.page-faq {
  --faq-rail-w: 15.5rem;
  --faq-gap: clamp(1.6rem, 4.5vw, 3.5rem);
  --faq-radius: 2px;
  position: relative;
  overflow-x: clip;
  padding-bottom: 5.5rem;
}

/* ---------- 面包屑 ---------- */
.page-faq .crumbs {
  max-width: var(--shell-w);
  margin: 0 auto;
  padding: 1.35rem clamp(1rem, 4vw, 2rem) 0;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .5rem;
  font-family: var(--font-mono);
  font-size: .76rem;
  letter-spacing: .09em;
  color: var(--mist);
}

.page-faq .crumbs a {
  color: var(--mist);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .25s var(--ease), border-color .25s var(--ease);
}

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

.page-faq .crumbs__sep {
  color: var(--line-strong);
}

/* ---------- 首屏 ---------- */
.page-faq .faq-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(1.8rem, 5vw, 3.4rem) 0 clamp(2.2rem, 5vw, 3.4rem);
}

.page-faq .faq-hero__deco {
  position: absolute;
  top: -0.22em;
  right: -0.06em;
  font-family: var(--font-mono);
  font-weight: 800;
  font-size: clamp(5rem, 21vw, 15rem);
  line-height: .78;
  letter-spacing: -0.05em;
  color: rgba(143, 166, 196, .07);
  pointer-events: none;
  user-select: none;
  z-index: 0;
}

.page-faq .faq-hero__inner {
  position: relative;
  z-index: 1;
}

.page-faq .faq-hero__inner h1 {
  margin: .55rem 0 0;
  max-width: 20ch;
  font-size: clamp(2.1rem, 6.6vw, 4.6rem);
  line-height: 1.05;
  letter-spacing: -0.025em;
  color: var(--white);
}

.page-faq .faq-hero__inner .lede {
  margin: 1.15rem 0 0;
  max-width: 46ch;
  color: var(--mist);
  font-size: clamp(.98rem, 2.4vw, 1.08rem);
  line-height: 1.85;
}

.page-faq .faq-hero__acts {
  display: flex;
  flex-wrap: wrap;
  gap: .7rem;
  margin-top: clamp(1.4rem, 3.4vw, 2rem);
}

.page-faq .faq-hero__stats {
  margin-top: clamp(1.8rem, 4.5vw, 2.8rem);
}

.page-faq .faq-hero__stats .stat__v {
  font-family: var(--font-mono);
  letter-spacing: .02em;
}

/* ---------- 左索引 + 右内容 ---------- */
.page-faq .faq-walk {
  position: relative;
}

.page-faq .faq-walk__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--faq-gap);
}

.page-faq .faq-rail {
  border: 1px solid var(--line-soft);
  border-left: 3px solid var(--cyan);
  background: rgba(14, 42, 78, .55);
  padding: 1rem 1.1rem 1.15rem;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 16px), calc(100% - 16px) 100%, 0 100%);
}

.page-faq .faq-rail__title {
  margin: 0 0 .8rem;
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--mist);
}

.page-faq .faq-rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: .45rem;
}

.page-faq .faq-rail__link {
  display: inline-flex;
  align-items: center;
  gap: .5rem;
  padding: .42rem .7rem;
  border: 1px solid var(--line-soft);
  color: var(--white);
  font-size: .84rem;
  text-decoration: none;
  transition: border-color .25s var(--ease), background .25s var(--ease), color .25s var(--ease);
}

.page-faq .faq-rail__no {
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .06em;
  color: var(--cyan);
}

.page-faq .faq-rail__link:hover,
.page-faq .faq-rail__link:focus-visible {
  border-color: var(--cyan);
  background: rgba(46, 242, 200, .1);
}

.page-faq .faq-rail__note {
  margin: .95rem 0 0;
  font-size: .8rem;
  line-height: 1.7;
  color: var(--mist);
}

/* ---------- 内容区 ---------- */
.page-faq .faq-body__head {
  margin-bottom: clamp(1.3rem, 3.5vw, 2rem);
}

.page-faq .faq-body__head h2 {
  margin: .2rem 0 .5rem;
  font-size: clamp(1.5rem, 3.6vw, 2.35rem);
  letter-spacing: -0.015em;
  color: var(--white);
}

.page-faq .faq-body__head .lede {
  max-width: 40ch;
  color: var(--mist);
  line-height: 1.8;
}

