);
  box-shadow: 0 0 0 1px rgba(217, 119, 6, 0.35);
  cursor: pointer;
  transition: transform 0.12s ease;
}

.econ-widget__slider input[type="range"]::-webkit-slider-thumb:hover {
  transform: scale(1.12);
}

.econ-widget__slider input[type="range"]::-moz-range-thumb {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: #D97706;
  border: 2px solid var(--bg);
  box-shadow: 0 0 0 1px rgba(217, 119, 6, 0.35);
  cursor: pointer;
}

.econ-widget__reset {
  margin-left: auto;
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-secondary);
  padding: 0.25rem 0.75rem;
  font-size: 0.78rem;
  border-radius: 4px;
  cursor: pointer;
  font-family: inherit;
  letter-spacing: 0.01em;
  transition: color 0.15s ease, border-color 0.15s ease;
}

.econ-widget__reset:hover {
  color: var(--text);
  border-color: var(--text-secondary);
}

.econ-widget__readout {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  padding: 0.35rem 0 0.1rem;
  font-family: 'SF Mono', 'Fira Code', 'Consolas', 'Monaco', monospace;
  font-size: 0.78rem;
  color: var(--text-secondary);
}

.econ-widget__readout-row {
  display: inline-flex;
  align-items: baseline;
  gap: 0.5rem;
}

.econ-widget__readout-label {
  color: var(--text-secondary);
  opacity: 0.85;
}

.econ-widget__readout-value {
  color: var(--text);
  font-variant-numeric: tabular-nums;
}

.econ-widget__readout sub {
  font-size: 0.8em;
}

.econ-widget__readout-row .katex {
  font-size: 0.95em;
}

/* Legend: small coloured swatches + KaTeX math labels, sitting under scene */
.econ-widget__legend {
  display: flex;
  flex-wrap: wrap;
  gap: 1.1rem 1.4rem;
  align-items: center;
  justify-content: center;
  padding: 0.55rem 0 0.35rem;
  margin: 0;
  font-size: 0.82rem;
  color: var(--text-secondary);
}

.econ-widget__legend-item {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  line-height: 1;
}

.econ-widget__legend-swatch {
  display: inline-block;
  width: 1.6rem;
  height: 2px;
  background: var(--swatch-color, currentColor);
  border-radius: 999px;
  flex-shrink: 0;
}

.econ-widget__legend-item--dashed .econ-widget__legend-swatch {
  background: none;
  border-top: 2px dashed var(--swatch-color, currentColor);
  height: 0;
}

.econ-widget__legend-item--dotted .econ-widget__legend-swatch {
  background: none;
  border-top: 2px dotted var(--swatch-color, currentColor);
  height: 0;
}

.econ-widget__legend-label {
  color: var(--text);
  line-height: 1;
}

.econ-widget__legend-label .katex {
  font-size: 1em;
}

.econ-widget__caption {
  font-size: 0.85rem;
  color: var(--text-secondary);
  font-style: italic;
  margin: 0.7rem 0 0;
  line-height: 1.55;
  text-align: center;
}

.econ-widget__error {
  font-size: 0.85rem;
  color: #a33;
  margin: 0.5rem 0 0;
  text-align: center;
}

@media (max-width: 720px) {
  .econ-widget__scene {
    height: 340px;
  }

  .econ-widget__controls {
    gap: 0.9rem;
  }

  .econ-widget__slider input[type="range"] {
    width: 110px;
  }

  .econ-widget__reset {
    margin-left: 0;
    order: 10;
  }
}