.toc {
  --font-sans: 'DM Sans', system-ui, -apple-system, sans-serif;
  --space-xxs: 4px; --space-xs: 8px; --space-sm: 12px; --space-md: 16px; --space-lg: 24px; --space-xxl: 40px;
  --radius-xs: 8px; --radius-md: 16px; --radius-full: 360px;
  --border-sm: 1px; --border-md: 2px;
  --type-tiny: 500 11px/1.5 var(--font-sans);
  --type-small: 500 12px/1.5 var(--font-sans);
  --type-body-regular: 400 16px/1.5 var(--font-sans);
  --ls-small: -0.02em; --ls-body: -0.015em;
  --surface-inset: #232322;
  --border-subtle: #3E3E3A;
  --border-default: #3E3E3A;
  --text-primary: #FFFFFF;
  --text-secondary: #D7D6CE;
  --text-muted: #7C7B74;
  --text-faint: #7C7B74;
  --text-on-primary: #FAFAF9;
  --text-on-accent: #292927;
  --s-100: #FF6A5F;
  --p-80: #657671;
  margin: 0 0 44px;
}
.toc li { margin: 0; }
.toc {
  --toc-dot: 28px;
  background: var(--surface-inset);
  border: var(--border-sm) solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: var(--space-lg);
  color: var(--text-secondary);
  font-family: var(--font-sans);
}
.toc__head {
  display: flex; flex-wrap: wrap; justify-content: space-between; align-items: baseline;
  gap: var(--space-xs) var(--space-sm);
  padding-bottom: var(--space-md);
  margin-bottom: var(--space-md);
  border-bottom: var(--border-sm) solid var(--border-subtle);
}
.toc__label {
  margin: 0;
  font: var(--type-tiny); font-weight: 700;
  letter-spacing: 0.14em; text-transform: uppercase;
  color: var(--text-muted);
}
.toc__meta {
  font: var(--type-small); letter-spacing: var(--ls-small);
  color: var(--text-faint);
  font-variant-numeric: tabular-nums;
}
.toc__body {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.5fr);
  gap: var(--space-lg) var(--space-xxl);
}
.toc__side { display: flex; flex-direction: column; gap: var(--space-lg); }
.toc__group { display: flex; flex-direction: column; gap: var(--space-xs); min-width: 0; }
.toc__list,
.toc__rail { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; }
.toc__link {
  display: flex; align-items: center; gap: var(--space-sm);
  padding: 6px var(--space-xs);
  margin-left: calc(-1 * var(--space-xs));
  border-radius: var(--radius-xs);
  color: var(--text-secondary);
  text-decoration: none;
  font: var(--type-body-regular); letter-spacing: var(--ls-body); line-height: 1.35;
  transition: background-color .15s, color .15s;
}
.toc__link:hover { background: color-mix(in srgb, var(--s-100) 8%, transparent); color: var(--text-primary); }
.toc__link:focus-visible { outline: var(--border-md) solid var(--s-100); outline-offset: 2px; }
.toc__link.is-current { color: var(--text-primary); }
.toc__rail > li { position: relative; }
.toc__rail > li::before {
  content: ""; position: absolute;
  left: calc(var(--toc-dot) / 2 - 0.5px);
  top: 0; bottom: 0;
  width: var(--border-sm);
  background: var(--border-default);
}
.toc__rail > li:first-child::before,
.toc__rail > .toc__phase:first-child + li::before { top: 50%; }
.toc__rail > li:last-child::before { bottom: 50%; }
.toc__rail > .toc__phase:first-child::before { display: none; }
.toc__rail .toc__link { margin-left: 0; padding: 5px var(--space-xs) 5px 0; }
.toc__rail .toc__link:hover { background: transparent; }
.toc__phase {
  padding: var(--space-sm) 0 var(--space-xxs) calc(var(--toc-dot) + var(--space-sm));
  font: var(--type-tiny); letter-spacing: 0.04em;
  color: var(--text-faint);
}
.toc__phase:first-child { padding-top: 0; }
.toc__dot {
  position: relative; z-index: 1; flex: none;
  width: var(--toc-dot); height: var(--toc-dot);
  display: grid; place-items: center;
  border-radius: var(--radius-full);
  border: var(--border-sm) solid var(--border-default);
  background: var(--surface-inset);
  color: var(--text-muted);
  font: var(--type-tiny); font-variant-numeric: tabular-nums;
  transition: background-color .15s, border-color .15s, color .15s;
}
.toc__link:hover .toc__dot { border-color: var(--s-100); color: var(--s-100); }
.toc__link.is-done .toc__dot { background: var(--p-80); border-color: var(--p-80); color: var(--text-on-primary); }
.toc__link.is-current .toc__dot { background: var(--s-100); border-color: var(--s-100); color: var(--text-on-accent); }
.toc--flat .toc__body { grid-template-columns: minmax(0, 1fr); }
@media (max-width: 640px) {
  .toc { padding: var(--space-md); }
  .toc__body { grid-template-columns: minmax(0, 1fr); }
  .toc__side { display: contents; }
  .toc__group--closing { order: 1; }
}
@media (prefers-reduced-motion: reduce) {
  .toc__link, .toc__dot { transition: none; }
}