.page-faq {
  --faq-indent: 3.2em;
  --faq-rail-gap: 14px;
  box-sizing: border-box;
  width: 100%;
  max-width: calc(var(--shell) + var(--edge) * 2);
  margin-inline: auto;
  padding-inline: var(--edge);
  padding-bottom: calc(var(--band) * 1.3);
  color: var(--c-white);
}

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

/* ---------- 首屏 ---------- */

.page-faq .faq-hero {
  padding-top: clamp(28px, 4vw, 52px);
  padding-bottom: var(--band);
  border-bottom: 1px solid var(--c-orbit);
}

.page-faq .faq-hero .breadcrumb {
  margin-bottom: clamp(28px, 5vw, 56px);
}

.page-faq .faq-hero__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(32px, 5vw, 64px);
  align-items: center;
}

.page-faq .faq-hero__eyebrow {
  margin: 0 0 18px;
  font-size: 12px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--c-grey);
  position: relative;
  padding-left: 20px;
}

.page-faq .faq-hero__eyebrow::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  width: 10px;
  height: 1px;
  background: var(--c-nebula);
}

.page-faq .faq-hero h1 {
  margin: 0 0 clamp(20px, 2.6vw, 30px);
  font-size: clamp(2.1rem, 5.4vw, 4.2rem);
  font-weight: 300;
  line-height: 1.08;
  letter-spacing: 0.05em;
  color: var(--c-white);
}

.page-faq .faq-hero__intro {
  margin: 0 0 18px;
  max-width: 36em;
  font-size: 16.5px;
  line-height: 1.85;
  color: var(--c-grey);
}

.page-faq .faq-hero__hint {
  margin: 0;
  max-width: 34em;
  padding-left: 16px;
  border-left: 1px solid var(--c-orbit);
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--c-grey);
}

/* ---------- 图片框 ---------- */

.page-faq .faq-figure {
  margin: 0;
}

.page-faq .faq-figure .media-frame__img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-faq .faq-figure--wide .media-frame__img {
  aspect-ratio: 2 / 1;
}

.page-faq .faq-hero__figure {
  align-self: stretch;
}

/* ---------- 双栏对照结构 ---------- */

.page-faq .faq-deck {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 4vw, 56px);
  padding-top: var(--band);
}

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

.page-faq .faq-rail__title {
  margin: 0 0 14px;
  font-size: 12px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--c-violet-soft);
}

.page-faq .faq-rail__list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding-bottom: 6px;
  scrollbar-width: thin;
}

.page-faq .faq-rail__link {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 8px 12px;
  border-bottom: 2px solid transparent;
  color: var(--c-grey);
  font-size: 14px;
  line-height: 1.4;
  text-decoration: none;
  white-space: nowrap;
  transition: color var(--t-fast) linear, border-color var(--t-fast) linear;
}

.page-faq .faq-rail__range {
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--c-orbit);
  transition: color var(--t-fast) linear;
}

.page-faq .faq-rail__link:hover {
  color: var(--c-white);
  border-bottom-color: var(--c-orbit);
}

.page-faq .faq-rail__link.is-active,
.page-faq .faq-rail__link[aria-current="true"] {
  color: var(--c-white);
  border-bottom-color: var(--c-violet);
}

.page-faq .faq-rail__link.is-active .faq-rail__range,
.page-faq .faq-rail__link[aria-current="true"] .faq-rail__range {
  color: var(--c-violet-soft);
}

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

/* ---------- 分组 ---------- */

.page-faq .faq-group + .faq-group {
  margin-top: clamp(52px, 7vw, 92px);
}

.page-faq .faq-group__head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  padding-bottom: 14px;
  margin-bottom: 10px;
  border-bottom: 1px solid var(--c-orbit);
  position: relative;
}

.page-faq .faq-group__head::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 44px;
  height: 1px;
  background: var(--c-violet);
}

.page-faq .faq-group__title {
  margin: 0;
  font-size: clamp(1.35rem, 2.6vw, 1.9rem);
  font-weight: 400;
  letter-spacing: 0.05em;
  line-height: 1.2;
  color: var(--c-white);
}

.page-faq .faq-group__meta {
  flex: 0 0 auto;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--c-grey);
}

/* ---------- 问答条目 ---------- */

.page-faq .faq-item {
  border-bottom: 1px solid var(--c-orbit);
}

.page-faq .faq-item__q {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: clamp(16px, 2.2vw, 22px) 0;
  cursor: pointer;
  list-style: none;
  transition: color var(--t-fast) linear;
}

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

.page-faq .faq-item__no {
  flex: 0 0 auto;
  width: var(--faq-indent);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--c-grey);
  transition: color var(--t-fast) linear;
}

.page-faq .faq-item__title {
  flex: 1 1 auto;
  font-size: clamp(15px, 1.5vw, 17px);
  font-weight: 400;
  line-height: 1.6;
  color: var(--c-white);
  transition: color var(--t-fast) linear;
}

