.page-faq {
  --faq-rail-w: 236px;
  --faq-reveal: 260ms;
  background-color: var(--ink-900);
  color: var(--paper);
  font-family: var(--font-body);
  overflow-x: clip;
}

/* ---------- 面包屑 ---------- */
.page-faq .faq-crumbs {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 20px var(--gutter) 0;
}

/* ---------- 首屏 ---------- */
.page-faq .faq-hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
  padding: clamp(28px, 4vw, 52px) 0 0;
  background:
    radial-gradient(120% 140% at 88% 0%, rgba(58, 160, 255, 0.10), transparent 58%),
    var(--ink-900);
}

.page-faq .faq-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right, var(--line-soft) 1px, transparent 1px),
    linear-gradient(to bottom, var(--line-soft) 1px, transparent 1px);
  background-size: 88px 88px;
  opacity: 0.6;
}

.page-faq .faq-hero::after {
  content: "";
  position: absolute;
  top: -18%;
  right: -10%;
  width: 52%;
  height: 150%;
  z-index: 0;
  pointer-events: none;
  background: linear-gradient(150deg, var(--amber-soft), transparent 62%);
  clip-path: polygon(26% 0, 100% 0, 100% 100%, 0 100%);
}

.page-faq .faq-hero__art {
  position: absolute;
  top: 0;
  right: 0;
  z-index: 0;
  width: clamp(240px, 40vw, 560px);
  height: 100%;
  opacity: 0.3;
  pointer-events: none;
}

.page-faq .faq-hero__art img {
  display: block;
  width: 100%;
  height: 100%;
  max-width: 100%;
  object-fit: cover;
  object-position: top right;
  -webkit-mask-image: radial-gradient(120% 88% at 78% 18%, #000 18%, transparent 74%);
  mask-image: radial-gradient(120% 88% at 78% 18%, #000 18%, transparent 74%);
}

.page-faq .faq-hero__inner {
  position: relative;
  z-index: 2;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.page-faq .faq-hero h1 {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(36px, 6.4vw, 68px);
  line-height: 1.04;
  letter-spacing: -0.02em;
  color: var(--white);
}

.page-faq .faq-hero__sub {
  margin: 14px 0 0;
  font-family: var(--font-serif);
  font-weight: 500;
  font-size: clamp(15px, 2vw, 21px);
  line-height: 1.5;
  color: var(--amber);
  letter-spacing: 0.01em;
}

.page-faq .faq-hero__lede {
  margin: 20px 0 0;
  max-width: 58ch;
  color: var(--moss);
  font-size: clamp(14px, 1.7vw, 16px);
  line-height: 1.85;
}

/* ---------- 首屏分类索引 ---------- */
.page-faq .faq-index {
  position: relative;
  z-index: 2;
  max-width: var(--shell);
  margin: clamp(30px, 4vw, 52px) auto 0;
  padding: 0 var(--gutter) clamp(26px, 4vw, 46px);
  display: grid;
  gap: 10px;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
}

.page-faq .faq-index__item {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 10px;
  padding: 14px 16px;
  border: 1px solid var(--line-soft);
  border-left: 2px solid var(--amber-line);
  background-color: var(--ink-800);
  color: var(--paper);
  text-decoration: none;
  transition: background-color 0.2s ease, border-color 0.2s ease, transform 0.2s ease;
}

.page-faq .faq-index__item:hover,
.page-faq .faq-index__item:focus-visible {
  background-color: var(--ink-700);
  border-left-color: var(--amber);
  transform: translateY(-2px);
}

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

.page-faq .faq-index__name {
  flex: 1 1 120px;
  font-size: 14px;
  font-weight: 600;
  line-height: 1.5;
}

.page-faq .faq-index__count {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--grid);
}

/* ---------- 主体容器 ---------- */
.page-faq .faq-body {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 var(--gutter) clamp(48px, 7vw, 92px);
}

/* ---------- 左侧分类刻度（移动端为顶部横条） ---------- */
.page-faq .faq-rail {
  position: sticky;
  top: calc(var(--header-main-h) + 4px);
  z-index: 6;
  margin: 0 calc(var(--gutter) * -1);
  padding: 10px var(--gutter);
  background-color: rgba(7, 18, 14, 0.94);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
  overflow-x: auto;
  scrollbar-width: none;
}

