.page-faq {
  --faq-rail-w: 320px;
  --faq-tab: 12px;
  color: var(--ice);
  display: block;
  overflow-x: hidden;
}

.page-faq .mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

/* ---------- 首屏拼贴 ---------- */
.page-faq .faq-hero {
  position: relative;
  padding: calc(var(--header-h) + 34px) 0 30px;
  background:
    radial-gradient(120% 80% at 88% 0%, rgba(225, 6, 0, .22) 0%, rgba(18, 18, 18, 0) 62%),
    var(--carbon);
  overflow: hidden;
}

.page-faq .faq-hero::before {
  content: "";
  position: absolute;
  inset: -10% -5%;
  background-image: repeating-linear-gradient(112deg, rgba(244, 246, 248, .055) 0 1px, transparent 1px 24px);
  pointer-events: none;
}

.page-faq .faq-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--red) 0%, var(--red-dark) 46%, transparent 100%);
}

.page-faq .faq-hero__inner {
  position: relative;
  display: grid;
  gap: 26px;
}

.page-faq .faq-hero h1 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(32px, 8.2vw, 66px);
  line-height: 1.03;
  letter-spacing: -.02em;
  color: var(--ice);
  margin: 12px 0 16px;
  max-width: 15em;
}

.page-faq .faq-hero__text {
  font-size: 16px;
  line-height: 1.8;
  color: var(--fog);
  margin: 0;
  max-width: 46ch;
}

.page-faq .faq-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 22px;
}

.page-faq .faq-hero__board {
  position: relative;
  background: var(--carbon-2);
  border: 1px solid var(--line-strong);
  box-shadow: var(--shadow-panel);
  padding: 22px 20px 24px;
  display: grid;
  gap: 14px;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 18px), calc(100% - 18px) 100%, 0 100%);
}

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

.page-faq .faq-hero__board .tag {
  justify-self: start;
}

.page-faq .faq-hero__stat {
  display: flex;
  align-items: baseline;
  gap: 12px;
  flex-wrap: wrap;
  padding-bottom: 12px;
  border-bottom: 1px dashed var(--line);
}

.page-faq .faq-hero__stat:last-of-type {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-faq .faq-hero__num {
  font-family: var(--font-mono);
  font-size: clamp(26px, 7vw, 32px);
  font-weight: 600;
  line-height: 1;
  color: var(--lime);
  font-variant-numeric: tabular-nums;
}

.page-faq .faq-hero__cap {
  font-size: 13px;
  line-height: 1.55;
  color: var(--fog);
}

.page-faq .faq-hero__board .note-vertical {
  position: absolute;
  right: 8px;
  top: 20px;
  writing-mode: vertical-rl;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .36em;
  color: var(--red);
  pointer-events: none;
}

/* ---------- 主体骨架 ---------- */
.page-faq .faq-body {
  display: grid;
  gap: 26px;
  padding-top: 34px;
  padding-bottom: 60px;
}

/* ---------- 左侧索引栏 ---------- */
.page-faq .faq-rail {
  display: grid;
  gap: 16px;
  min-width: 0;
}

.page-faq .faq-rail__figure {
  margin: 0;
  border: 1px solid var(--line-strong);
  background: var(--carbon-2);
  overflow: hidden;
}

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

.page-faq .faq-rail__nav {
  display: grid;
  gap: 8px;
}

.page-faq .faq-rail__card {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: 4px 10px;
  padding: 12px 14px;
  background: var(--paper);
  color: var(--carbon);
  text-decoration: none;
  border: 1px solid var(--carbon);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 10px), calc(100% - 10px) 100%, 0 100%);
  transition: transform .22s var(--ease), box-shadow .22s var(--ease);
}

.page-faq .faq-rail__card:hover {
  transform: translateY(-3px);
  box-shadow: 6px 6px 0 var(--red);
}

.page-faq .faq-rail__card:focus-visible {
  outline: 2px solid var(--blue);
  outline-offset: 3px;
}

.page-faq .faq-rail__num {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  color: var(--red);
  letter-spacing: .08em;
}

.page-faq .faq-rail__name {
  font-size: 15px;
  font-weight: 700;
  line-height: 1.35;
}

.page-faq .faq-rail__count {
  font-family: var(--font-mono);
  font-size: 11px;
  color: rgba(18, 18, 18, .5);
  border: 1px solid rgba(18, 18, 18, .28);
  padding: 1px 6px;
}

.page-faq .faq-rail__picks {
  grid-column: 1 / -1;
  font-size: 12px;
  line-height: 1.6;
  color: rgba(18, 18, 18, .62);
  border-top: 1px dashed rgba(18, 18, 18, .22);
  padding-top: 6px;
}

