.shell {
  display: grid;
  grid-template-columns: 1fr;
  min-block-size: 100dvh;
}

@media (min-width: 1024px) {
  .shell {
    grid-template-columns: var(--nav-w) minmax(0, 1fr);
  }
}

.main {
  min-inline-size: 0;   
}

.tlm-header {
  position: sticky;
  inset-block-start: 0;
  z-index: 60;
  display: flex;
  align-items: center;
  gap: var(--s-3);
  block-size: var(--header-h);
  padding-inline: var(--gutter);
  background: color-mix(in srgb, var(--charcoal) 88%, transparent);
  backdrop-filter: blur(14px);
  border-block-end: 1px solid var(--line);
}

.tlm-crumb {
  display: flex;
  align-items: center;
  gap: var(--s-2);
  font-size: var(--fs-xs);
  letter-spacing: 0.08em;
  min-inline-size: 0;
}

.tlm-crumb__brand { font-weight: 700; color: var(--text); letter-spacing: 0.18em; }
.tlm-crumb__sep   { color: var(--text-dim); }
.tlm-crumb__mid   { color: var(--text-dim); }
.tlm-crumb__here  {
  color: var(--accent);
  font-weight: 600;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

@media (max-width: 560px) {
  .tlm-crumb__mid,
  .tlm-crumb__sep--mid { display: none; }
}

.tlm-header__actions {
  margin-inline-start: auto;
  display: flex;
  align-items: center;
  gap: var(--s-2);
}

.sidenav {
  display: none;
}

@media (min-width: 1024px) {
  .sidenav {
    display: flex;
    flex-direction: column;
    position: sticky;
    inset-block-start: 0;
    block-size: 100dvh;
    padding: var(--s-6) var(--s-5);
    border-inline-start: 1px solid var(--line);  
    background: var(--graphite);
    overflow-y: auto;
    overscroll-behavior: contain;
  }
}

.sidenav__mark {
  font-size: var(--fs-xs);
  letter-spacing: 0.2em;
  font-weight: 700;
  color: var(--text-dim);
  margin-block-end: var(--s-2);
}

.sidenav__project {
  font-size: var(--fs-sm);
  font-weight: 600;
  color: var(--text);
  margin-block-end: var(--s-6);
  line-height: 1.4;
}

.sidenav__list { display: flex; flex-direction: column; gap: var(--s-1); }

.chapter-link {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  align-items: center;
  gap: var(--s-3);
  inline-size: 100%;
  text-align: start;
  padding: var(--s-3);
  border-radius: var(--radius);
  color: var(--text-dim);
  font-size: var(--fs-sm);
  min-block-size: 44px;
  transition: background var(--dur-fast) var(--ease),
              color var(--dur-fast) var(--ease);
}

.chapter-link:hover { background: rgba(255,255,255,.04); color: var(--text-muted); }

.chapter-link[aria-current='true'] {
  color: var(--text);
  font-weight: 600;
  background: rgba(255,255,255,.05);
}
.chapter-link[aria-current='true'] .chapter-link__num {
  color: var(--accent);
}
.chapter-link[aria-current='true']::before {
  content: '';
  position: absolute;
  inset-inline-end: 0;
  inline-size: 3px;
  block-size: 60%;
  background: var(--accent);
  border-radius: 2px;
}
.chapter-link { position: relative; }

.chapter-link__num {
  font-size: var(--fs-xs);
  font-variant-numeric: tabular-nums;
  color: var(--text-dim);
  direction: ltr;
}

.chapter-link__label {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.sidenav__foot {
  margin-block-start: auto;
  padding-block-start: var(--s-5);
  border-block-start: 1px solid var(--line);
  display: flex;
  flex-direction: column;
  gap: var(--s-3);
}

.drawer {
  position: fixed;
  inset: 0;
  z-index: 90;
  visibility: hidden;
  pointer-events: none;
}
.drawer[data-open='true'] { visibility: visible; pointer-events: auto; }

