.page-faq {
  --faq-line: rgba(127, 231, 255, .22);
  --faq-line-soft: rgba(127, 231, 255, .12);
  --faq-panel: rgba(14, 58, 92, .42);
  --faq-panel-strong: rgba(14, 58, 92, .66);
  --faq-text: rgba(217, 226, 236, .82);
  --faq-gap: clamp(18px, 2.6vw, 32px);
  color: var(--by-pearl);
  font-family: var(--by-font-body);
}

.page-faq *,
.page-faq *::before,
.page-faq *::after {
  box-sizing: border-box;
}

.page-faq .faq-shell {
  width: 100%;
  max-width: var(--by-shell);
  margin-inline: auto;
  padding-inline: var(--by-gutter);
}

/* ---------- 面包屑 ---------- */
.page-faq .faq-crumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  max-width: var(--by-shell);
  margin-inline: auto;
  padding: 16px var(--by-gutter) 0;
  font-size: 14px;
  color: rgba(217, 226, 236, .66);
}

.page-faq .faq-crumb a {
  color: var(--by-electric-soft);
  text-decoration: none;
}

.page-faq .faq-crumb a:hover,
.page-faq .faq-crumb a:focus-visible {
  color: var(--by-electric);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- 首屏 ---------- */
.page-faq .faq-hero {
  position: relative;
  margin-top: 16px;
  padding: clamp(30px, 5vw, 62px) 0 clamp(24px, 4vw, 44px);
  background-image:
    radial-gradient(120% 92% at 6% 0%, rgba(0, 212, 255, .20) 0%, rgba(0, 212, 255, 0) 58%),
    linear-gradient(158deg, #0E3A5C 0%, #0A2540 62%, #07131F 100%);
  border-top: 2px solid var(--faq-line);
  border-bottom: 2px solid var(--faq-line);
  overflow: hidden;
}

.page-faq .faq-hero__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(24px, 3.6vw, 46px);
  align-items: center;
}

.page-faq .faq-hero__title {
  margin: 12px 0 0;
  font-family: var(--by-font-head);
  font-size: clamp(30px, 5.6vw, 58px);
  font-weight: 800;
  line-height: 1.12;
  letter-spacing: .02em;
  color: var(--by-sand);
}

.page-faq .faq-hero__lede {
  margin: 18px 0 0;
  max-width: 46ch;
  font-size: clamp(15.5px, 1.5vw, 18px);
  line-height: 1.78;
  color: var(--faq-text);
}

.page-faq .faq-stats {
  display: flex;
  flex-wrap: wrap;
  gap: clamp(16px, 2.4vw, 34px);
  margin: 26px 0 0;
}

.page-faq .faq-stat {
  display: flex;
  flex-direction: column-reverse;
  gap: 6px;
  min-width: 108px;
  padding-left: 14px;
  border-left: 3px solid var(--by-line-strong);
}

.page-faq .faq-stat__value {
  margin: 0;
  font-family: var(--by-font-mono);
  font-size: clamp(26px, 3vw, 36px);
  font-weight: 700;
  line-height: 1;
  color: var(--by-electric);
}

.page-faq .faq-stat__value small {
  margin-left: 4px;
  font-size: .48em;
  color: var(--by-electric-soft);
}

.page-faq .faq-stat__label {
  font-size: 13px;
  letter-spacing: .05em;
  color: rgba(217, 226, 236, .7);
}

.page-faq .faq-hero__figure {
  margin: 0;
  border: 2px solid var(--by-line-strong);
  border-radius: var(--by-radius-l);
  background: var(--by-ink);
  box-shadow: var(--by-shadow-card);
  overflow: hidden;
}

.page-faq .faq-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 12 / 7;
  object-fit: cover;
}

.page-faq .faq-hero__index {
  margin-top: clamp(26px, 3.8vw, 42px);
}

.page-faq .faq-index__label {
  margin: 0;
  font-family: var(--by-font-mono);
  font-size: 12.5px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: rgba(127, 231, 255, .74);
}

.page-faq .faq-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 12px 0 0;
  padding: 0;
  list-style: none;
}

.page-faq .faq-chip {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 9px 16px;
  border: 2px solid var(--faq-line);
  border-radius: 999px;
  background: rgba(7, 19, 31, .44);
  font-size: 15px;
  color: var(--by-electric-soft);
  text-decoration: none;
  transition: transform .18s ease, border-color .18s ease, background-color .18s ease, color .18s ease;
}

.page-faq .faq-chip::before {
  content: "";
  flex: none;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--by-coral);
}

