/* FAQ page: reuses the About shell (.about-page) and adds a readable,
   interactive Q&A layout. Answers are native <details>; faq.js only adds
   search, topic tracking, expand-all, and shareable links. Colors come from
   the shared variables, so light theme follows automatically. */
.faq-page {
  --faq-sans: -apple-system, BlinkMacSystemFont, "Inter", "Segoe UI", Roboto, sans-serif;
  --faq-body: color-mix(in srgb, var(--text) 80%, var(--bg));
  --faq-card: color-mix(in srgb, var(--text) 2.5%, transparent);
  --faq-card-hover: color-mix(in srgb, var(--text) 4.5%, transparent);
  --faq-edge: color-mix(in srgb, var(--text) 10%, transparent);
  --faq-edge-hover: color-mix(in srgb, var(--text) 22%, transparent);
  --faq-ease: cubic-bezier(.2, .7, .2, 1);
  interpolate-size: allow-keywords;
}
@media (prefers-reduced-motion: no-preference) {
  html:has(.faq-page) { scroll-behavior: smooth; }
}

/* ---------- layout: sticky topics + questions ---------- */
.faq-layout {
  display: grid;
  grid-template-columns: 240px minmax(0, 1fr);
  gap: 72px;
  align-items: start;
  padding: 64px 0 24px;
}
.faq-toc { position: sticky; top: 104px; display: grid; gap: 28px; }
.faq-body { min-width: 0; }
.faq-section { padding: 0 0 72px; scroll-margin-top: 96px; }
.faq-section[hidden] { display: none; }

/* ---------- search ---------- */
.faq-search-label {
  display: block;
  margin-bottom: 10px;
  color: var(--muted);
  font: 700 10px var(--mono);
  letter-spacing: 1.6px;
  text-transform: uppercase;
}
.faq-search-input {
  width: 100%;
  padding: 12px 14px;
  border: 1px solid var(--faq-edge);
  border-radius: 10px;
  background: var(--faq-card);
  color: var(--text);
  font: 15px var(--faq-sans);
  transition: border-color .2s ease, background .2s ease;
}
.faq-search-input::placeholder { color: color-mix(in srgb, var(--muted) 70%, transparent); }
.faq-search-input:focus { outline: none; border-color: var(--ember); background: var(--faq-card-hover); }
.faq-search-status { margin-top: 8px; color: var(--muted); font: 11px var(--mono); letter-spacing: .4px; }

/* ---------- topics (scroll-tracked) ---------- */
.faq-topics { display: grid; gap: 2px; border-left: 1px solid var(--line); }
.faq-topic {
  position: relative;
  display: grid;
  grid-template-columns: 28px 1fr auto;
  align-items: center;
  padding: 10px 0 10px 16px;
  color: var(--muted);
  font: 15px var(--faq-sans);
  text-decoration: none;
  transition: color .2s ease;
}
.faq-topic::before {
  content: "";
  position: absolute;
  left: -1px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  border-radius: 2px;
  background: var(--ember);
  transform: scaleY(0);
  transition: transform .3s var(--faq-ease);
}
.faq-topic:hover { color: var(--text); }
.faq-topic[aria-current="true"] { color: var(--text); }
.faq-topic[aria-current="true"]::before { transform: scaleY(1); }
.faq-topic-num { color: var(--ember); font: 11px var(--mono); }
.faq-topic-count { color: var(--muted); font: 11px var(--mono); }
.faq-topic.is-empty { opacity: .35; }

/* ---------- section heads ---------- */
.faq-section-head { display: grid; gap: 0; margin-bottom: 28px; }
.faq-section-head .section-index { margin-bottom: 18px; }
.faq-page .faq-section-head h2 { font-size: clamp(30px, 3.2vw, 46px); line-height: 1.08; }
.faq-section-head p {
  max-width: 62ch;
  margin-top: 18px;
  color: var(--faq-body);
  font: 16px/1.65 var(--faq-sans);
}
.faq-toggle-all {
  justify-self: start;
  margin-top: 20px;
  padding: 7px 14px;
  border: 1px solid var(--faq-edge);
  border-radius: 999px;
  background: none;
  color: var(--muted);
  font: 700 10px var(--mono);
  letter-spacing: 1.4px;
  text-transform: uppercase;
  cursor: pointer;
  transition: color .2s ease, border-color .2s ease;
}
.faq-toggle-all:hover { color: var(--text); border-color: var(--faq-edge-hover); }
.faq-toggle-all:focus-visible { outline: 2px solid var(--ember); outline-offset: 3px; }

