.page-faq {
  --faq-rail-w: 208px;
  --faq-rail-gap: 36px;
  --faq-sticky-top: 88px;
  color: var(--ink);
}

/* ---------- 首屏 ---------- */
.page-faq .faq-hero {
  position: relative;
  border-bottom: 1px solid var(--line);
  background-color: var(--floor);
  background-image:
    radial-gradient(90% 140% at 90% 0%, rgba(59, 240, 198, 0.10), transparent 60%),
    repeating-linear-gradient(90deg, rgba(30, 74, 60, 0.25) 0 1px, transparent 1px 72px);
}

.page-faq .faq-hero__inner {
  padding-top: 26px;
  padding-bottom: 24px;
}

.page-faq .breadcrumb {
  margin: 0 0 18px;
}

.page-faq .breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: var(--fs-12);
  color: var(--dim);
}

.page-faq .breadcrumb__list li + li::before {
  content: "/ ";
  color: var(--muted);
}

.page-faq .breadcrumb a {
  color: var(--dim);
  text-decoration: none;
}

.page-faq .breadcrumb a:hover,
.page-faq .breadcrumb a:focus-visible {
  color: var(--accent);
  text-decoration: underline;
}

.page-faq .breadcrumb [aria-current="page"] {
  color: var(--accent);
}

.page-faq .faq-hero__kicker {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.12em;
  color: var(--dim);
}

.page-faq .faq-hero__title {
  margin: 10px 0 14px;
  max-width: 22ch;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(26px, 6.2vw, 44px);
  line-height: 1.16;
  letter-spacing: 0.02em;
  color: var(--ink);
}

.page-faq .faq-hero__lede {
  margin: 0;
  max-width: 58ch;
  font-size: var(--fs-16);
  line-height: 1.75;
  color: var(--dim);
}

.page-faq .faq-jump {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 22px;
}

.page-faq .faq-jump .chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 12px;
  font-size: var(--fs-12);
  line-height: 1.4;
  color: var(--dim);
  text-decoration: none;
  border: 1px solid var(--line);
  border-radius: var(--cut-sm);
  background: rgba(12, 31, 25, 0.72);
  transition: color 180ms ease, border-color 180ms ease, background-color 180ms ease;
}

.page-faq .faq-jump .chip .num {
  color: var(--data);
  font-size: var(--fs-12);
}

.page-faq .faq-jump .chip:hover,
.page-faq .faq-jump .chip:focus-visible {
  color: var(--ink);
  border-color: var(--accent);
  background: rgba(59, 240, 198, 0.12);
}

.page-faq .faq-hero__media {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 var(--pad-x) 30px;
}

.page-faq .faq-hero__media .media-frame {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  border: 1px solid var(--line);
  border-radius: var(--cut);
  background: var(--panel);
}

.page-faq .faq-hero__media .media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: repeating-linear-gradient(0deg, rgba(7, 19, 15, 0.22) 0 1px, transparent 1px 3px);
}

.page-faq .faq-hero__media img {
  position: absolute;
  inset: 0;
  display: block;
  width: 100%;
  height: 100%;
  max-width: 100%;
  object-fit: cover;
}

/* ---------- 主体两栏 ---------- */
.page-faq .faq-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 24px;
  padding-top: 30px;
  padding-bottom: 64px;
}

/* ---------- 左侧分类 ---------- */
.page-faq .faq-rail__title {
  display: none;
}

.page-faq .faq-rail__list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 6px;
  list-style: none;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.page-faq .faq-rail__item {
  flex: 0 0 auto;
}

.page-faq .faq-rail__link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 12px;
  white-space: nowrap;
  font-size: var(--fs-12);
  text-decoration: none;
  color: var(--dim);
  border: 1px solid var(--line);
  border-radius: var(--cut-sm);
  background: var(--panel);
  transition: color 180ms ease, border-color 180ms ease, background-color 180ms ease;
}

.page-faq .faq-rail__index {
  color: var(--data);
  font-size: var(--fs-12);
}

.page-faq .faq-rail__link:hover,
.page-faq .faq-rail__link:focus-visible {
  color: var(--ink);
  border-color: var(--accent);
}

.page-faq .faq-rail__item.is-current .faq-rail__link {
  color: var(--ink);
  border-color: var(--accent);
  background: rgba(59, 240, 198, 0.12);
}

.page-faq .faq-rail__hint {
  display: none;
}

/* ---------- 问题分组 ---------- */
.page-faq .faq-content {
  min-width: 0;
}

.page-faq .faq-group {
  scroll-margin-top: 84px;
}

.page-faq .faq-group + .faq-group {
  margin-top: 44px;
}

.page-faq .faq-group__head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  column-gap: 12px;
  align-items: baseline;
  padding-bottom: 10px;
  margin-bottom: 16px;
  border-bottom: 1px solid var(--line);
}

.page-faq .faq-group__index {
  font-size: var(--fs-14);
  color: var(--accent);
  letter-spacing: 0.08em;
}

.page-faq .faq-group__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: var(--fs-20);
  font-weight: 800;
  line-height: 1.3;
  letter-spacing: 0.03em;
  color: var(--ink);
}

.page-faq .faq-group__note {
  grid-column: 2;
  margin: 6px 0 0;
  font-size: var(--fs-12);
  line-height: 1.6;
  color: var(--dim);
}

/* ---------- 折叠问答 ---------- */
.page-faq .qa {
  position: relative;
  background: var(--card);
  border: 1px solid var(--line);
  border-left: 3px solid var(--muted);
  border-radius: 10px;
  overflow: hidden;
  transition: border-left-color 200ms ease, background-color 200ms ease;
}

.page-faq .qa + .qa {
  margin-top: 10px;
}

.page-faq .qa[open] {
  border-left-color: var(--accent);
  background: #143A2F;
}

