.page-faq {
  --faq-sticky: 7.5rem;
  --faq-tick: repeating-linear-gradient(90deg, var(--line) 0 1px, transparent 1px 14px);
  padding-bottom: clamp(3rem, 8vw, 6rem);
}

.page-faq .faq-hero {
  position: relative;
  margin-top: 1.5rem;
  padding: clamp(1.5rem, 5vw, 3.5rem);
  border: 2px solid var(--line);
  background:
    linear-gradient(148deg, rgba(53, 230, 208, 0.13), rgba(154, 107, 255, 0.09) 52%, rgba(7, 12, 28, 0) 88%),
    var(--panel);
  box-shadow: var(--hard-shadow);
  overflow: hidden;
}

.page-faq .faq-hero::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: 5px;
  background: linear-gradient(180deg, var(--cyan), var(--violet));
}

.page-faq .faq-hero::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 12px;
  background-image: var(--faq-tick);
  opacity: 0.65;
}

.page-faq .faq-hero h1 {
  margin: 0.7rem 0 1.1rem;
  max-width: 24ch;
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(1.9rem, 5.6vw, 4rem);
  line-height: 1.03;
  letter-spacing: -0.015em;
  color: var(--text);
}

.page-faq .faq-hero__lede {
  max-width: 64ch;
  margin: 0 0 1.9rem;
  font-family: var(--font-mono);
  font-size: 0.95rem;
  line-height: 1.85;
  color: var(--muted);
}

.page-faq .faq-hero__stats {
  display: flex;
  flex-wrap: wrap;
  gap: 1.1rem 2.4rem;
  padding-top: 1.3rem;
  border-top: 1px solid var(--line);
}

.page-faq .faq-hero__stats .stat {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.page-faq .faq-hero__stats .stat__num {
  font-family: var(--font-mono);
  font-size: 1.55rem;
  font-weight: 500;
  line-height: 1;
}

.page-faq .faq-hero__stats .stat__unit {
  font-family: var(--font-mono);
  font-size: 1.55rem;
  color: var(--cyan);
}

.page-faq .faq-hero__stats .stat__label {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.04em;
  color: var(--muted);
}

/* ---------- 双栏：索引导轨 + 答案流 ---------- */

.page-faq .faq-layout {
  margin-top: clamp(2rem, 6vw, 3.5rem);
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 2.25rem;
}

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

.page-faq .faq-rail__media {
  margin: 0 0 1.4rem;
  border: 2px solid var(--line);
  background: var(--panel);
  box-shadow: 5px 5px 0 rgba(3, 7, 20, 0.7);
  overflow: hidden;
}

.page-faq .faq-rail__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-faq .faq-rail__title {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-faq .faq-index {
  list-style: none;
  margin: 0.75rem 0 0;
  padding: 0;
}

.page-faq .faq-index .index-item {
  margin: 0;
}

.page-faq .faq-index a {
  display: block;
  padding: 0.55rem 0.75rem 0.55rem 0.9rem;
  border-left: 2px solid var(--line);
  color: var(--muted);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  line-height: 1.5;
  text-decoration: none;
  transition: color 180ms var(--ease), border-color 180ms var(--ease), background 180ms var(--ease);
}

.page-faq .faq-index a:hover,
.page-faq .faq-index a:focus-visible {
  color: var(--cyan);
  border-left-color: var(--cyan);
  background: rgba(53, 230, 208, 0.07);
}

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

/* ---------- 过滤条 ---------- */

.page-faq .filter-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 2.2rem;
  padding-bottom: 1.1rem;
  border-bottom: 2px solid var(--line);
}

.page-faq .filter-status {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.04em;
  color: var(--muted);
}

/* ---------- 问答分组 ---------- */

.page-faq .faq-group {
  scroll-margin-top: var(--faq-sticky);
}

.page-faq .faq-group + .faq-group {
  margin-top: clamp(2.6rem, 6vw, 4.2rem);
}

.page-faq .faq-group__lede {
  max-width: 62ch;
  margin: 0.9rem 0 1.5rem;
  padding-left: 0.9rem;
  border-left: 2px solid var(--violet);
  font-family: var(--font-mono);
  font-size: 0.88rem;
  line-height: 1.85;
  color: var(--muted);
}

/* ---------- 四步检查轨道 ---------- */

.page-faq .faq-media {
  margin: 0 0 1.6rem;
  border: 2px solid var(--line);
  background: var(--panel);
  box-shadow: var(--hard-shadow);
  overflow: hidden;
}

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

.page-faq .faq-media figcaption {
  padding: 0.7rem 1rem;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.04em;
  color: var(--muted);
}

.page-faq .faq-steps {
  display: flex;
  gap: 0.9rem;
  list-style: none;
  margin: 0 0 1.8rem;
  padding: 0 0 0.9rem;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  -webkit-overflow-scrolling: touch;
}

