/* ===== 页面：使用问答 /questions/ ===== */
.page-faq {
  --faq-step-offset: 54px;
}

.page-faq .faq-masthead {
  max-width: 62ch;
  padding-block: clamp(24px, 4vw, 46px) clamp(10px, 2vw, 18px);
}

.page-faq .faq-masthead h1 {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-size: clamp(31px, 5.6vw, 58px);
  font-weight: 800;
  line-height: 1.02;
  letter-spacing: -0.01em;
  color: var(--chalk);
}

.page-faq .faq-lede {
  margin: 16px 0 0;
  max-width: 38em;
  font-size: 16px;
  line-height: 1.75;
  color: var(--mist);
}

.page-faq .faq-powerline {
  display: flex;
  flex-wrap: wrap;
  gap: 14px clamp(20px, 4vw, 44px);
  margin: 26px 0 0;
  padding: 18px 0 0;
  border-top: 1px solid var(--line);
  list-style: none;
}

.page-faq .faq-powerline li {
  display: flex;
  align-items: baseline;
  gap: 8px;
}

.page-faq .faq-powerline .mono {
  font-size: clamp(20px, 3vw, 26px);
  font-variant-numeric: tabular-nums lining-nums;
  color: var(--teal);
}

.page-faq .faq-powerline li span:last-child {
  font-size: 13px;
  letter-spacing: 0.02em;
  color: var(--mute);
}

/* 主体：左索引 + 右问答流 */
.page-faq .faq-shell {
  margin-top: clamp(28px, 4vw, 48px);
}

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

.page-faq .faq-index {
  margin-bottom: clamp(24px, 4vw, 36px);
  padding: 16px 14px 18px;
  border: 1px solid var(--line);
  background: var(--ink-2);
}

.page-faq .faq-index-title {
  margin: 0 0 10px;
  padding-left: 10px;
  font-family: var(--font-display);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.22em;
  color: var(--mute);
}

.page-faq .faq-index-list {
  display: grid;
  gap: 2px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-faq .faq-index-list a {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 9px 10px;
  border-left: 2px solid var(--line);
  font-size: 15px;
  color: var(--mist);
  text-decoration: none;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease),
    background-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-faq .faq-index-list a .mono {
  font-size: 12px;
  color: var(--mute);
  transition: color var(--dur) var(--ease);
}

.page-faq .faq-index-list a:hover,
.page-faq .faq-index-list a:focus-visible {
  color: var(--chalk);
  border-left-color: var(--teal);
  background: rgba(53, 224, 190, 0.08);
  transform: translateX(3px);
}

.page-faq .faq-index-list a:hover .mono,
.page-faq .faq-index-list a:focus-visible .mono {
  color: var(--teal);
}

.page-faq .faq-index-list a:focus-visible {
  outline: 2px solid var(--teal);
  outline-offset: 2px;
}

.page-faq .faq-index-note {
  margin: 14px 0 0;
  padding-left: 10px;
  font-size: 12px;
  line-height: 1.65;
  color: var(--mute);
}

.page-faq .faq-index-cta {
  margin: 14px 0 0 10px;
}

/* 分组 */
.page-faq .faq-group {
  scroll-margin-top: calc(var(--bar-h) + 24px);
}

.page-faq .faq-group + .faq-group {
  margin-top: clamp(42px, 6vw, 74px);
}

.page-faq .faq-group-head {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line);
}

.page-faq .faq-group-num {
  flex: none;
  font-size: clamp(30px, 4.6vw, 42px);
  line-height: 0.9;
  font-variant-numeric: tabular-nums lining-nums;
  color: var(--teal);
  opacity: 0.85;
}

.page-faq .faq-group-titles {
  min-width: 0;
}

.page-faq .faq-group-titles h2 {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(21px, 3vw, 28px);
  font-weight: 700;
  line-height: 1.15;
  color: var(--chalk);
}

.page-faq .faq-group-sub {
  margin: 6px 0 0;
  font-size: 14px;
  line-height: 1.65;
  color: var(--mute);
}

.page-faq .faq-figure {
  margin: 20px 0 4px;
}

.page-faq .faq-figure figcaption {
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--mute);
}

/* 问答条目 */
.page-faq .faq-list {
  display: grid;
  gap: 10px;
  margin-top: 18px;
}

.page-faq .faq-item {
  border: 1px solid var(--line);
  border-left: 3px solid var(--line);
  background: var(--board);
  transition: border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease),
    background-color var(--dur) var(--ease);
}

.page-faq .faq-item:hover {
  border-left-color: var(--mist);
}

.page-faq .faq-item[open] {
  border-left-color: var(--teal);
  background-image: linear-gradient(0deg, rgba(53, 224, 190, 0.05), rgba(53, 224, 190, 0.05));
  box-shadow: 5px 5px 0 rgba(8, 19, 15, 0.55);
}