.page-faq .qa__q {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 15px 16px;
  margin: 0;
  cursor: pointer;
  list-style: none;
  font-size: var(--fs-16);
  font-weight: 600;
  line-height: 1.55;
  color: var(--ink);
  transition: color 180ms ease;
}

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

.page-faq .qa__q::marker {
  content: "";
}

.page-faq .qa__q:hover,
.page-faq .qa__q:focus-visible {
  color: var(--accent);
}

.page-faq .qa__q:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: -2px;
}

.page-faq .qa__icon {
  position: relative;
  flex: 0 0 16px;
  width: 16px;
  height: 16px;
  margin-top: 4px;
  color: var(--accent);
}

.page-faq .qa__icon::before,
.page-faq .qa__icon::after {
  content: "";
  position: absolute;
  inset: 0;
  margin: auto;
  background: currentColor;
  transition: transform 200ms ease, opacity 200ms ease;
}

.page-faq .qa__icon::before {
  width: 14px;
  height: 1.5px;
}

.page-faq .qa__icon::after {
  width: 1.5px;
  height: 14px;
}

.page-faq .qa[open] .qa__icon::after {
  transform: rotate(180deg);
  opacity: 0;
}

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

.page-faq .qa__a {
  padding: 14px 16px 18px;
  border-top: 1px solid var(--line);
  font-size: var(--fs-14);
  line-height: 1.75;
  color: var(--dim);
}

.page-faq .qa__a p {
  margin: 0 0 10px;
}

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

.page-faq .qa__more a {
  display: inline-block;
  color: var(--accent);
  font-size: var(--fs-14);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-faq .qa__more a:hover,
.page-faq .qa__more a:focus-visible {
  text-decoration-thickness: 2px;
}

/* ---------- 章节配图 ---------- */
.page-faq .faq-figure {
  margin: 0 0 16px;
}

.page-faq .faq-figure .media-frame {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  border: 1px solid var(--line);
  border-radius: var(--cut);
  background: var(--panel);
}

.page-faq .faq-figure img {
  position: absolute;
  inset: 0;
  display: block;
  width: 100%;
  height: 100%;
  max-width: 100%;
  object-fit: cover;
  filter: saturate(0.92) contrast(1.04);
}

.page-faq .faq-figure__cap {
  margin: 10px 0 16px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.04em;
  color: var(--dim);
}

/* ---------- 平板及以上 ---------- */
@media (min-width: 720px) {
  .page-faq .faq-hero__media .media-frame {
    aspect-ratio: 3 / 1;
  }

  .page-faq .faq-hero__inner {
    padding-top: 34px;
    padding-bottom: 28px;
  }

  .page-faq .faq-hero__media {
    padding-bottom: 40px;
  }

  .page-faq .faq-figure .media-frame {
    aspect-ratio: 21 / 9;
  }
}

/* ---------- 桌面两栏骨架 ---------- */
@media (min-width: 900px) {
  .page-faq .faq-body {
    grid-template-columns: var(--faq-rail-w) minmax(0, 1fr);
    gap: var(--faq-rail-gap);
    padding-top: 44px;
    padding-bottom: 88px;
    align-items: start;
  }

  .page-faq .faq-rail {
    position: sticky;
    top: var(--faq-sticky-top);
  }

  .page-faq .faq-rail__title {
    display: block;
    margin: 0 0 12px;
    font-family: var(--font-mono);
    font-size: var(--fs-12);
    letter-spacing: 0.14em;
    color: var(--muted);
  }

  .page-faq .faq-rail__list {
    display: grid;
    gap: 2px;
    padding: 0;
    overflow: visible;
  }

  .page-faq .faq-rail__link {
    display: flex;
    width: 100%;
    padding: 10px 12px;
    white-space: normal;
    font-size: var(--fs-14);
    line-height: 1.5;
    color: var(--dim);
    border: 0;
    border-left: 2px solid transparent;
    border-radius: 0;
    background: transparent;
  }

  .page-faq .faq-rail__link:hover,
  .page-faq .faq-rail__link:focus-visible {
    color: var(--ink);
    background: var(--panel);
    border-color: var(--muted);
  }

  .page-faq .faq-rail__item.is-current .faq-rail__link {
    color: var(--ink);
    background: var(--panel);
    border-color: var(--accent);
  }

  .page-faq .faq-rail__index {
    font-size: var(--fs-12);
  }

  .page-faq .faq-rail__hint {
    display: block;
    margin-top: 22px;
    padding: 14px;
    border: 1px solid var(--line);
    border-radius: var(--cut-sm);
    background: var(--panel);
  }

  .page-faq .faq-rail__hint-text {
    margin: 0 0 10px;
    font-size: var(--fs-12);
    line-height: 1.65;
    color: var(--dim);
  }

  .page-faq .faq-group + .faq-group {
    margin-top: 56px;
  }

  .page-faq .qa__q {
    padding: 17px 20px;
    font-size: var(--fs-16);
  }

  .page-faq .qa__a {
    padding: 16px 20px 20px;
  }

  .page-faq .qa + .qa {
    margin-top: 12px;
  }
}

/* ---------- 大屏 ---------- */
@media (min-width: 1140px) {
  .page-faq {
    --faq-rail-w: 236px;
    --faq-rail-gap: 48px;
  }

  .page-faq .faq-group__title {
    font-size: var(--fs-28);
  }

  .page-faq .faq-hero__title {
    max-width: 24ch;
  }
}

/* ---------- 动效克制 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-faq .qa,
  .page-faq .qa__icon::before,
  .page-faq .qa__icon::after,
  .page-faq .faq-jump .chip,
  .page-faq .faq-rail__link {
    transition: none;
  }
}