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

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

.page-faq .faq-rail__nav {
  display: flex;
  gap: 8px;
  white-space: nowrap;
}

.page-faq .faq-rail__link {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border: 1px solid var(--line);
  color: var(--moss);
  font-size: 13px;
  line-height: 1.4;
  text-decoration: none;
  transition: color 0.2s ease, border-color 0.2s ease, background-color 0.2s ease;
}

.page-faq .faq-rail__link > span {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--grid);
  transition: color 0.2s ease;
}

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

.page-faq .faq-rail__link.is-active {
  color: var(--white);
  border-color: var(--blue);
  background-color: var(--blue-soft);
}

.page-faq .faq-rail__link.is-active > span {
  color: var(--blue);
}

/* ---------- 分类区块 ---------- */
.page-faq .faq-group {
  padding-top: clamp(38px, 5vw, 68px);
  scroll-margin-top: calc(var(--header-main-h) + 86px);
}

.page-faq .faq-main > .faq-group:first-child {
  padding-top: clamp(30px, 4vw, 54px);
}

.page-faq .faq-group__head {
  margin-bottom: clamp(18px, 2.6vw, 30px);
}

.page-faq .faq-group__head h2 {
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(23px, 3.4vw, 34px);
  line-height: 1.24;
  letter-spacing: -0.01em;
  color: var(--white);
}

.page-faq .faq-group__intro {
  margin: 12px 0 0;
  max-width: 62ch;
  color: var(--moss);
  font-size: 15px;
  line-height: 1.8;
}

.page-faq .faq-figure {
  margin: clamp(18px, 2.6vw, 0) 0 0;
}

.page-faq .faq-figure .media-frame {
  width: 100%;
}

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

/* ---------- 问答条目 ---------- */
.page-faq .faq-list {
  border-top: 1px solid var(--line);
}

.page-faq .faq-item {
  position: relative;
  border-bottom: 1px solid var(--line-soft);
  transition: background-color 0.25s ease, border-color 0.25s ease;
}

.page-faq .faq-item[open] {
  border-bottom-color: var(--line);
  background-color: var(--ink-800);
}

.page-faq .faq-item__q {
  position: relative;
  display: flex;
  align-items: flex-start;
  gap: 14px;
  padding: clamp(16px, 2.2vw, 22px) 14px clamp(16px, 2.2vw, 22px) 16px;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(15px, 1.8vw, 17px);
  line-height: 1.62;
  color: var(--paper);
  transition: color 0.2s ease;
}

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

.page-faq .faq-item__q::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background-color: transparent;
  transition: background-color 0.2s ease;
}

.page-faq .faq-item__q::after {
  content: "+";
  flex: 0 0 auto;
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 20px;
  line-height: 1.35;
  color: var(--amber);
  transition: color 0.2s ease;
}

.page-faq .faq-item:hover > .faq-item__q {
  color: var(--white);
}

.page-faq .faq-item:hover > .faq-item__q::before {
  background-color: var(--amber-line);
}

.page-faq .faq-item[open] > .faq-item__q {
  color: var(--white);
}

.page-faq .faq-item[open] > .faq-item__q::before {
  background-color: var(--blue);
}

.page-faq .faq-item[open] > .faq-item__q::after {
  content: "–";
  color: var(--blue);
}

.page-faq .faq-item__a {
  padding: 0 clamp(14px, 2vw, 22px) clamp(18px, 2.4vw, 26px) 16px;
  max-width: 76ch;
}

.page-faq .faq-item__a p {
  margin: 0;
  color: var(--moss);
  font-size: 15px;
  line-height: 1.86;
}

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

.page-faq .faq-item__a a {
  color: var(--amber);
  text-decoration: none;
  border-bottom: 1px solid var(--amber-line);
  transition: border-color 0.2s ease, color 0.2s ease;
}

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

.page-faq .faq-key {
  font-family: var(--font-mono);
  font-size: 1.08em;
  font-variant-numeric: tabular-nums;
  color: var(--amber);
}