.page-faq .faq-chip:hover,
.page-faq .faq-chip:focus-visible {
  transform: translateY(-2px);
  border-color: var(--by-line-strong);
  background: rgba(0, 212, 255, .14);
  color: var(--by-sand);
}

/* ---------- 主体网格 ---------- */
.page-faq .faq-body {
  padding: clamp(34px, 5vw, 68px) 0 clamp(44px, 6vw, 84px);
}

.page-faq .faq-body__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(26px, 3.4vw, 48px);
}

/* ---------- 左侧索引 ---------- */
.page-faq .faq-toc {
  border: 2px solid var(--faq-line);
  border-radius: var(--by-radius-m);
  background: var(--faq-panel);
  padding: 20px 20px 22px;
  box-shadow: 6px 6px 0 rgba(7, 19, 31, .45);
}

.page-faq .faq-toc__title {
  margin: 0 0 14px;
  font-family: var(--by-font-head);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--by-electric);
}

.page-faq .faq-toc__list {
  display: grid;
  gap: 2px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-faq .faq-toc__list a {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 9px 10px;
  border-left: 2px solid transparent;
  border-radius: var(--by-radius-s);
  font-size: 15px;
  color: rgba(217, 226, 236, .84);
  text-decoration: none;
  transition: background-color .18s ease, color .18s ease, border-color .18s ease;
}

.page-faq .faq-toc__list a:hover,
.page-faq .faq-toc__list a:focus-visible {
  background: rgba(0, 212, 255, .1);
  border-left-color: var(--by-electric);
  color: var(--by-sand);
}

.page-faq .faq-toc__no {
  font-family: var(--by-font-mono);
  font-size: 12.5px;
  color: var(--by-coral);
}

.page-faq .faq-toc__note {
  margin: 16px 0 0;
  padding-top: 14px;
  border-top: 1px solid var(--faq-line-soft);
  font-size: 13.5px;
  line-height: 1.7;
  color: rgba(217, 226, 236, .68);
}

.page-faq .faq-toc__link {
  display: inline-block;
  margin-top: 12px;
  font-size: 14px;
  color: var(--by-electric);
  text-decoration: none;
}

.page-faq .faq-toc__link::after {
  content: " →";
}

.page-faq .faq-toc__link:hover,
.page-faq .faq-toc__link:focus-visible {
  color: var(--by-electric-soft);
  text-decoration: underline;
  text-underline-offset: 3px;
}

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

.page-faq .faq-group {
  margin-top: clamp(32px, 4.4vw, 54px);
  padding-top: clamp(22px, 3vw, 34px);
  border-top: 2px solid var(--faq-line);
  scroll-margin-top: calc(var(--by-header-h) + 24px);
}

.page-faq .faq-group:first-child {
  margin-top: 0;
  padding-top: 0;
  border-top: 0;
}

.page-faq .faq-group__head {
  display: flex;
  align-items: flex-start;
  gap: 14px;
}

.page-faq .faq-group__no {
  flex: none;
  padding: 4px 9px;
  border: 2px solid rgba(255, 107, 74, .55);
  border-radius: var(--by-radius-s);
  font-family: var(--by-font-mono);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: .08em;
  color: var(--by-coral);
}

.page-faq .faq-group__title {
  margin: 0;
  font-family: var(--by-font-head);
  font-size: clamp(21px, 2.8vw, 30px);
  font-weight: 700;
  letter-spacing: .01em;
  color: var(--by-sand);
}

.page-faq .faq-group__lede {
  margin: 8px 0 0;
  max-width: 54ch;
  font-size: 15.5px;
  line-height: 1.72;
  color: var(--faq-text);
}

/* ---------- 信息图 ---------- */
.page-faq .faq-figure {
  margin: 22px 0 0;
  border: 2px solid var(--faq-line);
  border-radius: var(--by-radius-m);
  background: var(--by-ink);
  box-shadow: 7px 7px 0 rgba(7, 19, 31, .5);
  overflow: hidden;
}

.page-faq .faq-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 10 / 7;
  object-fit: cover;
}

.page-faq .faq-figure__caption {
  padding: 12px 16px 14px;
  border-top: 1px solid var(--faq-line-soft);
  font-size: 13.5px;
  line-height: 1.66;
  color: rgba(217, 226, 236, .7);
}

/* ---------- 问答条目 ---------- */
.page-faq .faq-list {
  display: grid;
  gap: 14px;
  margin-top: 22px;
}

.page-faq .faq-item {
  border: 2px solid var(--faq-line);
  border-radius: var(--by-radius-m);
  background: var(--faq-panel);
  box-shadow: 5px 5px 0 rgba(7, 19, 31, .42);
  transition: border-color .2s ease, box-shadow .2s ease, background-color .2s ease;
}

