/* Public chapter catalogue. Shared cards and the Bac offer keep their own styles. */
body[data-chapter-navigation] {
  --chapter-green: #86efac;
  --chapter-green-bg: rgb(34 197 94 / 9%);
  --chapter-picker-bg: #121a29;
}

body[data-chapter-navigation][data-theme="light"] {
  --chapter-green: #166534;
  --chapter-green-bg: rgb(22 101 52 / 7%);
  --chapter-picker-bg: #fff;
}

[data-chapter-navigation] .main-stage {
  padding-inline: clamp(20px, 2.5vw, 40px);
  gap: 32px;
}

.chapter-heading {
  margin: 2px 0 28px;
  text-align: center;
}

.chapter-heading__eyebrow {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 8px;
  margin: 0 0 10px;
  color: var(--chapter-green);
  font-size: 0.86rem;
  font-weight: 650;
}

.chapter-heading__wave {
  display: inline-block;
  font-size: 1.45rem;
  line-height: 1;
  transform-origin: 70% 70%;
  animation: chapter-wave 1.8s ease-in-out 0.2s 2;
}

@keyframes chapter-wave {
  0%,
  60%,
  100% { transform: rotate(0deg); }

  10%,
  30% { transform: rotate(14deg); }
  20% { transform: rotate(-8deg); }
  40% { transform: rotate(-4deg); }
  50% { transform: rotate(10deg); }
}

[data-chapter-navigation] .chapter-heading h1 {
  font-size: clamp(1.65rem, 2.8vw, 2.65rem);
  text-align: center;
  text-wrap: balance;
}

.chapter-toolbar {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  gap: 16px 24px;
  margin-bottom: 24px;
}

.chapter-resume {
  display: flex;
  align-items: center;
  gap: 12px;
  flex: 1 1 20rem;
  padding: 14px 18px;
  border: 1px solid var(--app-border-strong);
  border-radius: 16px;
  background: var(--dashboard-card-bg);
  color: var(--app-text);
  text-decoration: none;
}

.chapter-resume[hidden] { display: none; }
.chapter-resume svg { width: 24px; height: 24px; flex: 0 0 24px; color: var(--chapter-green); }
.chapter-resume__label { display: block; margin-bottom: 4px; color: var(--app-text-soft, var(--app-muted)); font-size: 0.8rem; }
.chapter-resume strong { font-size: 0.95rem; line-height: 1.4; }
.chapter-resume:hover { border-color: var(--chapter-green); }
.chapter-resume:focus-visible { outline: 3px solid var(--chapter-green); outline-offset: 3px; }

.chapter-picker {
  flex: 0 1 21rem;
  width: 100%;
  min-width: 0;
  border: 1px solid var(--app-border-strong);
  border-radius: 16px;
  background: var(--dashboard-card-bg);
  color: var(--app-text);
}

.chapter-picker__toggle {
  display: flex;
  align-items: center;
  gap: 12px;
  min-height: 56px;
  padding: 12px 18px;
  border-radius: 16px;
  cursor: pointer;
  font-size: 0.94rem;
  font-weight: 700;
  list-style: none;
}

.chapter-picker__toggle::-webkit-details-marker { display: none; }
.chapter-picker__toggle:hover { background: var(--glass-weak-hover); }

.chapter-picker__count {
  margin-left: auto;
  color: var(--app-text-soft, var(--app-muted));
  font-size: 0.78rem;
  font-weight: 500;
  white-space: nowrap;
}

.chapter-picker__chevron {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  transition: transform 0.18s ease;
}

.chapter-picker[open] .chapter-picker__chevron { transform: rotate(180deg); }

.chapter-picker__list {
  display: grid;
  gap: 4px;
  max-height: min(22rem, 50dvh);
  padding: 8px;
  overflow-y: auto;
  overscroll-behavior: contain;
  scrollbar-width: thin;
  scrollbar-color: var(--app-border-strong) transparent;
  border-top: 1px solid var(--app-border);
  border-radius: 0 0 16px 16px;
  background: var(--chapter-picker-bg);
}

.chapter-picker__link {
  display: flex;
  align-items: center;
  gap: 12px;
  min-height: 48px;
  padding: 8px 10px;
  border-radius: 10px;
  color: var(--app-text);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 550;
  line-height: 1.4;
}

.chapter-picker__number {
  display: grid;
  place-items: center;
  flex: 0 0 30px;
  height: 30px;
  border-radius: 9px;
  background: var(--chapter-green-bg);
  color: var(--chapter-green);
  font-size: 0.75rem;
  font-weight: 800;
  font-variant-numeric: tabular-nums;
}

