.page-faq {
  --faq-rail: 220px;
  --faq-tick: 18px;
  position: relative;
  display: block;
  padding-bottom: clamp(56px, 9vw, 120px);
  background: var(--abyss);
  color: var(--fog);
}

/* ---------- 面包屑呼吸 ---------- */
.page-faq .breadcrumb {
  padding-block: clamp(16px, 3vw, 28px) 0;
}

/* ---------- 首屏框景 ---------- */
.page-faq .faq-hero {
  position: relative;
  padding: clamp(24px, 5vw, 56px) 0 clamp(32px, 6vw, 80px);
  border-bottom: 1px solid var(--line);
}

.page-faq .faq-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--violet) 20%, var(--magenta) 55%, transparent 92%);
  opacity: 0.55;
  pointer-events: none;
}

.page-faq .faq-hero__inner {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(24px, 4vw, 48px);
  align-items: center;
}

.page-faq .faq-hero__copy,
.page-faq .faq-hero__media {
  grid-column: 1 / -1;
  min-width: 0;
}

.page-faq .faq-hero__copy .coord {
  margin: 0 0 14px;
  color: var(--cyan);
}

.page-faq .faq-hero__copy h1 {
  margin: 0 0 18px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(30px, 8vw, 62px);
  line-height: 1.06;
  letter-spacing: -0.02em;
  color: var(--fog);
  text-shadow: 0 0 22px rgba(122, 59, 255, 0.55);
}

.page-faq .faq-hero__lead {
  margin: 0 0 26px;
  max-width: 44ch;
  font-size: 15px;
  line-height: 1.75;
  color: var(--fog-dim);
}

.page-faq .faq-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-faq .faq-hero__media {
  aspect-ratio: 2 / 1;
  border: 1px solid var(--line);
  overflow: hidden;
}

.page-faq .faq-hero__media img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* ---------- 双栏骨架 ---------- */
.page-faq .faq-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 4vw, 44px);
  padding-top: clamp(28px, 5vw, 56px);
}

/* ---------- 左侧索引 ---------- */
.page-faq .faq-rail {
  border-block: 1px solid var(--line);
  padding-block: 12px;
}

.page-faq .faq-rail__label {
  margin: 0 0 8px;
  color: var(--violet);
}

.page-faq .faq-rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: row;
  gap: 8px;
  overflow-x: auto;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
}

.page-faq .faq-rail__link {
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 8px 10px;
  white-space: nowrap;
  scroll-snap-align: start;
  font-size: 14px;
  color: var(--fog-dim);
  text-decoration: none;
  border: 1px solid transparent;
  transition: color 0.25s var(--ease), border-color 0.25s var(--ease), background 0.25s var(--ease);
}

.page-faq .faq-rail__link:hover,
.page-faq .faq-rail__link:focus-visible {
  color: var(--fog);
  background: var(--graphite);
  border-color: var(--line);
  outline: none;
}

.page-faq .faq-rail__num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--violet);
}

/* ---------- 右侧问答流 ---------- */
.page-faq .faq-stream {
  min-width: 0;
}

.page-faq .faq-group {
  padding-block: clamp(26px, 4.5vw, 52px);
  border-top: 1px solid var(--line);
  scroll-margin-top: 96px;
}

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

.page-faq .faq-group__head {
  position: relative;
  padding-left: var(--faq-tick);
  margin-bottom: clamp(16px, 3vw, 26px);
}

.page-faq .faq-group__head::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan), rgba(47, 243, 216, 0));
}

.page-faq .faq-group__head .coord {
  margin: 0 0 6px;
  color: var(--violet);
}

.page-faq .faq-group__head .section-title {
  margin: 0 0 6px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(21px, 4.6vw, 32px);
  line-height: 1.2;
  letter-spacing: -0.015em;
  color: var(--fog);
}

.page-faq .faq-group__head .section-note {
  margin: 0;
  font-size: 13px;
  color: var(--fog-dim);
}