.drawer__scrim {
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,.6);
  opacity: 0;
  transition: opacity var(--dur) var(--ease);
}
.drawer[data-open='true'] .drawer__scrim { opacity: 1; }

.drawer__panel {
  position: absolute;
  inset-block: 0;
  inset-inline-end: 0;
  inline-size: min(84vw, 340px);
  background: var(--graphite);
  border-inline-start: 1px solid var(--line);
  padding: var(--s-5);
  display: flex;
  flex-direction: column;
  gap: var(--s-4);
  overflow-y: auto;
  overscroll-behavior: contain;
  
  transform: translateX(100%);
  transition: transform var(--dur) var(--ease-out);
  padding-block-end: calc(var(--s-6) + env(safe-area-inset-bottom));
}

[dir='rtl'] .drawer__panel { transform: translateX(-100%); }

.drawer[data-open='true'] .drawer__panel,
[dir='rtl'] .drawer[data-open='true'] .drawer__panel { transform: translateX(0); }

.drawer__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--s-3);
  padding-block-end: var(--s-4);
  border-block-end: 1px solid var(--line);
}

@media (min-width: 1024px) {
  .drawer, .drawer-toggle { display: none; }
}

.progress {
  position: fixed;
  inset-block-start: 0;
  inset-inline: 0;
  block-size: 2px;
  z-index: 100;
  background: transparent;
  pointer-events: none;
}
.progress__fill {
  block-size: 100%;
  inline-size: 0%;
  background: var(--accent);
  transform-origin: inline-start;
  transition: inline-size 120ms linear;
}

.chapter {
  padding-block: clamp(var(--s-8), 9vw, var(--s-10));
  border-block-start: 1px solid var(--line);
  scroll-margin-block-start: calc(var(--header-h) + var(--s-4));
}
.chapter:first-of-type { border-block-start: 0; }

.chapter__head {
  max-inline-size: var(--content-max);
  margin-inline: auto;
  padding-inline: var(--gutter);
  margin-block-end: var(--s-7);
}

.chapter__num {
  font-size: var(--fs-xs);
  letter-spacing: 0.24em;
  color: var(--accent);
  font-weight: 700;
  direction: ltr;
  display: inline-block;
}

.chapter__title { margin-block-start: var(--s-2); }

.scene {
  max-inline-size: var(--content-max);
  margin-inline: auto;
  padding: var(--s-6) var(--gutter);
  scroll-margin-block-start: calc(var(--header-h) + var(--s-4));
}

.scene--wide { max-inline-size: var(--content-wide); }

.scene__head {
  display: flex;
  align-items: baseline;
  gap: var(--s-3);
  flex-wrap: wrap;
  margin-block-end: var(--s-4);
}

.scene__index {
  font-size: var(--fs-xs);
  color: var(--text-dim);
  font-variant-numeric: tabular-nums;
  direction: ltr;
}

.scene__body { display: grid; gap: var(--s-5); }

.scene--split .scene__body {
  grid-template-columns: 1fr;
}
@media (min-width: 900px) {
  .scene--split .scene__body {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: var(--s-6);
    align-items: start;
  }
}

@media (min-width: 1024px) and (max-height: 800px) {
  :root { --s-9: 4.5rem; --s-10: 5.5rem; }
  .chapter { padding-block: var(--s-8); }
  h1 { font-size: clamp(2.25rem, 3vw, 3rem); }
}

@media (min-width: 1800px) {
  :root { --content-max: 1360px; --content-wide: 1640px; }
}

@media (max-width: 767px) {
  :root { --gutter: 1.25rem; }

  .scene { padding-block: var(--s-5); }

  
  .scene__body,
  .cmp__panes,
  .pkg-grid,
  .value-grid { grid-template-columns: 1fr !important; }
}

@media (max-width: 380px) {
  :root { --gutter: 1rem; }
}