.page-faq {
  background: var(--c-pitch);
  color: var(--c-lamp);
  padding-bottom: 64px;
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */
.page-faq .faq-hero {
  padding-top: calc(var(--header-h) + 44px);
  padding-bottom: 48px;
  background:
    radial-gradient(120% 88% at 84% 4%, rgba(53, 242, 208, .17), transparent 62%),
    radial-gradient(90% 70% at 4% 96%, rgba(255, 122, 51, .10), transparent 60%),
    linear-gradient(180deg, #0d352b 0%, var(--c-pitch) 74%);
}

.page-faq .faq-hero-grid {
  display: grid;
  gap: 36px;
  align-items: end;
}

.page-faq .faq-hero-copy {
  min-width: 0;
}

.page-faq .faq-title {
  margin: 18px 0 0;
  font-size: clamp(42px, 10.5vw, 92px);
  font-weight: 200;
  line-height: .95;
  letter-spacing: -.03em;
  color: var(--c-lamp);
}

.page-faq .faq-title em {
  font-style: normal;
  color: var(--c-neon);
}

.page-faq .faq-hero-copy .t-lede {
  margin: 22px 0 0;
  max-width: 46ch;
}

.page-faq .faq-hero-actions {
  margin-top: 28px;
}

.page-faq .faq-hero-media {
  aspect-ratio: 9 / 7;
  border-radius: var(--radius-card);
  background: linear-gradient(160deg, #123a30, var(--c-room));
}

/* ---------- 问答板 ---------- */
.page-faq .faq-board {
  padding-top: 8px;
}

.page-faq .faq-board-grid {
  display: grid;
  gap: 32px;
  align-items: start;
}

.page-faq .faq-index {
  border: 1px solid var(--c-grid);
  border-radius: var(--radius-card);
  background: var(--c-room);
  padding: 18px 16px;
}

.page-faq .faq-index .t-h3 {
  margin: 0 0 12px;
  font-size: 15px;
  letter-spacing: .04em;
  color: var(--c-mist);
  font-weight: 600;
}

.page-faq .faq-index-list {
  display: flex;
  gap: 6px;
  margin: 0;
  padding: 0 0 4px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-faq .faq-index-list::-webkit-scrollbar {
  height: 4px;
}

.page-faq .faq-index-list::-webkit-scrollbar-thumb {
  background: var(--c-grid);
  border-radius: 999px;
}

.page-faq .faq-index-item {
  display: block;
  padding: 10px 14px 10px 12px;
  border-left: 2px solid transparent;
  border-radius: 0 14px 14px 0;
  color: var(--c-mist);
  font-size: 15px;
  line-height: 1.4;
  text-decoration: none;
  white-space: nowrap;
  transition: color .18s var(--ease), border-color .18s var(--ease), background-color .18s var(--ease);
}

.page-faq .faq-index-num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  margin-right: 8px;
  color: var(--c-mist);
  opacity: .8;
}

.page-faq .faq-index-item:hover,
.page-faq .faq-index-item:focus-visible {
  color: var(--c-lamp);
  border-left-color: var(--c-neon);
  background: rgba(53, 242, 208, .07);
}

.page-faq .faq-index-item.is-active {
  color: var(--c-neon);
  border-left-color: var(--c-neon);
  background: rgba(53, 242, 208, .10);
}

.page-faq .faq-groups {
  min-width: 0;
}

.page-faq .faq-group {
  scroll-margin-top: calc(var(--header-h) + 28px);
}

.page-faq .faq-group .sec-head {
  margin: 0;
}

.page-faq .faq-list {
  display: grid;
  gap: 12px;
  margin-top: 20px;
  counter-reset: faqq;
}

.page-faq .faq-item {
  counter-increment: faqq;
  border: 1px solid var(--c-grid);
  border-radius: var(--radius-card);
  background: rgba(18, 58, 48, .55);
  overflow: hidden;
  transition: border-color .2s var(--ease), background-color .2s var(--ease), transform .2s var(--ease);
}

.page-faq .faq-item:hover {
  border-color: rgba(53, 242, 208, .45);
  transform: translateY(-2px);
}

.page-faq .faq-item[open] {
  border-color: var(--c-neon);
  background: rgba(18, 58, 48, .8);
}

.page-faq .faq-item summary {
  display: flex;
  align-items: baseline;
  gap: 16px;
  padding: 20px 22px;
  cursor: pointer;
  list-style: none;
  font-size: 20px;
  line-height: 1.5;
  color: var(--c-lamp);
  transition: color .18s var(--ease);
}

.page-faq .faq-item summary::-webkit-details-marker {
  display: none;
}

.page-faq .faq-item summary::before {
  content: counter(faqq, decimal-leading-zero);
  flex: none;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .06em;
  color: var(--c-mist);
  transition: color .24s var(--ease);
}

.page-faq .faq-item[open] summary::before {
  color: var(--c-whistle);
}

.page-faq .faq-item summary::after {
  content: "";
  flex: none;
  margin-left: auto;
  align-self: center;
  width: 11px;
  height: 11px;
  border-right: 2px solid var(--c-mist);
  border-bottom: 2px solid var(--c-mist);
  transform: rotate(45deg);
  transition: transform .24s var(--ease), border-color .24s var(--ease);
}