.page-faq .faq-group__body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(18px, 3vw, 28px);
}

/* ---------- 手风琴条目 ---------- */
.page-faq .faq-items {
  display: flex;
  flex-direction: column;
}

.page-faq .faq-item {
  position: relative;
  padding-left: var(--faq-tick);
  border-left: 1px solid var(--line);
  border-bottom: 1px solid var(--line-soft);
  transition: border-left-color 0.35s var(--ease);
}

.page-faq .faq-item[open] {
  border-left-color: var(--cyan);
}

.page-faq .faq-item summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 16px 0;
  font-size: 15px;
  font-weight: 600;
  line-height: 1.5;
  color: var(--fog);
  transition: color 0.25s var(--ease);
}

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

.page-faq .faq-item summary:hover,
.page-faq .faq-item summary:focus-visible {
  color: var(--cyan);
  outline: none;
}

.page-faq .faq-item summary:focus-visible {
  box-shadow: inset 2px 0 0 0 var(--cyan);
}

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

.page-faq .faq-item__sign {
  position: relative;
  flex: 0 0 auto;
  width: 14px;
  height: 14px;
}

.page-faq .faq-item__sign::before,
.page-faq .faq-item__sign::after {
  content: "";
  position: absolute;
  background: var(--cyan);
  transition: transform 0.3s var(--ease), opacity 0.3s var(--ease);
}

.page-faq .faq-item__sign::before {
  top: 6px;
  left: 0;
  width: 14px;
  height: 1px;
}

.page-faq .faq-item__sign::after {
  left: 6px;
  top: 0;
  width: 1px;
  height: 14px;
}

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

.page-faq .faq-item__a {
  padding: 0 0 18px;
  max-width: 62ch;
}

.page-faq .faq-item__a p {
  margin: 0 0 8px;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--fog-dim);
}

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

.page-faq .faq-link {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(47, 243, 216, 0.4);
  transition: border-bottom-color 0.25s var(--ease), color 0.25s var(--ease);
}

.page-faq .faq-link:hover,
.page-faq .faq-link:focus-visible {
  color: var(--fog);
  border-bottom-color: var(--cyan);
  outline: none;
}

/* ---------- 路线图 ---------- */
.page-faq .faq-map {
  position: relative;
  aspect-ratio: 3 / 2;
  border: 1px solid var(--line);
  overflow: hidden;
  margin: 0;
}

.page-faq .faq-map img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.page-faq .faq-map__cap {
  position: absolute;
  left: 0;
  bottom: 0;
  right: 0;
  margin: 0;
  padding: 10px 14px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.04em;
  color: var(--fog);
  background: linear-gradient(180deg, rgba(6, 5, 10, 0) 0%, rgba(6, 5, 10, 0.9) 60%);
}

/* ---------- 排障链路 ---------- */
.page-faq .faq-chain {
  list-style: none;
  margin: clamp(16px, 3vw, 24px) 0 0;
  padding: 14px 0 0;
  border-top: 1px dashed var(--line);
  display: flex;
  flex-wrap: wrap;
  gap: 14px 34px;
}

.page-faq .faq-chain__node {
  position: relative;
  padding: 8px 14px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: var(--fog);
  background: var(--graphite);
  border: 1px solid var(--line);
  cursor: default;
  transition: border-color 0.25s var(--ease), color 0.25s var(--ease);
}

.page-faq .faq-chain__node + .faq-chain__node::before {
  content: "";
  position: absolute;
  left: -27px;
  top: 50%;
  width: 20px;
  height: 1px;
  background: var(--violet);
  transform: translateY(-50%);
}

.page-faq .faq-chain__node:hover,
.page-faq .faq-chain__node:focus-visible {
  border-color: var(--cyan);
  color: var(--cyan);
  outline: none;
}

