.page-faq {
  --faq-gap: clamp(32px, 5vw, 72px);
  --faq-line: var(--ink-800);
  display: block;
  padding-bottom: clamp(96px, 12vw, 140px);
  background-image: radial-gradient(circle at 82% 4%, rgba(53, 224, 208, .07) 0%, rgba(7, 11, 20, 0) 46%);
}

/* ---------- 首屏 ---------- */
.page-faq .faq-hero {
  padding-top: clamp(20px, 3.5vw, 44px);
}

.page-faq .crumb {
  margin-bottom: clamp(16px, 2.6vw, 26px);
}

.page-faq .crumb__item {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 12px;
  color: var(--rock-400);
}

.page-faq .crumb__item a {
  color: var(--rock-400);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--dur-fast) var(--ease-out), border-color var(--dur-fast) var(--ease-out);
}

.page-faq .crumb__item a:hover,
.page-faq .crumb__item a:focus-visible {
  color: var(--signal-cyan);
  border-bottom-color: var(--signal-cyan);
}

.page-faq .crumb__sep {
  color: var(--ink-800);
}

.page-faq .faq-hero__frame {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 48px);
  padding: clamp(26px, 4vw, 52px) clamp(20px, 3.4vw, 48px) clamp(28px, 4vw, 52px);
  border: 1px solid var(--faq-line);
  background: linear-gradient(180deg, rgba(20, 30, 48, .74) 0%, rgba(7, 11, 20, .18) 100%);
  box-shadow: 6px 6px 0 rgba(184, 122, 84, .1);
}

.page-faq .faq-hero__frame::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 6px;
  background-image: repeating-linear-gradient(90deg, var(--ink-800) 0 1px, transparent 1px 14px);
  pointer-events: none;
}

.page-faq .faq-hero__copy {
  display: grid;
  gap: 14px;
  align-content: start;
}

.page-faq .faq-hero__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(27px, 4.4vw, 50px);
  line-height: 1.14;
  letter-spacing: .04em;
  color: var(--rock-100);
}

.page-faq .lede {
  margin: 0;
  max-width: 36em;
  color: var(--rock-400);
}

.page-faq .faq-hero__contact {
  margin: 4px 0 0;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  font-size: 13px;
  color: var(--rock-400);
}

.page-faq .faq-hero__contact a {
  color: var(--signal-cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(53, 224, 208, .35);
  transition: color var(--dur-fast) var(--ease-out), border-color var(--dur-fast) var(--ease-out);
}

.page-faq .faq-hero__contact a:hover,
.page-faq .faq-hero__contact a:focus-visible {
  color: var(--paper);
  border-bottom-color: var(--paper);
}

.page-faq .faq-hero__sep {
  color: var(--ink-800);
}

.page-faq .faq-hero__media {
  margin: 0;
  border: 1px solid var(--faq-line);
  background: repeating-linear-gradient(135deg, rgba(26, 36, 54, .62) 0 10px, rgba(14, 22, 38, .62) 10px 20px);
  overflow: hidden;
}

.page-faq .faq-hero__media img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
}

.page-faq .faq-hero__media figcaption {
  padding: 10px 14px;
  border-top: 1px solid var(--faq-line);
  font-size: 12px;
  color: var(--rock-400);
}

/* ---------- 分组索引条 ---------- */
.page-faq .faq-index {
  margin-top: clamp(18px, 2.6vw, 28px);
  padding: 16px clamp(18px, 3vw, 30px) 18px;
  border: 1px solid var(--faq-line);
  background: var(--ink-900);
}

.page-faq .faq-index__label {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--rock-400);
}

.page-faq .faq-index__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 26px;
}

.page-faq .faq-index__list a {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 4px 0;
  font-size: 14px;
  color: var(--rock-100);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--dur-fast) var(--ease-out), border-color var(--dur-fast) var(--ease-out);
}

.page-faq .faq-index__list a:hover,
.page-faq .faq-index__list a:focus-visible {
  color: var(--signal-cyan);
  border-bottom-color: var(--signal-cyan);
}

.page-faq .faq-index__list .num {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--signal-cyan);
}

/* ---------- 主体骨架 ---------- */
.page-faq .faq-body {
  margin-top: var(--faq-gap);
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 4vw, 48px);
}

