.page-faq {
  --faq-rule: 2px solid var(--grid);
  --faq-lead: clamp(14px, 2vw, 22px);
}

/* ── 首屏 ─────────────────────────────── */
.page-faq .faq-hero {
  position: relative;
  padding: clamp(20px, 3.5vw, 38px) 0 clamp(26px, 4.2vw, 50px);
  border-bottom: var(--faq-rule);
  overflow: hidden;
}

.page-faq .faq-hero::before {
  content: "";
  position: absolute;
  inset: -24% -12% 0 -12%;
  background-image:
    linear-gradient(to right, rgba(30, 58, 51, 0.85) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(30, 58, 51, 0.85) 1px, transparent 1px);
  background-size: 72px 72px;
  -webkit-mask-image: radial-gradient(130% 95% at 12% 0%, #000 0%, transparent 74%);
  mask-image: radial-gradient(130% 95% at 12% 0%, #000 0%, transparent 74%);
  pointer-events: none;
}

.page-faq .faq-hero > * {
  position: relative;
  z-index: 1;
}

.page-faq .faq-hero-kicker {
  margin: 0 0 clamp(14px, 2vw, 20px);
}

.page-faq .faq-hero-title {
  position: relative;
  margin: 0;
  padding-left: var(--faq-lead);
  max-width: 24ch;
  font-size: clamp(1.7rem, 5vw, 3.15rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.14;
  color: var(--white);
}

.page-faq .faq-hero-title::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.16em;
  bottom: 0.16em;
  width: 6px;
  background: linear-gradient(to bottom, var(--cyan), var(--gold));
}

.page-faq .faq-hero-lede {
  margin: clamp(14px, 2vw, 20px) 0 0 var(--faq-lead);
  max-width: 64ch;
  font-size: var(--fs-17);
  line-height: 1.82;
  color: rgba(234, 247, 243, 0.82);
}

/* ── 主体双栏 ──────────────────────────── */
.page-faq .faq-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 3.4vw, 42px);
  align-items: start;
  padding-top: clamp(24px, 3.8vw, 50px);
  padding-bottom: clamp(40px, 6vw, 88px);
}

/* ── 分类索引 ──────────────────────────── */
.page-faq .faq-index {
  min-width: 0;
}

.page-faq .faq-index-title {
  margin: 0 0 12px;
  padding-bottom: 8px;
  border-bottom: var(--faq-rule);
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--mist);
}

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

.page-faq .faq-index-list > li {
  flex: none;
}

.page-faq .faq-index-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border: var(--faq-rule);
  background: var(--carbon);
  color: var(--mist);
  font-size: var(--fs-14);
  font-weight: 700;
  white-space: nowrap;
  text-decoration: none;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease), background-color 0.18s var(--ease);
}

.page-faq .faq-index-link .num {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.08em;
  color: var(--gold);
}

.page-faq .faq-index-link:hover,
.page-faq .faq-index-link:focus-visible {
  color: var(--cyan);
  border-color: var(--cyan);
  background: rgba(53, 242, 208, 0.08);
}

.page-faq .faq-index-link:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
}

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

.page-faq .faq-group {
  min-width: 0;
  scroll-margin-top: 96px;
}

.page-faq .faq-group + .faq-group {
  margin-top: clamp(34px, 5vw, 60px);
}

.page-faq .faq-group-head {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 14px;
  padding: 12px 0 12px 16px;
  border-top: var(--faq-rule);
  border-bottom: var(--faq-rule);
}

.page-faq .faq-group-head::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  bottom: 10px;
  width: 5px;
  background: var(--cyan);
}

.page-faq .faq-group-index {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  color: var(--gold);
}

.page-faq .faq-group-title {
  margin: 0;
  font-size: clamp(1.1rem, 2.4vw, 1.6rem);
  font-weight: 800;
  letter-spacing: -0.01em;
  line-height: 1.3;
  color: var(--white);
}

.page-faq .faq-group-note {
  margin: 0 0 0 auto;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.04em;
  color: var(--mist);
}

/* ── 手风琴 ───────────────────────────── */
.page-faq .faq-list {
  margin-top: 2px;
}