.page-faq .faq-rail__side {
  border: 1px solid var(--line);
  background: var(--carbon-2);
  padding: 16px 16px 18px;
}

.page-faq .faq-rail__side-title {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .2em;
  color: var(--lime);
}

.page-faq .faq-rail__side p {
  margin: 0 0 8px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--fog);
}

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

.page-faq .faq-rail__side a {
  color: var(--blue);
  text-decoration: none;
  border-bottom: 1px solid rgba(0, 163, 255, .4);
}

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

/* ---------- 问答分组 ---------- */
.page-faq .faq-groups {
  display: grid;
  gap: 26px;
  min-width: 0;
}

.page-faq .faq-group {
  position: relative;
  background: var(--carbon-2);
  border: 1px solid var(--line-strong);
  border-left: 4px solid var(--red);
  box-shadow: var(--shadow-panel);
  padding: 22px 16px 20px;
  min-width: 0;
  scroll-margin-top: calc(var(--header-h) + 24px);
  animation: faq-panel-rise .5s var(--ease) both;
}

.page-faq .faq-group:nth-of-type(2) { animation-delay: .06s; }
.page-faq .faq-group:nth-of-type(3) { animation-delay: .12s; }
.page-faq .faq-group:nth-of-type(4) { animation-delay: .18s; }
.page-faq .faq-group:nth-of-type(5) { animation-delay: .24s; }
.page-faq .faq-group:nth-of-type(6) { animation-delay: .3s; }

@keyframes faq-panel-rise {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: translateY(0); }
}

.page-faq .faq-group__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--red);
}

.page-faq .faq-group__title {
  margin: 8px 0 10px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(22px, 5.4vw, 30px);
  line-height: 1.22;
  color: var(--ice);
}

.page-faq .faq-group__lead {
  margin: 0 0 18px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--fog);
  max-width: 58ch;
}

.page-faq .faq-group__foot {
  margin: 16px 0 0;
  padding-top: 14px;
  border-top: 1px dashed var(--line);
  font-size: 13px;
  line-height: 1.7;
  color: var(--fog);
}

.page-faq .faq-group__foot a {
  color: var(--blue);
  text-decoration: none;
  border-bottom: 1px solid rgba(0, 163, 255, .4);
}

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

/* ---------- 配图与示意图 ---------- */
.page-faq .faq-figure {
  margin: 0 0 18px;
  border: 1px solid var(--line-strong);
  background: var(--carbon);
}

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

.page-faq .faq-figure figcaption {
  padding: 10px 12px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--fog);
  border-top: 1px solid var(--line);
}

.page-faq .faq-diagram {
  margin: 0 0 18px;
  border: 1px solid var(--line-strong);
  background: var(--carbon);
  padding: 14px 14px 10px;
}

.page-faq .faq-diagram svg {
  display: block;
  width: 100%;
  height: auto;
}

/* ---------- 折叠问答 ---------- */
.page-faq .faq-q {
  border-top: 1px solid var(--line);
}

.page-faq .faq-q:last-child {
  border-bottom: 1px solid var(--line);
}

.page-faq .faq-q__trigger {
  width: 100%;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: start;
  gap: 12px;
  padding: 15px 2px;
  background: none;
  border: 0;
  color: var(--ice);
  font-family: var(--font-body);
  font-size: 16px;
  font-weight: 700;
  line-height: 1.55;
  text-align: left;
  cursor: pointer;
  transition: color .2s var(--ease);
}

.page-faq .faq-q__trigger:hover {
  color: var(--blue);
}

.page-faq .faq-q__trigger:focus-visible {
  outline: 2px solid var(--blue);
  outline-offset: 2px;
  color: var(--blue);
}

.page-faq .faq-q__id {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  color: var(--fog);
  padding-top: 4px;
  font-variant-numeric: tabular-nums;
}

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

.page-faq .faq-q__mark {
  position: relative;
  width: 20px;
  height: 20px;
  margin-top: 3px;
  border: 1px solid var(--line-strong);
  flex: none;
}

.page-faq .faq-q__mark::before,
.page-faq .faq-q__mark::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  background: var(--lime);
  transform: translate(-50%, -50%);
  transition: transform .24s var(--ease), opacity .24s var(--ease);
}

.page-faq .faq-q__mark::before {
  width: 10px;
  height: 2px;
}

.page-faq .faq-q__mark::after {
  width: 2px;
  height: 10px;
}

.page-faq [data-accordion-item][data-open="true"] .faq-q__mark::after {
  transform: translate(-50%, -50%) scaleY(0);
  opacity: 0;
}