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

.page-faq .faq-groups {
  display: grid;
  gap: clamp(22px, 3vw, 38px);
  min-width: 0;
}

/* ---------- 问答分组 ---------- */
.page-faq .faq-group {
  position: relative;
  padding: clamp(20px, 3vw, 34px) clamp(16px, 3vw, 34px) clamp(22px, 3vw, 36px) clamp(16px, 3vw, 28px);
  border-left: 3px solid var(--ink-800);
  background: linear-gradient(180deg, rgba(20, 30, 48, .52) 0%, rgba(7, 11, 20, 0) 68%);
  scroll-margin-top: calc(var(--header-h) + 28px);
  transition: border-color var(--dur-mid) var(--ease-out);
}

.page-faq .faq-group:has(details[open]) {
  border-left-color: var(--signal-cyan);
}

.page-faq .faq-group__head {
  display: grid;
  gap: 6px;
  margin-bottom: clamp(14px, 2vw, 22px);
}

.page-faq .faq-group__index {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--signal-cyan);
}

.page-faq .faq-group__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(20px, 2.6vw, 28px);
  line-height: 1.26;
  letter-spacing: .04em;
  color: var(--rock-100);
}

.page-faq .faq-group__hint {
  margin: 0;
  font-size: 13px;
  line-height: 1.6;
  color: var(--rock-400);
}

/* ---------- 可展开内容组 ---------- */
.page-faq .q {
  border-top: 1px solid var(--faq-line);
}

.page-faq .q:last-of-type {
  border-bottom: 1px solid var(--faq-line);
}

.page-faq .q > summary {
  position: relative;
  list-style: none;
  cursor: pointer;
  padding: 15px 42px 15px 14px;
  border-left: 2px solid transparent;
  font-size: 15px;
  font-weight: 600;
  line-height: 1.55;
  color: var(--rock-100);
  transition: color var(--dur-fast) var(--ease-out),
              border-color var(--dur-fast) var(--ease-out),
              background-color var(--dur-fast) var(--ease-out);
}

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

.page-faq .q > summary::marker {
  content: "";
}

.page-faq .q > summary::after {
  content: "";
  position: absolute;
  right: 14px;
  top: 50%;
  width: 8px;
  height: 8px;
  margin-top: -6px;
  border-right: 2px solid currentColor;
  border-bottom: 2px solid currentColor;
  transform: rotate(45deg);
  transition: transform var(--dur-mid) var(--ease-out), margin-top var(--dur-mid) var(--ease-out);
}

.page-faq .q > summary:hover {
  color: var(--paper);
  background: rgba(53, 224, 208, .06);
}

.page-faq .q > summary:focus-visible {
  outline: 1px solid var(--signal-cyan);
  outline-offset: -1px;
}

.page-faq .q[open] > summary {
  color: var(--paper);
  border-left-color: var(--signal-cyan);
  background: rgba(53, 224, 208, .05);
}

.page-faq .q[open] > summary::after {
  margin-top: -2px;
  transform: rotate(-135deg);
}

.page-faq .q__body {
  padding: 2px 42px 20px 16px;
  font-size: 14.5px;
  line-height: 1.74;
  color: var(--rock-400);
}

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

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

.page-faq .q__body a {
  color: var(--signal-cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(53, 224, 208, .35);
}

.page-faq .q__body a:hover,
.page-faq .q__body a:focus-visible {
  color: var(--paper);
  border-bottom-color: var(--paper);
}

.page-faq .q__body .num {
  font-family: var(--font-mono);
  color: var(--rock-100);
}

/* ---------- 步骤列表 ---------- */
.page-faq .steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 9px;
  counter-reset: faqstep;
}

.page-faq .steps > li {
  display: grid;
  grid-template-columns: 30px minmax(0, 1fr);
  gap: 10px;
  align-items: start;
}

.page-faq .steps > li::before {
  counter-increment: faqstep;
  content: counter(faqstep, decimal-leading-zero);
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 20px;
  text-align: center;
  color: var(--signal-cyan);
  border: 1px solid var(--ink-800);
}

