.page-faq {
  --faq-line: rgba(11, 59, 46, 0.16);
  --faq-ink-soft: rgba(16, 24, 21, 0.82);
  --faq-body-max: 62ch;
  background: var(--chrome);
  color: var(--ink);
}

.page-faq__crumbs {
  padding-top: clamp(1.25rem, 3vw, 2rem);
}

/* ---------- 首屏 ---------- */

.page-faq .faq-hero {
  padding-block: clamp(1.5rem, 4vw, 2.5rem) clamp(2.25rem, 5vw, 4rem);
}

.page-faq .faq-hero__grid {
  display: grid;
  gap: clamp(1.75rem, 4vw, 3.25rem);
}

.page-faq .faq-hero__text {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  max-width: 40rem;
}

.page-faq .faq-hero__text .mono-label {
  color: var(--pitch-2);
}

.page-faq .faq-hero h1 {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(2rem, 6.2vw, 3.35rem);
  line-height: 1.08;
  letter-spacing: -0.012em;
  margin: 0;
  color: var(--pitch);
  max-width: 18ch;
}

.page-faq .faq-hero .lede {
  font-size: clamp(1rem, 1.6vw, 1.125rem);
  line-height: 1.85;
  color: var(--faq-ink-soft);
  max-width: 34ch;
  margin: 0;
}

.page-faq .faq-hero__meta {
  list-style: none;
  margin: 0.5rem 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.5rem;
}

.page-faq .faq-hero__meta li {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
  font-size: 0.8125rem;
  letter-spacing: 0.06em;
  color: var(--pitch-2);
}

.page-faq .faq-hero__num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.375rem;
  color: var(--pitch);
  border-bottom: 3px solid var(--signal);
  padding-bottom: 0.1em;
}

.page-faq .faq-hero__mark {
  width: 76px;
  height: 76px;
  color: var(--signal);
  margin-top: 0.75rem;
  flex: none;
}

.page-faq .faq-hero__figure {
  margin: 0;
}

/* ---------- 正文骨架 ---------- */

.page-faq .faq-body {
  padding-bottom: clamp(3rem, 8vw, 6rem);
}

.page-faq .faq-layout {
  display: grid;
  gap: clamp(1.5rem, 4vw, 3.5rem);
}

/* 索引 */

.page-faq .faq-index {
  border-top: 3px solid var(--pitch);
  padding-top: 0.85rem;
}

.page-faq .faq-index__label {
  margin: 0 0 0.7rem;
  color: var(--pitch-2);
}

.page-faq .faq-index__list {
  list-style: none;
  margin: 0;
  padding: 0 0 0.5rem;
  display: flex;
  gap: 0.5rem;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-faq .faq-index__list li {
  flex: none;
}

.page-faq .faq-index__list a {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.45rem 0.85rem;
  font-size: 0.875rem;
  font-weight: 700;
  white-space: nowrap;
  text-decoration: none;
  color: var(--pitch);
  background: var(--chalk);
  border: 2px solid var(--pitch);
  transition: background-color 140ms var(--ease), color 140ms var(--ease);
}

.page-faq .faq-index__list a:hover {
  background: var(--signal);
}

.page-faq .faq-index__no {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 0.75rem;
  color: var(--pitch-2);
}

/* 问题列 */

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

.page-faq .faq-group {
  border-top: 3px solid var(--pitch);
  padding-top: 1.1rem;
  margin-bottom: clamp(2.25rem, 5vw, 3.5rem);
}

.page-faq .faq-group:last-of-type {
  margin-bottom: 0;
}

.page-faq .faq-group__head {
  display: flex;
  align-items: center;
  gap: 0.9rem;
  margin-bottom: 0.5rem;
}

.page-faq .faq-group__num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1rem;
  line-height: 1;
  padding: 0.45em 0.55em;
  background: var(--pitch);
  color: var(--signal);
}

.page-faq .faq-group h2 {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(1.25rem, 2.6vw, 1.6rem);
  letter-spacing: 0.01em;
  margin: 0;
  color: var(--pitch);
}

/* details 条目 */

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

.page-faq .faq-item summary {
  list-style: none;
  cursor: pointer;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: start;
  gap: 1rem;
  padding: 1.05rem 0;
  color: var(--ink);
  transition: color 140ms var(--ease);
}

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

.page-faq .faq-item__q {
  font-weight: 700;
  font-size: 1rem;
  line-height: 1.6;
  background-image: linear-gradient(var(--signal), var(--signal));
  background-repeat: no-repeat;
  background-size: 0% 2px;
  background-position: 0 100%;
  transition: background-size 180ms var(--ease), color 140ms var(--ease);
}