/* ---------- 步骤卡 ---------- */
.page-faq .faq-step {
  position: relative;
  background: var(--deep);
  border: 2px solid var(--line);
  border-top-width: 3px;
  padding: clamp(1.25rem, 4vw, 2.1rem);
  margin-bottom: clamp(1rem, 2.8vw, 1.6rem);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 22px), calc(100% - 22px) 100%, 0 100%);
  transition: border-color .3s var(--ease), transform .3s var(--ease);
}

.page-faq .faq-step[data-tone="watch"] {
  --step-accent: var(--cyan);
  --step-band: var(--band-a);
}

.page-faq .faq-step[data-tone="price"] {
  --step-accent: var(--coral);
  --step-band: var(--band-c);
}

.page-faq .faq-step[data-tone="center"] {
  --step-accent: var(--violet);
  --step-band: var(--band-b);
}

.page-faq .faq-step {
  border-top-color: var(--step-accent);
}

.page-faq .faq-step::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 42%;
  height: 3px;
  background: var(--step-band);
}

.page-faq .faq-step:hover {
  border-color: var(--line-strong);
}

.page-faq .faq-step__head {
  display: flex;
  align-items: baseline;
  gap: .9rem;
  margin-bottom: .7rem;
}

.page-faq .faq-step__num {
  flex: none;
  font-family: var(--font-mono);
  font-size: clamp(2rem, 5.6vw, 3.1rem);
  font-weight: 800;
  line-height: .88;
  letter-spacing: -0.03em;
  color: var(--step-accent);
}

.page-faq .faq-step__title {
  margin: 0;
  font-size: clamp(1.08rem, 2.8vw, 1.4rem);
  line-height: 1.4;
  letter-spacing: -0.01em;
  color: var(--white);
}

.page-faq .faq-step .prose {
  color: var(--mist);
  line-height: 1.85;
  max-width: var(--measure);
}

.page-faq .faq-step__list {
  list-style: none;
  margin: 1rem 0 0;
  padding: 0;
  display: grid;
  gap: .7rem;
}

.page-faq .faq-step__list li {
  position: relative;
  padding-left: 1.15rem;
  font-size: .93rem;
  line-height: 1.8;
  color: var(--mist);
}

.page-faq .faq-step__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .72em;
  width: .5rem;
  height: 2px;
  background: var(--step-accent);
}

.page-faq .faq-step__list strong {
  color: var(--white);
  font-weight: 600;
}

.page-faq .faq-step__result {
  margin: 1.15rem 0 0;
  padding: .8rem 1rem;
  border-left: 2px solid var(--step-accent);
  background: rgba(4, 16, 31, .6);
  font-size: .89rem;
  line-height: 1.8;
  color: var(--mist);
}

.page-faq .faq-step__result strong {
  color: var(--step-accent);
  font-weight: 600;
}

/* ---------- 通用区块 ---------- */
.page-faq .faq-block {
  margin-top: clamp(2.6rem, 7vw, 4.5rem);
}

.page-faq .faq-block__head {
  margin-bottom: clamp(1.2rem, 3.4vw, 1.9rem);
}

.page-faq .faq-block__head h2 {
  margin: .3rem 0 .55rem;
  font-size: clamp(1.45rem, 3.5vw, 2.25rem);
  line-height: 1.15;
  letter-spacing: -0.02em;
  color: var(--white);
}

.page-faq .faq-block__head .lede {
  max-width: 44ch;
  color: var(--mist);
  line-height: 1.85;
}

.page-faq .faq-block__tail {
  margin: 1.3rem 0 0;
  padding: .85rem 1rem;
  border: 1px dashed var(--line-strong);
  font-size: .9rem;
  line-height: 1.8;
  color: var(--mist);
}

/* ---------- 三级分类 ---------- */
.page-faq .faq-tiers {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: .9rem;
}

.page-faq .faq-tier {
  position: relative;
  background: rgba(14, 42, 78, .5);
  border: 1px solid var(--line-soft);
  border-top: 2px solid var(--line-strong);
  padding: 1.2rem 1.05rem 1.3rem;
}

.page-faq .faq-tier:nth-child(1) {
  border-top-color: var(--cyan);
}

.page-faq .faq-tier:nth-child(2) {
  border-top-color: var(--coral);
}

.page-faq .faq-tier:nth-child(3) {
  border-top-color: var(--violet);
}

.page-faq .faq-tier__k {
  display: inline-block;
  margin: 0 0 .6rem;
}

.page-faq .faq-tier__title {
  margin: 0 0 .5rem;
  font-size: 1.05rem;
  color: var(--white);
  letter-spacing: -0.01em;
}