/* ---------- 组内配图 ---------- */
.page-faq .faq-figure {
  margin: clamp(18px, 2.6vw, 26px) 0 0;
  max-width: 540px;
  border: 1px solid var(--faq-line);
  background: rgba(14, 22, 38, .7);
  overflow: hidden;
}

.page-faq .faq-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
}

.page-faq .faq-figure figcaption {
  padding: 10px 14px;
  border-top: 1px solid var(--faq-line);
  font-size: 12px;
  line-height: 1.6;
  color: var(--rock-400);
}

/* ---------- 底部指引 ---------- */
.page-faq .faq-outro {
  display: grid;
  gap: 10px;
  padding: clamp(20px, 3vw, 32px) clamp(18px, 3vw, 32px);
  border: 1px solid var(--faq-line);
  background: var(--ink-900);
}

.page-faq .faq-outro p {
  margin: 0;
  font-size: 14px;
  line-height: 1.72;
  color: var(--rock-400);
}

.page-faq .faq-outro a {
  color: var(--signal-cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(53, 224, 208, .38);
  transition: color var(--dur-fast) var(--ease-out), border-color var(--dur-fast) var(--ease-out);
}

.page-faq .faq-outro a:hover,
.page-faq .faq-outro a:focus-visible {
  color: var(--paper);
  border-bottom-color: var(--paper);
}

/* ---------- 固定回目录入口 ---------- */
.page-faq .faq-top {
  position: fixed;
  right: clamp(14px, 3vw, 28px);
  bottom: clamp(14px, 3vw, 28px);
  z-index: 30;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 16px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--ink-950);
  background: var(--paper);
  border: 1px solid var(--paper);
  text-decoration: none;
  box-shadow: 0 8px 22px rgba(0, 0, 0, .5);
  transition: background-color var(--dur-fast) var(--ease-out),
              color var(--dur-fast) var(--ease-out),
              border-color var(--dur-fast) var(--ease-out);
}

.page-faq .faq-top:hover,
.page-faq .faq-top:focus-visible {
  background: var(--signal-cyan);
  border-color: var(--signal-cyan);
  color: var(--ink-950);
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-faq .faq-hero__frame {
    grid-template-columns: minmax(0, 1.06fr) minmax(0, .94fr);
    align-items: start;
  }
}

@media (min-width: 1000px) {
  .page-faq .faq-body {
    grid-template-columns: 172px minmax(0, 1fr);
    gap: clamp(32px, 4vw, 60px);
  }

  .page-faq .faq-rail {
    display: block;
    position: sticky;
    top: calc(var(--header-h) + 26px);
    align-self: start;
  }

  .page-faq .faq-rail__title {
    margin: 0 0 14px;
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: .16em;
    color: var(--rock-400);
  }

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

  .page-faq .faq-rail__list a {
    display: block;
    padding: 8px 0 8px 12px;
    font-size: 13px;
    color: var(--rock-400);
    text-decoration: none;
    border-left: 1px solid var(--ink-800);
    transition: color var(--dur-fast) var(--ease-out), border-color var(--dur-fast) var(--ease-out);
  }

  .page-faq .faq-rail__list a:hover,
  .page-faq .faq-rail__list a:focus-visible {
    color: var(--signal-cyan);
    border-left-color: var(--signal-cyan);
  }
}

@media (max-width: 640px) {
  .page-faq .faq-hero__frame {
    padding: 20px 16px 24px;
    box-shadow: 4px 4px 0 rgba(184, 122, 84, .1);
  }

  .page-faq .faq-group {
    padding: 18px 14px 22px 16px;
    border-left-width: 2px;
  }

  .page-faq .q > summary {
    padding: 14px 36px 14px 12px;
    font-size: 14.5px;
  }

  .page-faq .q__body {
    padding: 2px 18px 18px 12px;
    font-size: 14px;
  }

  .page-faq .steps > li {
    grid-template-columns: 26px minmax(0, 1fr);
    gap: 8px;
  }

  .page-faq .faq-top {
    padding: 9px 13px;
    font-size: 11px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-faq .faq-group,
  .page-faq .q > summary,
  .page-faq .q > summary::after,
  .page-faq .faq-top,
  .page-faq .faq-index__list a,
  .page-faq .faq-rail__list a {
    transition: none;
  }
}