.chapter-picker__link:hover { background: var(--chapter-green-bg); }

:is(.chapter-picker__toggle, .chapter-picker__link, .chapter-grid .data-card):focus-visible {
  outline: 2px solid var(--chapter-green);
  outline-offset: 3px;
}

.chapter-grid {
  /* Up to three columns, based on the space left by the two sidebars. */
  grid-template-columns: repeat(auto-fit, minmax(min(100%, max(236px, calc((100% - 40px) / 3))), 1fr));
  gap: 20px;
}

.chapter-grid .data-card {
  min-height: 218px;
  padding: 22px;
  justify-content: flex-start;
}

.chapter-grid .card-header { gap: 8px; }

.chapter-grid .card-badge {
  color: var(--chapter-green);
  background: var(--chapter-green-bg);
  border-color: color-mix(in srgb, var(--chapter-green) 24%, transparent);
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.025em;
}

.chapter-grid .card-content h3 {
  margin: 0;
  font-size: 1.08rem;
  line-height: 1.4;
  overflow-wrap: break-word;
}

.chapter-motif {
  --motif-hover-ink: color-mix(in srgb, var(--theme-color) 82%, #fff);

  display: grid;
  place-items: center;
  align-self: flex-end;
  width: 90px;
  height: 58px;
  flex-shrink: 0;
  margin-top: auto;
  padding: 6px;
  border-radius: 14px;
  background: color-mix(in srgb, var(--theme-color) 7%, transparent);
  border: 1px solid color-mix(in srgb, var(--theme-color) 16%, transparent);
  color: var(--theme-color);
  transform-origin: bottom right;
  transition:
    transform 180ms ease,
    color 180ms ease,
    background-color 180ms ease,
    border-color 180ms ease,
    box-shadow 180ms ease;
}

.chapter-motif--formula {
  width: max-content;
  min-width: 90px;
  max-width: 100%;
  padding-inline: 12px;
}

.chapter-grid .card-content { margin-bottom: 18px; }
.chapter-motif svg { width: 100%; height: 100%; overflow: visible; }

.chapter-motif__formula {
  font-family: "Cambria Math", "STIX Two Math", Georgia, serif;
  font-size: 1.5rem;
  font-style: italic;
  white-space: nowrap;
}

.chapter-motif__formula--long { font-size: 1.14rem; }

[data-theme="light"] .chapter-motif {
  --motif-hover-ink: color-mix(in srgb, var(--theme-color) 76%, #0f172a);

  color: color-mix(in srgb, var(--theme-color) 68%, #0f172a);
}

.chapter-grid .data-card:focus-visible .chapter-motif {
  color: var(--motif-hover-ink);
  background-color: color-mix(in srgb, var(--theme-color) 14%, transparent);
  border-color: color-mix(in srgb, var(--theme-color) 36%, transparent);
  box-shadow: 0 0 16px color-mix(in srgb, var(--theme-color) 16%, transparent);
  transform: scale(1.045);
}

@media (hover: hover) {
  .chapter-grid .data-card:hover { transform: translateY(-4px); }

  .chapter-grid .data-card:hover .chapter-motif {
    color: var(--motif-hover-ink);
    background-color: color-mix(in srgb, var(--theme-color) 14%, transparent);
    border-color: color-mix(in srgb, var(--theme-color) 36%, transparent);
    box-shadow: 0 0 16px color-mix(in srgb, var(--theme-color) 16%, transparent);
    transform: scale(1.045);
  }
}

/* Match the shared rail's hiding breakpoint, including the tablet interval. */
@media (max-width: 1024px) {
  [data-chapter-navigation] .app-layout { display: block; }
  [data-chapter-navigation] .main-stage { height: 100dvh; }
}

@media (max-width: 36rem) {
  [data-chapter-navigation] .main-stage { padding-inline: 20px; }
  .chapter-grid { gap: 16px; }
  .chapter-grid .data-card { min-height: 202px; }
  .chapter-heading { margin-bottom: 24px; }
  .chapter-picker__toggle { padding-inline: 14px; gap: 8px; }
}

@media (prefers-reduced-motion: reduce) {
  .chapter-heading__wave { animation: none; }

  .chapter-picker__chevron,
  .chapter-grid .data-card { transition: none; }

  .chapter-motif { transition: none; }

  .chapter-grid .data-card:is(:hover, :focus-visible) .chapter-motif {
    transform: none;
  }
}