.page-faq {
  --faq-rail-w: 264px;
  --faq-gap: clamp(16px, 2.6vw, 30px);
  position: relative;
  isolation: isolate;
}

/* ============ 首屏 ============ */
.page-faq .faq-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(40px, 7vw, 96px) 0 clamp(30px, 5vw, 60px);
  background:
    radial-gradient(120% 90% at 88% 0%, rgba(139, 92, 246, 0.16), transparent 58%),
    radial-gradient(90% 80% at 4% 12%, rgba(0, 229, 199, 0.12), transparent 60%);
}

.page-faq .faq-hero-art {
  position: absolute;
  top: -12%;
  right: -14%;
  width: min(720px, 76%);
  opacity: 0.28;
  pointer-events: none;
  z-index: -1;
  -webkit-mask-image: radial-gradient(closest-side at 60% 45%, #000 40%, transparent 82%);
  mask-image: radial-gradient(closest-side at 60% 45%, #000 40%, transparent 82%);
}

.page-faq .faq-hero-art img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: var(--r-lg);
  object-fit: cover;
}

.page-faq .faq-hero-inner {
  position: relative;
}

.page-faq .faq-hero .breadcrumb {
  margin-bottom: clamp(20px, 3.4vw, 40px);
}

.page-faq .faq-hero h1 {
  max-width: 19ch;
  margin: 12px 0 clamp(16px, 2.6vw, 24px);
  font-family: var(--f-sans);
  font-size: clamp(29px, 5.2vw, 60px);
  font-weight: 300;
  line-height: 1.14;
  letter-spacing: -0.012em;
  color: var(--text);
}

.page-faq .faq-hero h1::after {
  content: "";
  display: block;
  width: 88px;
  height: 3px;
  margin-top: clamp(18px, 2.6vw, 28px);
  border-radius: var(--r-pill);
  background: linear-gradient(90deg, var(--c-cyan), var(--c-violet) 55%, var(--c-coral));
}

.page-faq .faq-lede {
  max-width: 64ch;
  margin: 0 0 clamp(26px, 4vw, 44px);
  font-size: clamp(14.5px, 1.55vw, 17px);
  line-height: 1.9;
  color: var(--text-soft);
}

.page-faq .faq-facts {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 36px;
  margin: 0;
  padding: 22px 0 0;
  list-style: none;
  border-top: 1px solid var(--line-soft);
}

.page-faq .faq-facts li {
  display: flex;
  align-items: baseline;
  gap: 10px;
}

.page-faq .faq-facts .ff-key {
  font-family: var(--f-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--text-dim);
}

.page-faq .faq-facts strong {
  font-family: var(--f-mono);
  font-size: 13.5px;
  font-weight: 600;
  letter-spacing: 0.01em;
  color: var(--c-cyan);
}

/* ============ 主体面板 ============ */
.page-faq .faq-board {
  position: relative;
  padding: clamp(30px, 5vw, 60px) 0 clamp(60px, 9vw, 120px);
}

.page-faq .faq-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 48px);
}

/* ---- 左侧索引轨道 ---- */
.page-faq .faq-rail {
  min-width: 0;
}

.page-faq .faq-index {
  margin: 16px 0 0;
  padding: 0 0 0 2px;
  list-style: none;
  border-left: 1px solid var(--line-soft);
}

.page-faq .faq-index a {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-left: -1px;
  padding: 10px 0 10px 16px;
  border-left: 2px solid transparent;
  color: var(--text-soft);
  font-size: 14px;
  line-height: 1.5;
  text-decoration: none;
  transition: color 0.24s var(--ease), border-color 0.24s var(--ease);
}

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

.page-faq .faq-index .fidx {
  flex: none;
  font-family: var(--f-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--text-dim);
  transition: color 0.24s var(--ease);
}

.page-faq .faq-index a:hover .fidx {
  color: var(--c-coral);
}

.page-faq .faq-filter {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 24px;
  padding-top: 24px;
  border-top: 1px solid var(--line-soft);
}

.page-faq .faq-chip {
  appearance: none;
  padding: 7px 15px;
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  background: var(--bg-panel-soft);
  color: var(--text-soft);
  font-family: var(--f-sans);
  font-size: 12.5px;
  line-height: 1.4;
  letter-spacing: 0.04em;
  cursor: pointer;
  transition: color 0.24s var(--ease), border-color 0.24s var(--ease),
    background 0.24s var(--ease), box-shadow 0.24s var(--ease);
}

.page-faq .faq-chip:hover {
  color: var(--c-cyan);
  border-color: var(--line-cyan);
}

.page-faq .faq-chip:focus-visible {
  outline: 2px solid var(--c-violet);
  outline-offset: 3px;
}

.page-faq .faq-chip.is-on {
  color: var(--c-ink);
  border-color: transparent;
  background: linear-gradient(118deg, var(--c-cyan), var(--c-mist));
  box-shadow: 0 0 0 4px rgba(0, 229, 199, 0.12);
}

.page-faq .faq-rail-note {
  margin: 22px 0 0;
  padding: 15px 17px;
  border: 1px solid var(--line-soft);
  border-radius: var(--r-sm);
  background: var(--bg-panel-soft);
  color: var(--text-dim);
  font-size: 12.5px;
  line-height: 1.75;
}