.page-faq .faq-item__mark {
  position: relative;
  flex: 0 0 auto;
  align-self: center;
  width: 14px;
  height: 14px;
}

.page-faq .faq-item__mark::before,
.page-faq .faq-item__mark::after {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  width: 14px;
  height: 1px;
  background: var(--c-grey);
  transition: transform var(--t-fast) linear, background var(--t-fast) linear;
}

.page-faq .faq-item__mark::after {
  transform: rotate(90deg);
}

.page-faq .faq-item__q:hover .faq-item__title {
  color: var(--c-violet-soft);
}

.page-faq .faq-item[open] .faq-item__no {
  color: var(--c-violet-soft);
}

.page-faq .faq-item[open] .faq-item__mark::before,
.page-faq .faq-item[open] .faq-item__mark::after {
  background: var(--c-violet-soft);
}

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

.page-faq .faq-item__a {
  max-width: 62ch;
  padding: 0 0 clamp(18px, 2.4vw, 28px);
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--c-grey);
}

.page-faq .faq-item__a a {
  color: var(--c-violet-soft);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--t-draw) linear;
}

.page-faq .faq-item__a a:hover {
  border-bottom-color: currentColor;
}

/* ---------- 步骤 ---------- */

.page-faq .faq-steps {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-faq .faq-steps li {
  position: relative;
  padding-left: 1.4em;
  margin-bottom: 6px;
}

.page-faq .faq-steps li:last-child {
  margin-bottom: 0;
}

.page-faq .faq-steps li::before {
  content: "–";
  position: absolute;
  left: 0;
  color: var(--c-violet-soft);
}

.page-faq .faq-steps .mono {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--c-white);
}

.page-faq .faq-copy {
  display: inline-flex;
  align-items: center;
  margin-top: 14px;
  padding: 6px 13px;
  border: 1px solid var(--c-orbit);
  background: transparent;
  color: var(--c-grey);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  cursor: pointer;
  transition: color var(--t-fast) linear, border-color var(--t-fast) linear;
}

.page-faq .faq-copy:hover {
  color: var(--c-white);
  border-color: var(--c-violet-soft);
}

.page-faq .faq-copy[data-copied] {
  color: var(--c-aurora);
  border-color: var(--c-aurora);
}

/* ---------- 宽屏：左侧索引固定 ---------- */

@media (min-width: 900px) {
  .page-faq .faq-hero__grid {
    grid-template-columns: minmax(0, 1.2fr) minmax(0, 0.8fr);
    align-items: end;
  }
}

@media (min-width: 1024px) {
  .page-faq .faq-deck {
    grid-template-columns: minmax(180px, 3fr) minmax(0, 9fr);
    gap: clamp(32px, 4.6vw, 72px);
  }

  .page-faq .faq-rail {
    position: sticky;
    top: 132px;
    align-self: start;
    border-left: 1px solid var(--c-orbit);
    padding-left: 18px;
  }

  .page-faq .faq-rail__title {
    margin-bottom: 16px;
  }

  .page-faq .faq-rail__list {
    display: block;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-faq .faq-rail__item + .faq-rail__item {
    margin-top: 2px;
  }

  .page-faq .faq-rail__link {
    display: grid;
    grid-template-columns: 4.4em minmax(0, 1fr);
    gap: 8px;
    align-items: baseline;
    padding: 9px 8px 9px 0;
    border-bottom: 0;
    border-left: 2px solid transparent;
    white-space: normal;
    transition: color var(--t-fast) linear, border-color var(--t-fast) linear;
  }

  .page-faq .faq-rail__link:hover {
    border-bottom-color: transparent;
    border-left-color: var(--c-orbit);
  }

  .page-faq .faq-rail__link.is-active,
  .page-faq .faq-rail__link[aria-current="true"] {
    border-left-color: var(--c-violet);
  }

  .page-faq .faq-item__a {
    padding-left: calc(var(--faq-indent) + var(--faq-rail-gap));
  }
}

@media (min-width: 1280px) {
  .page-faq .faq-hero h1 {
    letter-spacing: 0.06em;
  }
}

/* ---------- 窄屏收束 ---------- */

@media (max-width: 640px) {
  .page-faq .faq-item__q {
    gap: 10px;
    align-items: flex-start;
  }

  .page-faq .faq-item__no {
    width: 2.6em;
    padding-top: 3px;
  }

  .page-faq .faq-item__mark {
    align-self: flex-start;
    margin-top: 8px;
  }

  .page-faq .faq-hero__hint {
    font-size: 14px;
  }

  .page-faq .faq-group__head {
    flex-wrap: wrap;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-faq .faq-rail__link,
  .page-faq .faq-item__q,
  .page-faq .faq-item__title,
  .page-faq .faq-item__no,
  .page-faq .faq-item__mark::before,
  .page-faq .faq-item__mark::after,
  .page-faq .faq-copy,
  .page-faq .faq-item__a a {
    transition: none;
  }
}