.page-faq .faq-item[open] summary::after {
  transform: rotate(-135deg);
  border-color: var(--c-neon);
}

.page-faq .faq-item summary:hover {
  color: var(--c-neon);
}

.page-faq .faq-a {
  padding: 0 22px 22px 54px;
  max-width: 68ch;
  font-size: 16px;
  line-height: 1.8;
  color: var(--c-mist);
}

.page-faq .faq-a p {
  margin: 0 0 .85em;
}

.page-faq .faq-a p:last-child {
  margin-bottom: 0;
}

/* ---------- 时间条 ---------- */
.page-faq .faq-timeline {
  margin: 22px 0 0;
  padding: 20px 18px 16px;
  border: 1px dashed var(--c-grid);
  border-radius: var(--radius-card);
  background: rgba(6, 26, 21, .62);
  overflow-x: auto;
}

.page-faq .faq-timeline svg {
  display: block;
  width: 100%;
  min-width: 520px;
  height: auto;
}

.page-faq .faq-timeline figcaption {
  margin-top: 12px;
  min-width: 520px;
}

.page-faq .tl-line {
  stroke: var(--c-grid);
  stroke-width: 2;
}

.page-faq .tl-node {
  fill: var(--c-pitch);
  stroke: var(--c-neon);
  stroke-width: 2;
}

.page-faq .tl-node--whistle {
  stroke: var(--c-whistle);
}

.page-faq .tl-name {
  fill: var(--c-lamp);
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 600;
}

.page-faq .tl-label {
  fill: var(--c-mist);
  font-family: var(--font-mono);
  font-size: 12px;
}

/* ---------- 勘误区 ---------- */
.page-faq .faq-errata-media {
  margin: 24px 0 0;
  border-radius: var(--radius-card);
  background: linear-gradient(160deg, #123a30, var(--c-room));
}

.page-faq .faq-errata-media figcaption {
  margin-top: 12px;
}

.page-faq .faq-errata-actions {
  margin-top: 20px;
}

/* ---------- 延伸阅读 ---------- */
.page-faq .faq-next {
  margin-top: 96px;
  padding-top: 48px;
  background: linear-gradient(180deg, rgba(6, 26, 21, 0), rgba(6, 26, 21, .85) 40%);
}

.page-faq .faq-next-grid {
  display: grid;
  gap: 32px;
  align-items: start;
}

.page-faq .faq-next-lead .t-h2 {
  margin: 12px 0 0;
}

.page-faq .faq-next-lead .t-lede {
  margin: 16px 0 0;
}

.page-faq .faq-next-list {
  display: grid;
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-faq .faq-next-card {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 22px 24px;
  border: 1px solid var(--c-grid);
  border-radius: var(--radius-card);
  background: var(--c-pill);
  text-decoration: none;
  transition: border-color .2s var(--ease), transform .2s var(--ease);
}

.page-faq .faq-next-card:hover,
.page-faq .faq-next-card:focus-visible {
  border-color: var(--c-neon);
  transform: translateY(-2px);
}

.page-faq .faq-next-name {
  font-size: 20px;
  font-weight: 600;
  color: var(--c-lamp);
}

.page-faq .faq-next-card:hover .faq-next-name {
  color: var(--c-neon);
}

.page-faq .faq-next-desc {
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-mist);
}

/* ---------- 响应式 ---------- */
@media (max-width: 599px) {
  .page-faq .faq-item summary {
    font-size: 17px;
    padding: 17px 18px;
    gap: 12px;
  }

  .page-faq .faq-a {
    padding: 0 18px 18px 18px;
    font-size: 15px;
  }

  .page-faq .faq-timeline {
    padding: 16px 14px 12px;
  }
}

@media (min-width: 760px) {
  .page-faq .faq-next-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: 48px;
  }

  .page-faq .faq-next-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-faq .faq-hero {
    padding-top: calc(var(--header-h) + 64px);
    padding-bottom: 64px;
  }

  .page-faq .faq-hero-grid {
    grid-template-columns: minmax(0, 1.16fr) minmax(0, .84fr);
    gap: 56px;
  }

  .page-faq .faq-board-grid {
    grid-template-columns: 272px minmax(0, 1fr);
    gap: 64px;
  }

  .page-faq .faq-index {
    position: sticky;
    top: calc(var(--header-h) + 28px);
    padding: 22px 18px;
  }

  .page-faq .faq-index-list {
    flex-direction: column;
    gap: 2px;
    overflow: visible;
  }

  .page-faq .faq-index-item {
    white-space: normal;
  }

  .page-faq .faq-groups {
    gap: 72px;
  }

  .page-faq .faq-list {
    margin-top: 24px;
  }
}

@media (min-width: 1200px) {
  .page-faq .faq-a {
    padding-left: 60px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-faq .faq-item,
  .page-faq .faq-next-card {
    transition: border-color .2s var(--ease), background-color .2s var(--ease);
  }

  .page-faq .faq-item:hover,
  .page-faq .faq-next-card:hover,
  .page-faq .faq-next-card:focus-visible {
    transform: none;
  }
}