/* ---------- question cards ---------- */
.faq-list { display: grid; gap: 10px; }
.faq-item {
  border: 1px solid var(--faq-edge);
  border-radius: 14px;
  background: var(--faq-card);
  transition: border-color .25s ease, background .25s ease, box-shadow .3s ease, transform .3s var(--faq-ease);
}
.faq-item[hidden] { display: none; }
.faq-item { scroll-margin-top: 110px; }
.faq-item:hover { border-color: var(--faq-edge-hover); background: var(--faq-card-hover); }
.faq-item[open] { border-color: var(--faq-edge-hover); background: var(--faq-card-hover); box-shadow: inset 3px 0 0 var(--ember); }
.faq-item.is-target { box-shadow: inset 3px 0 0 var(--ember), 0 0 0 1px var(--ember); }
.faq-item summary {
  display: grid;
  grid-template-columns: 38px minmax(0, 1fr) 20px;
  gap: 12px;
  align-items: baseline;
  padding: 20px 22px;
  list-style: none;
  cursor: pointer;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary:focus-visible { outline: 2px solid var(--ember); outline-offset: -2px; border-radius: 14px; }
.faq-num { color: var(--ember); font: 12px var(--mono); letter-spacing: .5px; }
.faq-q { color: var(--text); font: 600 17.5px/1.45 var(--faq-sans); letter-spacing: -.1px; }
.faq-q mark { padding: 0 2px; border-radius: 3px; background: color-mix(in srgb, var(--ember) 28%, transparent); color: inherit; }
/* Plus that turns into a minus. */
.faq-icon { position: relative; align-self: center; width: 14px; height: 14px; }
.faq-icon::before,
.faq-icon::after {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  width: 14px;
  height: 2px;
  border-radius: 2px;
  background: var(--ember);
  transition: transform .35s var(--faq-ease);
}
.faq-icon::after { transform: rotate(90deg); }
.faq-item[open] .faq-icon::after { transform: rotate(0deg); }

/* Smooth open/close where ::details-content + interpolate-size are
   supported; elsewhere the answer simply appears. */
.faq-item::details-content {
  block-size: 0;
  overflow: clip;
  transition: block-size .42s var(--faq-ease), content-visibility .42s allow-discrete;
}
.faq-item[open]::details-content { block-size: auto; }
.faq-answer {
  max-width: 68ch;
  padding: 0 22px 24px 72px;
  opacity: 0;
  translate: 0 -6px;
  transition: opacity .35s ease .06s, translate .4s var(--faq-ease) .06s;
}
.faq-item[open] .faq-answer { opacity: 1; translate: 0 0; }
.faq-answer p,
.faq-answer li { color: var(--faq-body); font: 15.5px/1.7 var(--faq-sans); }
.faq-answer p + p,
.faq-answer p + ul,
.faq-answer ul + p { margin-top: 14px; }
.faq-answer ul { margin: 0; padding-left: 20px; }
.faq-answer li + li { margin-top: 8px; }
.faq-answer strong { color: var(--text); font-weight: 600; }
.faq-answer a { color: var(--text); text-decoration: none; border-bottom: 1px solid var(--ember); transition: color .2s ease; }
.faq-answer a:hover { color: var(--ember); }
.faq-copy {
  margin-top: 18px;
  padding: 0;
  border: 0;
  background: none;
  color: var(--muted);
  font: 700 10px var(--mono);
  letter-spacing: 1.4px;
  text-transform: uppercase;
  cursor: pointer;
  transition: color .2s ease;
}
.faq-copy:hover,
.faq-copy.is-copied { color: var(--ember); }
.faq-copy:focus-visible { outline: 2px solid var(--ember); outline-offset: 3px; border-radius: 3px; }

/* Volume and supervision figures inside the Option 1 and Option 2 answers. */
.faq-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 20px 0 0;
  border: 1px solid var(--line);
  border-radius: 10px;
  overflow: hidden;
  background: var(--line);
}
.faq-stats > div { padding: 16px 18px; background: var(--bg, #000); }
.faq-stats dt { color: var(--ember); font: 700 10px var(--mono); letter-spacing: 1.6px; text-transform: uppercase; }
.faq-stats dd { margin: 8px 0 0; color: var(--text); font: 15px/1.6 var(--faq-sans); }
.faq-answer .faq-footnote { margin-top: 12px; color: var(--muted); font: 12.5px/1.6 var(--faq-sans); }
.faq-empty { padding: 32px 0 72px; color: var(--faq-body); font: 16px/1.6 var(--faq-sans); }
.faq-empty a { color: var(--text); border-bottom: 1px solid var(--ember); text-decoration: none; }

@media (prefers-reduced-motion: reduce) {
  .faq-item, .faq-topic, .faq-topic::before, .faq-icon::before, .faq-icon::after, .faq-answer { transition: none; }
  .faq-item::details-content { transition: none; }
}

/* ---------- tablet / mobile: topics become a chip row ---------- */
@media (max-width: 980px) {
  .faq-layout { grid-template-columns: minmax(0, 1fr); gap: 36px; padding-top: 48px; }
  .faq-toc { position: static; gap: 18px; }
  .faq-topics {
    display: flex;
    gap: 8px;
    border-left: 0;
    overflow-x: auto;
    padding-bottom: 4px;
    scrollbar-width: none;
  }
  .faq-topics::-webkit-scrollbar { display: none; }
  .faq-topic {
    display: inline-flex;
    flex: none;
    gap: 8px;
    padding: 8px 14px;
    border: 1px solid var(--faq-edge);
    border-radius: 999px;
    font-size: 14px;
  }
  .faq-topic::before { display: none; }
  .faq-topic[aria-current="true"] { border-color: var(--ember); }
}
@media (max-width: 700px) {
  .faq-section { padding-bottom: 56px; }
  .faq-item summary { grid-template-columns: 30px minmax(0, 1fr) 16px; gap: 10px; padding: 18px 16px; }
  .faq-q { font-size: 16.5px; }
  .faq-answer { padding: 0 16px 20px 16px; }
  .faq-stats { grid-template-columns: minmax(0, 1fr); }
}