.page-faq .faq-tier .prose {
  color: var(--mist);
  font-size: .89rem;
  line-height: 1.8;
}

/* ---------- 同步区 ---------- */
.page-faq .faq-sync__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1.2rem, 3.5vw, 2.2rem);
  align-items: start;
}

.page-faq .faq-sync__figure {
  margin: 0;
  border: 2px solid var(--line);
  background: rgba(4, 16, 31, .7);
}

.page-faq .faq-sync__figure .media-frame__img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
}

.page-faq .faq-sync__figure .media-frame__cap {
  padding: .6rem .8rem;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .06em;
  color: var(--mist);
  border-top: 1px solid var(--line-soft);
}

.page-faq .faq-sync__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1rem;
}

.page-faq .faq-sync__list li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: .85rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--line-soft);
}

.page-faq .faq-sync__list li:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.page-faq .faq-sync__n {
  font-family: var(--font-mono);
  font-size: .9rem;
  font-weight: 700;
  letter-spacing: .04em;
  color: var(--cyan);
  line-height: 1.7;
}

.page-faq .faq-sync__list h3 {
  margin: 0 0 .3rem;
  font-size: 1rem;
  color: var(--white);
}

.page-faq .faq-sync__list .prose {
  color: var(--mist);
  font-size: .89rem;
  line-height: 1.8;
}

.page-faq .faq-sync__acts {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .75rem;
  margin-top: 1.3rem;
}

/* ---------- 折叠问答 ---------- */
.page-faq .faq-qa {
  display: grid;
  gap: .6rem;
}

.page-faq .faq-qa__item {
  border: 1px solid var(--line);
  border-left: 3px solid var(--violet);
  background: rgba(14, 42, 78, .45);
  transition: border-color .25s var(--ease), background .25s var(--ease);
}

.page-faq .faq-qa__item[open] {
  background: rgba(14, 42, 78, .78);
  border-color: var(--line-strong);
  border-left-color: var(--cyan);
}

.page-faq .faq-qa__item summary {
  position: relative;
  cursor: pointer;
  list-style: none;
  padding: 1rem 3rem 1rem 1.1rem;
  font-size: .98rem;
  font-weight: 600;
  line-height: 1.6;
  color: var(--white);
  transition: color .25s var(--ease);
}

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

.page-faq .faq-qa__item summary::after {
  content: "+";
  position: absolute;
  right: 1.1rem;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-mono);
  font-size: 1.35rem;
  line-height: 1;
  color: var(--cyan);
  transition: transform .3s var(--ease);
}

.page-faq .faq-qa__item[open] summary::after {
  content: "−";
  transform: translateY(-50%) rotate(180deg);
}

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

.page-faq .faq-qa__panel {
  padding: 0 1.1rem 1.15rem;
  border-top: 1px solid var(--line-soft);
  margin-top: -.1rem;
  padding-top: .9rem;
}

.page-faq .faq-qa__panel .prose {
  margin: 0 0 .7rem;
  color: var(--mist);
  font-size: .9rem;
  line-height: 1.85;
}

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

/* ---------- 反馈帮助 ---------- */
.page-faq .faq-help {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1.2rem, 3.5vw, 2rem);
  align-items: start;
}

.page-faq .faq-help__title {
  margin: 0 0 .8rem;
  font-size: 1.1rem;
  color: var(--white);
  letter-spacing: -0.01em;
}

.page-faq .faq-help__list {
  list-style: none;
  margin: 0 0 1rem;
  padding: 0;
  display: grid;
  gap: .6rem;
}

.page-faq .faq-help__list li {
  position: relative;
  padding-left: 1.15rem;
  font-size: .92rem;
  line-height: 1.8;
  color: var(--mist);
}

.page-faq .faq-help__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .75em;
  width: .5rem;
  height: 2px;
  background: var(--coral);
}

.page-faq .faq-help__list strong {
  color: var(--white);
  font-weight: 600;
}

.page-faq .faq-help__main .prose {
  color: var(--mist);
  font-size: .9rem;
  line-height: 1.85;
}

.page-faq .faq-help__figure {
  margin: 0;
  border: 2px solid var(--line);
  background: rgba(4, 16, 31, .7);
}

.page-faq .faq-help__figure .media-frame__img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
}