.page-faq .faq-item {
  border-bottom: var(--faq-rule);
}

.page-faq .faq-q {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 15px 4px 15px 14px;
  cursor: pointer;
  list-style: none;
  font-size: var(--fs-17);
  font-weight: 700;
  line-height: 1.55;
  color: var(--white);
  transition: color 0.18s var(--ease), background-color 0.18s var(--ease);
}

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

.page-faq .faq-q:hover {
  color: var(--cyan);
  background: rgba(53, 242, 208, 0.04);
}

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

.page-faq .faq-q-num {
  flex: none;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.08em;
  color: var(--gold);
}

.page-faq .faq-q-text {
  min-width: 0;
}

.page-faq .faq-q::after {
  content: "+";
  flex: none;
  margin-left: auto;
  padding-left: 12px;
  font-family: var(--font-mono);
  font-size: var(--fs-22);
  font-weight: 400;
  line-height: 1;
  color: var(--cyan);
  transition: color 0.2s var(--ease);
}

.page-faq .faq-item[open] > .faq-q::after {
  content: "−";
  color: var(--gold);
}

.page-faq .faq-a {
  margin: 0 4px 0 14px;
  padding: 2px 0 20px 16px;
  border-left: 3px solid rgba(53, 242, 208, 0.5);
}

.page-faq .faq-a p {
  margin: 0 0 10px;
  max-width: 68ch;
  font-size: var(--fs-17);
  line-height: 1.78;
  color: rgba(234, 247, 243, 0.85);
}

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

.page-faq .faq-a a {
  color: var(--cyan);
  text-decoration: underline;
  text-decoration-color: rgba(53, 242, 208, 0.45);
  text-underline-offset: 3px;
}

.page-faq .faq-a a:hover {
  text-decoration-color: var(--cyan);
}

/* ── 插图 ─────────────────────────────── */
.page-faq .faq-figure {
  margin: clamp(22px, 3vw, 34px) 0 0;
  border: var(--faq-rule);
  background: var(--carbon);
  box-shadow: var(--shadow-hard);
}

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

.page-faq .faq-figure figcaption {
  padding: 10px 14px;
  border-top: var(--faq-rule);
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  line-height: 1.65;
  color: var(--mist);
}

/* ── 收尾入口 ──────────────────────────── */
.page-faq .faq-cta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px 24px;
  margin-top: clamp(32px, 4.5vw, 56px);
  padding: clamp(18px, 2.6vw, 30px);
  border: 2px solid var(--cyan);
  background:
    linear-gradient(135deg, rgba(53, 242, 208, 0.1), rgba(10, 31, 26, 0) 64%),
    var(--ink-2);
  box-shadow: var(--shadow-hard);
}

.page-faq .faq-cta-text {
  flex: 1 1 260px;
  min-width: 0;
  margin: 0;
  font-size: var(--fs-17);
  line-height: 1.72;
  color: var(--white);
}

/* ── 桌面端 ───────────────────────────── */
@media (min-width: 900px) {
  .page-faq .faq-body {
    grid-template-columns: 236px minmax(0, 1fr);
    gap: clamp(34px, 4vw, 64px);
  }

  .page-faq .faq-index {
    position: sticky;
    top: 96px;
  }

  .page-faq .faq-index-list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding-bottom: 0;
    border-top: var(--faq-rule);
  }

  .page-faq .faq-index-link {
    width: 100%;
    justify-content: flex-start;
    padding: 11px 6px;
    border: none;
    border-bottom: var(--faq-rule);
    background: transparent;
  }

  .page-faq .faq-index-link:hover,
  .page-faq .faq-index-link:focus-visible {
    background: rgba(53, 242, 208, 0.06);
  }

  .page-faq .faq-q {
    padding: 17px 8px 17px 16px;
  }

  .page-faq .faq-a {
    margin-left: 16px;
    padding-left: 20px;
  }

  .page-faq .faq-figure--tall {
    max-width: 560px;
  }
}

@media (min-width: 1280px) {
  .page-faq .faq-hero-title {
    max-width: 22ch;
  }

  .page-faq .faq-group-note {
    text-align: right;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-faq .faq-q,
  .page-faq .faq-q::after,
  .page-faq .faq-index-link {
    transition: none;
  }
}