/* ---- 右侧答案面板 ---- */
.page-faq .faq-panels {
  min-width: 0;
  padding: clamp(20px, 3.2vw, 42px);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background:
    linear-gradient(158deg, rgba(13, 43, 69, 0.78), rgba(7, 26, 43, 0.62) 58%, rgba(13, 43, 69, 0.5));
  box-shadow: 0 44px 130px -70px rgba(0, 229, 199, 0.32);
}

.page-faq .faq-group {
  scroll-margin-top: calc(var(--bar-h) + 30px);
}

.page-faq .faq-group + .faq-group {
  margin-top: clamp(30px, 4.6vw, 56px);
}

.page-faq .faq-group-head {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--line-soft);
}

.page-faq .faq-group-idx {
  flex: none;
  margin-top: 4px;
  padding: 5px 9px;
  border: 1px solid var(--line-cyan);
  border-radius: var(--r-xs);
  background: rgba(0, 229, 199, 0.08);
  color: var(--c-cyan);
  font-family: var(--f-mono);
  font-size: 12px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: 0.08em;
}

.page-faq .faq-group-meta {
  min-width: 0;
}

.page-faq .faq-group-title {
  margin: 0 0 6px;
  font-size: clamp(19px, 2.3vw, 25px);
  font-weight: 400;
  line-height: 1.3;
  letter-spacing: -0.006em;
  color: var(--text);
}

.page-faq .faq-group-sub {
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--text-dim);
}

.page-faq .faq-shot {
  margin: 20px 0 8px;
  max-width: 300px;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  background: rgba(7, 26, 43, 0.62);
}

.page-faq .faq-shot img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  border-radius: var(--r-sm);
  object-fit: cover;
}

.page-faq .faq-shot figcaption {
  margin-top: 10px;
  font-size: 12px;
  line-height: 1.65;
  letter-spacing: 0.02em;
  color: var(--text-dim);
}

/* ---- 折叠问答 ---- */
.page-faq .faq-list {
  min-width: 0;
}

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

.page-faq .faq-item:last-child {
  border-bottom: 0;
}

.page-faq .faq-item > summary {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 17px 0;
  list-style: none;
  cursor: pointer;
  color: var(--text);
  font-size: 15px;
  line-height: 1.65;
  transition: color 0.24s var(--ease);
}

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

.page-faq .faq-item > summary::before {
  content: "Q";
  flex: none;
  margin-top: 4px;
  font-family: var(--f-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--c-coral);
}

.page-faq .faq-item > summary::after {
  content: "";
  flex: none;
  width: 8px;
  height: 8px;
  margin: 8px 4px 0 auto;
  border-right: 1.6px solid var(--text-dim);
  border-bottom: 1.6px solid var(--text-dim);
  transform: rotate(45deg);
  transition: transform 0.3s var(--ease), border-color 0.26s var(--ease);
}

.page-faq .faq-item > summary:hover,
.page-faq .faq-item > summary:focus-visible {
  color: var(--c-cyan);
}

.page-faq .faq-item > summary:focus-visible {
  outline: 2px solid var(--c-violet);
  outline-offset: 2px;
  border-radius: var(--r-xs);
}

.page-faq .faq-item[open] > summary {
  color: var(--c-cyan);
}

.page-faq .faq-item[open] > summary::after {
  transform: rotate(-135deg);
  border-color: var(--c-cyan);
}

.page-faq .faq-answer {
  margin: 0 0 20px;
  padding: 2px 0 2px 16px;
  border-left: 2px solid rgba(255, 107, 74, 0.36);
  max-width: 68ch;
  font-size: 14.5px;
  line-height: 1.9;
  color: var(--text-soft);
}

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

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

.page-faq .faq-answer a {
  color: var(--c-cyan);
  text-decoration: none;
  border-bottom: 1px solid var(--line-cyan);
  transition: color 0.22s var(--ease), border-color 0.22s var(--ease);
}

.page-faq .faq-answer a:hover,
.page-faq .faq-answer a:focus-visible {
  color: var(--c-violet);
  border-bottom-color: var(--c-violet);
}

/* ============ 响应式 ============ */
@media (min-width: 720px) {
  .page-faq .faq-shot {
    max-width: 320px;
    float: right;
    margin: 4px 0 18px 26px;
  }
}

@media (min-width: 940px) {
  .page-faq .faq-layout {
    grid-template-columns: var(--faq-rail-w) minmax(0, 1fr);
    align-items: start;
  }

  .page-faq .faq-rail {
    position: sticky;
    top: calc(var(--bar-h) + 26px);
  }
}

@media (max-width: 719px) {
  .page-faq .faq-hero-art {
    top: -4%;
    right: -46%;
    width: 132%;
    opacity: 0.18;
  }

  .page-faq .faq-facts {
    gap: 10px 22px;
    padding-top: 18px;
  }

  .page-faq .faq-facts li {
    flex-direction: column;
    gap: 3px;
  }

  .page-faq .faq-panels {
    padding: 18px 16px;
    border-radius: var(--r-md);
  }

  .page-faq .faq-group-head {
    gap: 11px;
  }

  .page-faq .faq-item > summary {
    font-size: 14.5px;
    padding: 15px 0;
  }

  .page-faq .faq-answer {
    padding-left: 12px;
    font-size: 14px;
  }

  .page-faq .faq-shot {
    max-width: 100%;
    margin: 16px 0 4px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-faq .faq-item > summary::after,
  .page-faq .faq-chip,
  .page-faq .faq-index a {
    transition: none;
  }
}