.page-faq .faq-step {
  flex: 0 0 78%;
  scroll-snap-align: start;
  padding: 1rem 1.05rem 1.1rem;
  border: 2px solid var(--line);
  background:
    linear-gradient(158deg, rgba(154, 107, 255, 0.13), rgba(7, 12, 28, 0) 72%),
    var(--panel);
}

.page-faq .faq-step__no {
  display: inline-grid;
  place-items: center;
  width: 26px;
  height: 26px;
  margin-bottom: 0.65rem;
  border: 2px solid var(--cyan);
  color: var(--cyan);
  font-family: var(--font-mono);
  font-size: 0.76rem;
  line-height: 1;
}

.page-faq .faq-step__title {
  display: block;
  margin-bottom: 0.4rem;
  font-family: var(--font-mono);
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text);
}

.page-faq .faq-step__desc {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 问答折叠项 ---------- */

.page-faq .faq-item {
  border: 2px solid var(--line);
  background: var(--panel);
  box-shadow: 5px 5px 0 rgba(3, 7, 20, 0.7);
  transition: border-color 200ms var(--ease), box-shadow 200ms var(--ease);
}

.page-faq .faq-item + .faq-item {
  margin-top: 0.85rem;
}

.page-faq .faq-item[open] {
  border-color: rgba(53, 230, 208, 0.5);
}

.page-faq .faq-item > summary {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  padding: 1rem 1.1rem;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 0.88rem;
  line-height: 1.65;
  color: var(--text);
  transition: color 180ms var(--ease);
}

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

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

.page-faq .faq-item > summary::after {
  content: "+";
  flex: none;
  margin-left: auto;
  color: var(--cyan);
  font-size: 1.1rem;
  line-height: 1;
}

.page-faq .faq-item[open] > summary::after {
  content: "–";
}

.page-faq .faq-item__no {
  flex: none;
  padding-top: 0.1rem;
  font-size: 0.74rem;
  letter-spacing: 0.08em;
  color: var(--cyan);
}

.page-faq .faq-group--rule .faq-item__no {
  color: var(--amber);
}

.page-faq .faq-group--rule .faq-item[open] {
  border-color: rgba(255, 180, 58, 0.5);
}

.page-faq .faq-item__a {
  padding: 0 1.1rem 1.15rem 1.1rem;
  font-family: var(--font-mono);
  font-size: 0.86rem;
  line-height: 1.9;
  color: var(--muted);
}

.page-faq .faq-item__a p {
  margin: 0 0 0.7rem;
}

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

.page-faq .faq-item__a a {
  color: var(--cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- 自助排查清单 ---------- */

.page-faq .faq-checklist {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 2px solid var(--line);
}

.page-faq .faq-check {
  display: flex;
  align-items: flex-start;
  gap: 0.9rem;
  padding: 0.95rem 0.2rem;
  border-bottom: 1px dashed var(--line);
  font-family: var(--font-mono);
  font-size: 0.86rem;
  line-height: 1.75;
  color: var(--text);
}

.page-faq .faq-check__box {
  flex: none;
  display: grid;
  place-items: center;
  width: 22px;
  height: 22px;
  margin-top: 0.15rem;
  border: 2px solid var(--cyan);
  color: var(--cyan);
  font-size: 0.78rem;
  line-height: 1;
}

.page-faq .faq-check__box::after {
  content: "✓";
}

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

.page-faq .faq-check__tail {
  margin: 1.4rem 0 0;
  padding-left: 0.9rem;
  border-left: 2px solid var(--amber);
  font-family: var(--font-mono);
  font-size: 0.84rem;
  line-height: 1.85;
  color: var(--muted);
}

.page-faq .faq-check__tail a {
  color: var(--cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- 末端指引条 ---------- */

.page-faq .faq-continue {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-top: clamp(2.4rem, 6vw, 3.6rem);
  padding: 1.2rem 1.3rem;
}

.page-faq .faq-continue__text {
  margin: 0;
  max-width: 54ch;
  font-family: var(--font-mono);
  font-size: 0.86rem;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 响应式 ---------- */

@media (min-width: 640px) {
  .page-faq .faq-step {
    flex: 0 0 44%;
  }

  .page-faq .faq-item > summary {
    font-size: 0.92rem;
    padding: 1.05rem 1.25rem;
  }

  .page-faq .faq-item__a {
    padding: 0 1.25rem 1.25rem 3.2rem;
    font-size: 0.88rem;
  }
}

@media (min-width: 900px) {
  .page-faq .faq-step {
    flex: 0 0 230px;
  }
}

@media (min-width: 1024px) {
  .page-faq .faq-layout {
    grid-template-columns: 300px minmax(0, 1fr);
    gap: 3.5rem;
    align-items: start;
  }

  .page-faq .faq-rail {
    position: sticky;
    top: var(--faq-sticky);
  }
}

@media (min-width: 1200px) {
  .page-faq .faq-step {
    flex: 1 1 0;
  }
}

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