.page-faq .faq-q {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 15px 16px;
  cursor: pointer;
  list-style: none;
}

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

.page-faq .faq-q::marker {
  content: "";
}

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

.page-faq .faq-q-mark {
  flex: none;
  padding-top: 3px;
  font-size: 12px;
  font-variant-numeric: tabular-nums;
  color: var(--mute);
  transition: color var(--dur) var(--ease);
}

.page-faq .faq-item[open] .faq-q-mark {
  color: var(--teal);
}

.page-faq .faq-q-text {
  min-width: 0;
  font-family: var(--font-body);
  font-size: clamp(16px, 2.1vw, 18px);
  font-weight: 600;
  line-height: 1.5;
  letter-spacing: 0.01em;
  color: var(--chalk);
  overflow-wrap: break-word;
}

.page-faq .faq-chev {
  flex: none;
  align-self: center;
  margin-left: auto;
  width: 9px;
  height: 9px;
  border-right: 2px solid var(--mute);
  border-bottom: 2px solid var(--mute);
  transform: rotate(45deg);
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-faq .faq-item[open] .faq-chev {
  transform: rotate(-135deg);
  border-color: var(--teal);
}

.page-faq .faq-a {
  padding: 0 28px 18px 16px;
}

.page-faq .faq-a > * {
  transition: transform var(--dur-slow) var(--ease);
}

.page-faq .faq-item[open] .faq-a > * {
  transform: translateX(8px);
}

.page-faq .faq-a p {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--chalk);
}

.page-faq .faq-a p + p {
  margin-top: 12px;
}

.page-faq .faq-a a {
  color: var(--teal);
  text-decoration-color: rgba(53, 224, 190, 0.4);
  text-underline-offset: 3px;
}

.page-faq .faq-a a:hover,
.page-faq .faq-a a:focus-visible {
  text-decoration-color: var(--teal);
}

.page-faq .faq-note {
  border-left: 3px solid var(--flare);
  padding: 2px 0 2px 14px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--mist);
}

/* 步骤 */
.page-faq .faq-steps {
  display: grid;
  gap: 12px;
  margin: 6px 0 0;
  padding: 0;
  list-style: none;
  counter-reset: faqstep;
}

.page-faq .faq-steps > li {
  position: relative;
  min-height: 32px;
  padding-left: var(--faq-step-offset);
  font-size: 15px;
  line-height: 1.7;
  color: var(--chalk);
  overflow-wrap: break-word;
  counter-increment: faqstep;
}

.page-faq .faq-steps > li::before {
  content: counter(faqstep, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: -3px;
  font-family: var(--font-num);
  font-size: 26px;
  font-weight: 500;
  line-height: 1;
  letter-spacing: -0.02em;
  font-variant-numeric: tabular-nums lining-nums;
  color: var(--teal);
}

.page-faq .faq-steps > li + li::after {
  content: "";
  position: absolute;
  left: 14px;
  top: -12px;
  width: 1px;
  height: 9px;
  background: var(--line);
}

/* 收尾 */
.page-faq .faq-outro {
  margin-top: clamp(48px, 7vw, 82px);
  padding: clamp(20px, 3vw, 30px);
  border: 1px solid var(--line);
  border-top: 3px solid var(--flare);
  background: var(--ink-2);
}

.page-faq .faq-outro h2 {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(20px, 2.6vw, 26px);
  font-weight: 700;
  color: var(--chalk);
}

.page-faq .faq-outro p {
  margin: 10px 0 0;
  max-width: 46ch;
  font-size: 15px;
  line-height: 1.7;
  color: var(--mist);
}

.page-faq .faq-outro-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 18px;
}

/* 桌面：左索引常驻 */
@media (min-width: 940px) {
  .page-faq .faq-shell {
    display: grid;
    grid-template-columns: minmax(180px, 224px) minmax(0, 1fr);
    gap: clamp(28px, 4vw, 60px);
    align-items: start;
  }

  .page-faq .faq-index {
    position: sticky;
    top: calc(var(--bar-h) + 28px);
    margin-bottom: 0;
  }
}

@media (max-width: 520px) {
  .page-faq {
    --faq-step-offset: 44px;
  }

  .page-faq .faq-steps > li::before {
    font-size: 22px;
  }

  .page-faq .faq-steps > li + li::after {
    left: 11px;
  }

  .page-faq .faq-q {
    gap: 10px;
    padding: 14px 13px;
  }

  .page-faq .faq-a {
    padding: 0 18px 16px 13px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-faq .faq-item,
  .page-faq .faq-chev,
  .page-faq .faq-a > *,
  .page-faq .faq-index-list a,
  .page-faq .faq-q-mark {
    transition: none;
  }

  .page-faq .faq-item[open] .faq-a > *,
  .page-faq .faq-index-list a:hover,
  .page-faq .faq-index-list a:focus-visible {
    transform: none;
  }
}