.page-faq .faq-item__meta {
  display: block;
  margin-top: 14px;
  padding-top: 10px;
  border-top: 1px dashed var(--line-soft);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--grid);
}

.page-faq .faq-item[open] > .faq-item__a {
  animation: faq-reveal var(--faq-reveal) ease-out both;
}

@keyframes faq-reveal {
  from {
    opacity: 0;
    transform: translateY(-6px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ---------- 页尾行动带 ---------- */
.page-faq .faq-cta {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  border-top: 1px solid var(--line);
  background: linear-gradient(118deg, var(--ink-800) 0%, var(--ink-900) 66%);
}

.page-faq .faq-cta::after {
  content: "";
  position: absolute;
  right: -8%;
  top: -42%;
  width: 46%;
  height: 190%;
  z-index: 0;
  pointer-events: none;
  background: var(--amber-soft);
  clip-path: polygon(38% 0, 100% 0, 100% 100%, 0 100%);
}

.page-faq .faq-cta__inner {
  position: relative;
  z-index: 1;
  max-width: var(--shell);
  margin: 0 auto;
  padding: clamp(36px, 5vw, 68px) var(--gutter);
}

.page-faq .faq-cta h2 {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(22px, 3.2vw, 34px);
  line-height: 1.24;
  letter-spacing: -0.01em;
  color: var(--white);
}

.page-faq .faq-cta p {
  margin: 12px 0 0;
  max-width: 58ch;
  color: var(--moss);
  font-size: 15px;
  line-height: 1.8;
}

.page-faq .faq-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

/* ---------- 桌面端栅格 ---------- */
@media (min-width: 960px) {
  .page-faq .faq-body {
    display: grid;
    grid-template-columns: var(--faq-rail-w) minmax(0, 1fr);
    gap: clamp(30px, 4vw, 64px);
    align-items: start;
    padding-top: clamp(38px, 5vw, 72px);
  }

  .page-faq .faq-rail {
    position: sticky;
    top: calc(var(--header-main-h) + 26px);
    margin: 0;
    padding: 0;
    background: none;
    -webkit-backdrop-filter: none;
    backdrop-filter: none;
    border-bottom: 0;
    overflow: visible;
  }

  .page-faq .faq-rail__title {
    display: block;
    margin: 0 0 14px;
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--grid);
  }

  .page-faq .faq-rail__nav {
    display: flex;
    flex-direction: column;
    gap: 0;
    white-space: normal;
    border-left: 1px solid var(--line);
  }

  .page-faq .faq-rail__link {
    position: relative;
    display: flex;
    align-items: baseline;
    gap: 10px;
    border: 0;
    background: none;
    padding: 10px 12px;
    font-size: 14px;
    line-height: 1.5;
    white-space: normal;
  }

  .page-faq .faq-rail__link::before {
    content: "";
    position: absolute;
    left: -1px;
    top: 8px;
    bottom: 8px;
    width: 2px;
    background-color: transparent;
    transition: background-color 0.2s ease;
  }

  .page-faq .faq-rail__link:hover {
    border-color: transparent;
    color: var(--paper);
  }

  .page-faq .faq-rail__link.is-active {
    background: none;
    border-color: transparent;
    color: var(--white);
  }

  .page-faq .faq-rail__link.is-active::before {
    background-color: var(--blue);
  }

  .page-faq .faq-group__head--split {
    display: grid;
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    gap: clamp(26px, 4vw, 52px);
    align-items: center;
  }

  .page-faq .faq-group__head--split .faq-figure {
    margin-top: 0;
  }

  .page-faq .faq-item__q {
    padding-right: 22px;
  }
}

@media (min-width: 1280px) {
  .page-faq .faq-hero__lede {
    font-size: 17px;
  }
}

/* ---------- 动效降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-faq .faq-index__item,
  .page-faq .faq-item,
  .page-faq .faq-item__q,
  .page-faq .faq-rail__link {
    transition: none;
  }

  .page-faq .faq-index__item:hover {
    transform: none;
  }

  .page-faq .faq-item[open] > .faq-item__a {
    animation: none;
  }
}