.page-faq [data-accordion-item][data-open="true"] .faq-q__trigger {
  color: var(--ice);
}

.page-faq .faq-q__panel {
  padding-left: 30px;
}

.page-faq [data-accordion-item][data-open="false"] > .faq-q__panel {
  display: none;
}

.page-faq .faq-a {
  border-left: 2px solid var(--red);
  padding: 2px 0 18px 14px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--fog);
  animation: faq-answer-in .3s var(--ease) both;
}

@keyframes faq-answer-in {
  from { opacity: 0; transform: translateY(-4px); }
  to { opacity: 1; transform: translateY(0); }
}

.page-faq .faq-a p {
  margin: 0 0 8px;
}

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

.page-faq .faq-steps {
  counter-reset: faq-step;
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 9px;
}

.page-faq .faq-steps li {
  position: relative;
  padding-left: 36px;
}

.page-faq .faq-steps li::before {
  counter-increment: faq-step;
  content: counter(faq-step, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 2px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  color: var(--lime);
  border: 1px solid var(--line-strong);
  padding: 0 5px;
  line-height: 1.6;
}

/* ---------- 联系收束 ---------- */
.page-faq .faq-contact {
  position: relative;
  margin-top: 6px;
  background: linear-gradient(135deg, var(--red) 0%, var(--red-dark) 96%);
  border: 1px solid var(--red);
  padding: 26px 20px 28px;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 20px), calc(100% - 20px) 100%, 0 100%);
}

.page-faq .faq-contact .eyebrow {
  color: rgba(244, 246, 248, .72);
}

.page-faq .faq-contact h2 {
  margin: 10px 0 12px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(21px, 5vw, 28px);
  line-height: 1.25;
  color: var(--ice);
  max-width: 24em;
}

.page-faq .faq-contact__lead {
  margin: 0 0 18px;
  font-size: 15px;
  line-height: 1.75;
  color: rgba(244, 246, 248, .88);
  max-width: 52ch;
}

.page-faq .faq-contact__list {
  margin: 0;
  display: grid;
  gap: 10px;
  border-top: 1px solid rgba(244, 246, 248, .28);
  padding-top: 16px;
}

.page-faq .faq-contact__list > div {
  display: grid;
  gap: 2px;
}

.page-faq .faq-contact__list dt {
  font-size: 12px;
  letter-spacing: .12em;
  color: rgba(244, 246, 248, .72);
}

.page-faq .faq-contact__list dd {
  margin: 0;
  font-size: 15px;
  font-weight: 700;
  color: var(--ice);
  word-break: break-word;
}

.page-faq .faq-contact .btn {
  display: inline-flex;
  align-items: center;
  margin-top: 20px;
  background: transparent;
  border-color: var(--ice);
  color: var(--ice);
}

.page-faq .faq-contact .btn:hover,
.page-faq .faq-contact .btn:focus-visible {
  background: var(--ice);
  border-color: var(--ice);
  color: var(--red-dark);
}

/* ---------- 响应式 ---------- */
@media (min-width: 700px) {
  .page-faq .faq-hero {
    padding-top: calc(var(--header-h) + 56px);
    padding-bottom: 44px;
  }

  .page-faq .faq-hero__inner {
    gap: 34px;
  }

  .page-faq .faq-group {
    padding: 26px 24px 24px;
  }

  .page-faq .faq-q__trigger {
    font-size: 17px;
    padding: 17px 2px;
  }

  .page-faq .faq-contact {
    padding: 32px 28px 34px;
  }

  .page-faq .faq-contact__list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
  }
}

@media (min-width: 960px) {
  .page-faq .faq-hero__inner {
    grid-template-columns: minmax(0, 1.55fr) minmax(0, 1fr);
    align-items: end;
  }

  .page-faq .faq-body {
    grid-template-columns: var(--faq-rail-w) minmax(0, 1fr);
    gap: 38px;
    align-items: start;
    padding-top: 46px;
    padding-bottom: 76px;
  }

  .page-faq .faq-rail {
    position: sticky;
    top: calc(var(--header-h) + 20px);
  }

  .page-faq .faq-groups {
    gap: 32px;
  }

  .page-faq .faq-q__panel {
    padding-left: 44px;
  }
}

@media (min-width: 1200px) {
  .page-faq {
    --faq-rail-w: 336px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-faq *,
  .page-faq *::before,
  .page-faq *::after {
    animation-duration: .001ms !important;
    animation-delay: 0ms !important;
    transition-duration: .001ms !important;
  }
}
</main>