.page-faq .faq-help__figure .media-frame__cap {
  padding: .6rem .8rem;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .06em;
  color: var(--mist);
  border-top: 1px solid var(--line-soft);
}

.page-faq .faq-help__contact {
  margin-top: clamp(1.4rem, 3.5vw, 2rem);
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: .7rem;
  border: 1px solid var(--line-soft);
  border-left: 3px solid var(--coral);
  background: rgba(4, 16, 31, .55);
  padding: 1.1rem;
}

.page-faq .faq-help__contact .contact-item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: .15rem;
}

.page-faq .faq-help__contact .contact-item__k {
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .14em;
  color: var(--mist);
}

.page-faq .faq-help__contact .contact-item__v {
  font-size: .92rem;
  line-height: 1.7;
  color: var(--white);
  word-break: break-word;
}

.page-faq .faq-help__note {
  margin: .85rem 0 0;
  font-size: .8rem;
  line-height: 1.75;
  color: var(--mist);
}

/* ---------- 下一步 ---------- */
.page-faq .faq-next {
  margin-top: clamp(2.6rem, 7vw, 4.5rem);
  position: relative;
  border: 2px solid var(--line-strong);
  background: var(--deep);
  clip-path: polygon(0 22px, 22px 0, 100% 0, 100% 100%, 0 100%);
  padding: clamp(1.4rem, 4vw, 2.3rem);
}

.page-faq .faq-next::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;
  height: 4px;
  background: var(--band-b);
}

.page-faq .faq-next__inner h2 {
  margin: .3rem 0 .7rem;
  font-size: clamp(1.35rem, 3.4vw, 2.05rem);
  letter-spacing: -0.02em;
  color: var(--white);
}

.page-faq .faq-next__inner .prose {
  max-width: 48ch;
  color: var(--mist);
  line-height: 1.85;
}

.page-faq .faq-next__acts {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .75rem;
  margin-top: clamp(1.1rem, 3vw, 1.6rem);
}

.page-faq .faq-next__hint {
  margin: .95rem 0 0;
  font-family: var(--font-mono);
  font-size: .75rem;
  letter-spacing: .05em;
  color: var(--mist);
}

/* ---------- 底部悬浮条 ---------- */
.page-faq .sticky-cta {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 40;
  display: flex;
  gap: .6rem;
  padding: .7rem clamp(1rem, 4vw, 2rem);
  background: rgba(4, 16, 31, .94);
  border-top: 1px solid var(--line);
}

.page-faq .sticky-cta .btn {
  flex: 1 1 0;
  text-align: center;
  justify-content: center;
}

/* ---------- 桌面布局 ---------- */
@media (min-width: 62rem) {
  .page-faq .faq-walk__grid {
    grid-template-columns: var(--faq-rail-w) minmax(0, 1fr);
  }

  .page-faq .faq-rail {
    position: sticky;
    top: calc(var(--sticky-top) + 1.6rem);
    align-self: start;
  }

  .page-faq .faq-rail__list {
    flex-direction: column;
    flex-wrap: nowrap;
  }

  .page-faq .faq-rail__link {
    width: 100%;
  }

  .page-faq .faq-tiers {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1rem;
  }

  .page-faq .faq-sync__grid {
    grid-template-columns: minmax(0, 1fr) 1.1fr;
  }

  .page-faq .faq-sync__figure {
    position: sticky;
    top: calc(var(--sticky-top) + 1.6rem);
  }

  .page-faq .faq-help {
    grid-template-columns: 1.15fr minmax(0, 1fr);
  }

  .page-faq .faq-help__contact {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-faq .sticky-cta {
    left: 50%;
    right: auto;
    transform: translateX(-50%);
    bottom: 1.2rem;
    width: min(34rem, calc(100% - 3rem));
    border: 1px solid var(--line-strong);
    border-radius: var(--faq-radius);
    padding: .55rem .7rem;
  }

  .page-faq .sticky-cta .btn {
    flex: 0 0 auto;
  }
}

@media (min-width: 86rem) {
  .page-faq {
    --faq-rail-w: 17rem;
  }
}

/* ---------- 动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-faq .faq-step,
  .page-faq .faq-qa__item,
  .page-faq .faq-qa__item summary::after,
  .page-faq .faq-rail__link,
  .page-faq .crumbs a {
    transition-duration: .12s;
    transition-property: opacity, color, border-color, background;
    transform: none;
  }
}
</main>