.page-faq .faq-item summary:hover .faq-item__q {
  background-size: 100% 2px;
}

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

.page-faq .faq-item__mark {
  position: relative;
  width: 20px;
  height: 20px;
  margin-top: 0.3rem;
  border: 2px solid var(--pitch);
  flex: none;
  transition: background-color 140ms var(--ease), border-color 140ms var(--ease);
}

.page-faq .faq-item__mark::before,
.page-faq .faq-item__mark::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  background: var(--pitch);
  transform: translate(-50%, -50%);
  transition: transform 160ms var(--ease), opacity 160ms var(--ease);
}

.page-faq .faq-item__mark::before {
  width: 9px;
  height: 2px;
}

.page-faq .faq-item__mark::after {
  width: 2px;
  height: 9px;
}

.page-faq .faq-item[open] > summary .faq-item__mark {
  background: var(--signal);
}

.page-faq .faq-item[open] > summary .faq-item__mark::after {
  transform: translate(-50%, -50%) scaleY(0);
  opacity: 0;
}

.page-faq .faq-item__body {
  max-width: var(--faq-body-max);
  padding: 0 0 1.4rem 1rem;
  border-left: 3px solid var(--signal);
  font-size: 1rem;
  line-height: 1.85;
  color: var(--faq-ink-soft);
}

.page-faq .faq-item__body p {
  margin: 0 0 0.75rem;
}

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

.page-faq .faq-item__body a {
  color: var(--pitch);
  font-weight: 700;
  text-decoration: underline;
  text-decoration-color: var(--signal);
  text-decoration-thickness: 2px;
  text-underline-offset: 3px;
  transition: color 140ms var(--ease);
}

.page-faq .faq-item__body a:hover {
  color: var(--pitch-2);
}

.page-faq .faq-list {
  list-style: none;
  margin: 0.75rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.55rem;
}

.page-faq .faq-list li {
  padding-left: 0.85rem;
  border-left: 3px solid var(--chalk);
  font-size: 0.9375rem;
  line-height: 1.7;
}

.page-faq .faq-list .mono {
  color: var(--pitch);
  font-weight: 700;
}

/* 组内配图 */

.page-faq .faq-inline-figure {
  margin: 1.75rem 0 0;
  max-width: 34rem;
}

/* 焦点可见 */

.page-faq a:focus-visible,
.page-faq summary:focus-visible {
  outline: 3px solid var(--varblue);
  outline-offset: 3px;
}

/* ---------- 桌面栅格 ---------- */

@media (min-width: 900px) {
  .page-faq .faq-hero__grid {
    grid-template-columns: minmax(0, 1.02fr) minmax(0, 0.98fr);
    grid-template-areas: "figure text";
    align-items: end;
    column-gap: clamp(2rem, 5vw, 4rem);
  }

  .page-faq .faq-hero__figure {
    grid-area: figure;
    margin-bottom: 0.5rem;
  }

  .page-faq .faq-hero__text {
    grid-area: text;
    padding-bottom: 0.75rem;
  }

  .page-faq .faq-hero__mark {
    position: absolute;
    right: 0;
    bottom: -0.5rem;
    width: 92px;
    height: 92px;
    opacity: 0.75;
    pointer-events: none;
  }

  .page-faq .faq-hero__text {
    position: relative;
  }
}

@media (min-width: 1000px) {
  .page-faq .faq-layout {
    grid-template-columns: 13.5rem minmax(0, 1fr);
    align-items: start;
  }

  .page-faq .faq-index {
    position: sticky;
    top: 6.5rem;
  }

  .page-faq .faq-index__list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-faq .faq-index__list li + li {
    margin-top: 0.35rem;
  }

  .page-faq .faq-index__list a {
    width: 100%;
    padding: 0.6rem 0.8rem;
    background: transparent;
    border-color: transparent;
    border-left: 3px solid var(--faq-line);
  }

  .page-faq .faq-index__list a:hover {
    background: var(--chalk);
    border-left-color: var(--pitch);
  }
}

@media (min-width: 1200px) {
  .page-faq .faq-hero h1 {
    font-size: 3.6rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-faq .faq-item__q,
  .page-faq .faq-item__mark,
  .page-faq .faq-item__mark::before,
  .page-faq .faq-item__mark::after,
  .page-faq .faq-index__list a {
    transition: none;
  }
}