.page-faq .faq-item[open] {
  border-color: var(--by-line-strong);
  background: var(--faq-panel-strong);
  box-shadow: 9px 9px 0 rgba(7, 19, 31, .55);
}

.page-faq .faq-item__q {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 16px 18px;
  cursor: pointer;
  list-style: none;
  font-family: var(--by-font-head);
  font-size: clamp(15.5px, 1.6vw, 17.5px);
  font-weight: 600;
  line-height: 1.5;
  color: var(--by-sand);
  transition: color .18s ease;
}

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

.page-faq .faq-item__q:hover {
  color: var(--by-electric-soft);
}

.page-faq .faq-item__q:focus-visible {
  outline: 2px solid var(--by-electric);
  outline-offset: -4px;
  border-radius: var(--by-radius-m);
}

.page-faq .faq-item__no {
  flex: none;
  padding-top: 3px;
  font-family: var(--by-font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .06em;
  color: var(--by-coral);
}

.page-faq .faq-item__text {
  flex: 1 1 auto;
  min-width: 0;
}

.page-faq .faq-item__mark {
  position: relative;
  flex: none;
  width: 20px;
  height: 20px;
  margin-top: 2px;
}

.page-faq .faq-item__mark::before,
.page-faq .faq-item__mark::after {
  content: "";
  position: absolute;
  border-radius: 2px;
  background: var(--by-electric);
  transition: transform .22s ease, opacity .22s ease;
}

.page-faq .faq-item__mark::before {
  top: 9px;
  left: 0;
  width: 20px;
  height: 2px;
}

.page-faq .faq-item__mark::after {
  top: 0;
  left: 9px;
  width: 2px;
  height: 20px;
}

.page-faq .faq-item[open] .faq-item__mark::after {
  transform: scaleY(0);
  opacity: 0;
}

.page-faq .faq-item__a {
  margin: 0 18px 18px;
  padding-left: 16px;
  border-left: 3px solid var(--by-electric);
}

.page-faq .faq-item__a p {
  margin: 0 0 10px;
  max-width: 64ch;
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--faq-text);
}

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

.page-faq .faq-item__a a {
  color: var(--by-electric);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-faq .faq-item__a a:hover,
.page-faq .faq-item__a a:focus-visible {
  color: var(--by-electric-soft);
}

/* ---------- 底部引导 ---------- */
.page-faq .faq-callout {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  margin-top: clamp(34px, 4.4vw, 56px);
  padding: clamp(20px, 3vw, 30px);
  border: 2px solid rgba(255, 107, 74, .5);
  border-radius: var(--by-radius-m);
  background-image: linear-gradient(120deg, rgba(255, 107, 74, .16) 0%, rgba(10, 37, 64, .28) 72%);
  box-shadow: 8px 8px 0 rgba(7, 19, 31, .48);
}

.page-faq .faq-callout__copy {
  min-width: 0;
  flex: 1 1 320px;
}

.page-faq .faq-callout__title {
  margin: 0;
  font-family: var(--by-font-head);
  font-size: clamp(19px, 2.2vw, 24px);
  font-weight: 700;
  color: var(--by-sand);
}

.page-faq .faq-callout__text {
  margin: 10px 0 0;
  max-width: 58ch;
  font-size: 15px;
  line-height: 1.72;
  color: var(--faq-text);
}

/* ---------- 响应式 ---------- */
@media (min-width: 900px) {
  .page-faq .faq-hero__grid {
    grid-template-columns: minmax(0, 1.18fr) minmax(0, .82fr);
  }
}

@media (min-width: 1000px) {
  .page-faq .faq-body__grid {
    grid-template-columns: 238px minmax(0, 1fr);
    align-items: start;
  }

  .page-faq .faq-toc {
    position: sticky;
    top: calc(var(--by-header-h) + 24px);
  }
}

@media (max-width: 560px) {
  .page-faq .faq-stat {
    min-width: 0;
    flex: 1 1 40%;
  }

  .page-faq .faq-item__q {
    padding: 14px 15px;
  }

  .page-faq .faq-item__a {
    margin: 0 15px 16px;
    padding-left: 13px;
  }

  .page-faq .faq-group__head {
    flex-direction: column;
    gap: 10px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-faq .faq-chip,
  .page-faq .faq-item,
  .page-faq .faq-item__mark::before,
  .page-faq .faq-item__mark::after,
  .page-faq .faq-toc__list a {
    transition: none;
  }
}