.page-faq .faq-chain__node::after {
  content: attr(data-tip);
  position: absolute;
  left: 0;
  bottom: calc(100% + 8px);
  max-width: 220px;
  padding: 6px 10px;
  font-family: var(--font-body);
  font-size: 12px;
  line-height: 1.5;
  letter-spacing: 0;
  color: var(--fog);
  background: rgba(16, 13, 26, 0.96);
  border: 1px solid var(--line);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.22s var(--ease);
}

.page-faq .faq-chain__node:hover::after,
.page-faq .faq-chain__node:focus-visible::after {
  opacity: 1;
}

/* ---------- 人工协助 ---------- */
.page-faq .faq-group--final {
  border-top-color: var(--violet);
}

.page-faq .faq-help {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(18px, 3vw, 28px);
  scroll-margin-top: 96px;
}

.page-faq .faq-help__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.page-faq .faq-help__row {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  padding: 12px 14px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--fog-dim);
  background: var(--graphite);
  border-left: 1px solid var(--violet);
}

.page-faq .faq-help__idx {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--amber);
}

.page-faq .faq-help__panel {
  padding: clamp(16px, 3vw, 24px);
  background: linear-gradient(140deg, rgba(122, 59, 255, 0.16), rgba(255, 61, 156, 0.08) 70%, rgba(6, 5, 10, 0));
  border: 1px solid var(--line);
  border-top-color: var(--cyan);
}

.page-faq .faq-help__strong {
  margin: 0 0 12px;
  font-size: 15px;
  font-weight: 700;
  line-height: 1.6;
  color: var(--fog);
}

.page-faq .faq-help__line {
  margin: 0 0 10px;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--fog-dim);
}

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

/* ---------- 右下角辅助标签 ---------- */
.page-faq .faq-fab {
  position: fixed;
  right: clamp(12px, 2.5vw, 28px);
  bottom: clamp(12px, 2.5vw, 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: 0.06em;
  color: var(--cyan);
  text-decoration: none;
  background: rgba(16, 13, 26, 0.94);
  border: 1px solid var(--line);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 10px), calc(100% - 10px) 100%, 0 100%);
  transition: color 0.25s var(--ease), border-color 0.25s var(--ease);
}

.page-faq .faq-fab:hover,
.page-faq .faq-fab:focus-visible {
  color: var(--fog);
  border-color: var(--cyan);
  outline: none;
}

.page-faq .faq-fab__dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 8px var(--cyan);
}

/* ---------- 中等屏幕 ---------- */
@media (min-width: 700px) {
  .page-faq .faq-group__body {
    grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr);
    align-items: start;
    gap: clamp(20px, 3.5vw, 36px);
  }

  .page-faq .faq-help {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: start;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 960px) {
  .page-faq .faq-hero__copy {
    grid-column: 1 / span 6;
  }

  .page-faq .faq-hero__media {
    grid-column: 6 / span 7;
    margin-top: 52px;
  }

  .page-faq .faq-body {
    grid-template-columns: var(--faq-rail) minmax(0, 1fr);
    gap: clamp(32px, 5vw, 72px);
  }

  .page-faq .faq-rail {
    position: sticky;
    top: 104px;
    align-self: start;
    border-block: 0;
    border-left: 1px solid var(--line);
    padding: 4px 0 4px 16px;
  }

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

  .page-faq .faq-rail__link {
    white-space: normal;
    padding: 9px 10px;
  }

  .page-faq .faq-item summary {
    font-size: 15.5px;
    padding: 18px 0;
  }
}

@media (min-width: 1200px) {
  .page-faq .faq-hero__lead {
    font-size: 16px;
  }

  .page-faq .faq-item__a p {
    font-size: 15px;
  }
}

/* ---------- 减少动态 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-faq .faq-item,
  .page-faq .faq-item__sign::before,
  .page-faq .faq-item__sign::after,
  .page-faq .faq-rail__link,
  .page-faq .faq-chain__node,
  .page-faq .faq-chain__node::after,
  .page-faq .faq-link,
  .page-faq .faq-fab {
    transition: none;
  }
}
</main>