.page-faq {
  --faq-rail: 14rem;
  --faq-gap: clamp(1.75rem, 4vw, 3.5rem);
  --faq-pad-left: clamp(2.4rem, 5.5vw, 4.2rem);
  display: block;
  width: 100%;
  overflow-x: clip;
  padding-bottom: clamp(3.5rem, 9vw, 7rem);
  interpolate-size: allow-keywords;
}

/* 首屏 */
.page-faq .faq-hero {
  position: relative;
  display: grid;
  gap: clamp(1.5rem, 4vw, 3rem);
  align-items: end;
  padding-top: clamp(1rem, 2.5vw, 1.75rem);
  padding-bottom: clamp(2rem, 6vw, 4rem);
}

.page-faq .faq-hero::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: min(100%, 34rem);
  height: 2px;
  background: linear-gradient(90deg, var(--cyan) 0%, var(--cyan) 42%, var(--lava) 100%);
  opacity: .85;
}

.page-faq .faq-hero h1 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(2rem, 6.2vw, 4.2rem);
  line-height: 1.05;
  letter-spacing: -0.02em;
  margin: .6rem 0 1rem;
  color: var(--white);
  max-width: 20ch;
}

.page-faq .faq-hero .lead {
  max-width: 56ch;
  margin: 0 0 1.5rem;
  color: var(--muted);
}

.page-faq .faq-hero-links {
  display: flex;
  flex-wrap: wrap;
  gap: .75rem;
}

.page-faq .faq-hero-media {
  margin: 0;
  width: 100%;
  aspect-ratio: 3 / 2;
  background: var(--ink-deep);
  clip-path: polygon(0 0, 100% 0, 100% 84%, 0 100%);
}

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

@media (min-width: 60rem) {
  .page-faq .faq-hero {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, .9fr);
  }
  .page-faq .faq-hero-media {
    aspect-ratio: 3 / 2;
  }
}

/* 主体两栏 */
.page-faq .faq-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--faq-gap);
  padding-top: clamp(2rem, 5vw, 3.25rem);
  border-top: 1px solid var(--line);
}

@media (min-width: 62rem) {
  .page-faq .faq-layout {
    grid-template-columns: var(--faq-rail) minmax(0, 1fr);
    gap: clamp(2rem, 5vw, 4.5rem);
  }
}

/* 索引 */
.page-faq .faq-index {
  min-width: 0;
}

.page-faq .faq-index-title {
  font-family: var(--font-mono);
  font-size: .78rem;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--cyan);
  margin: 0;
}

.page-faq .faq-index-list {
  list-style: none;
  margin: 1rem 0 1.25rem;
  padding: 0;
  border-left: 1px solid var(--line);
}

.page-faq .faq-index-list a {
  display: block;
  padding: .58rem .5rem .58rem 1rem;
  margin-left: -1px;
  border-left: 2px solid transparent;
  color: var(--muted);
  font-size: .92rem;
  line-height: 1.4;
  text-decoration: none;
  transition: color .25s var(--ease), border-color .25s var(--ease);
}

.page-faq .faq-index-list a:hover,
.page-faq .faq-index-list a:focus-visible {
  color: var(--white);
  border-left-color: var(--cyan);
}

@media (min-width: 62rem) {
  .page-faq .faq-index {
    position: sticky;
    top: 6.5rem;
    align-self: start;
  }
}

@media (max-width: 61.98rem) {
  .page-faq .faq-index-list {
    display: flex;
    gap: .25rem;
    border-left: 0;
    border-top: 1px solid var(--line);
    overflow-x: auto;
    scrollbar-width: thin;
  }
  .page-faq .faq-index-list a {
    white-space: nowrap;
    border-left: 0;
    border-bottom: 2px solid transparent;
    padding: .7rem .85rem;
    margin-left: 0;
  }
  .page-faq .faq-index-list a:hover,
  .page-faq .faq-index-list a:focus-visible {
    border-bottom-color: var(--cyan);
  }
}

/* 分组 */
.page-faq .faq-flow {
  min-width: 0;
}

.page-faq .faq-group {
  scroll-margin-top: 6.5rem;
  padding-bottom: clamp(2rem, 4.5vw, 3rem);
}

.page-faq .faq-group + .faq-group {
  padding-top: clamp(2rem, 4.5vw, 3rem);
  border-top: 1px solid var(--line);
}

.page-faq .faq-group:last-child {
  padding-bottom: 0;
}

.page-faq .faq-group-head {
  max-width: 62ch;
}

.page-faq .faq-group-head h2 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.45rem, 3.6vw, 2.25rem);
  line-height: 1.15;
  letter-spacing: -0.015em;
  color: var(--white);
  margin: 0 0 .55rem;
  transition: color .3s var(--ease);
}

.page-faq .faq-group:target .faq-group-head h2 {
  color: var(--cyan);
}

.page-faq .faq-group-head p {
  margin: 0;
  color: var(--muted);
  font-size: .95rem;
}

.page-faq .faq-group-head a {
  color: var(--cyan-soft);
  text-decoration: none;
  border-bottom: 1px solid var(--line);
  transition: border-color .25s var(--ease), color .25s var(--ease);
}

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

/* 问题条目 */
.page-faq .faq-list {
  margin-top: clamp(1rem, 2.5vw, 1.75rem);
  border-top: 1px solid var(--line);
}

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

.page-faq .faq-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: var(--cyan);
  transform: scaleY(0);
  transform-origin: top center;
  transition: transform .35s var(--ease);
}

.page-faq .faq-item[open]::before {
  transform: scaleY(1);
}

.page-faq .faq-item summary {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  gap: clamp(.7rem, 2vw, 1.4rem);
  align-items: baseline;
  padding: 1.3rem .75rem 1.3rem .95rem;
  cursor: pointer;
  list-style: none;
}

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

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

.page-faq .faq-item summary:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: -3px;
}

.page-faq .faq-num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(1rem, 2.2vw, 1.5rem);
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--line);
  transition: color .3s var(--ease);
}

.page-faq .faq-item[open] .faq-num {
  color: var(--lava);
}

.page-faq .faq-q {
  font-size: clamp(.98rem, 2vw, 1.12rem);
  font-weight: 600;
  line-height: 1.5;
  color: var(--white);
  transition: color .25s var(--ease);
}

.page-faq .faq-toggle {
  position: relative;
  width: 14px;
  height: 14px;
  align-self: center;
  flex: none;
}

.page-faq .faq-toggle::before,
.page-faq .faq-toggle::after {
  content: "";
  position: absolute;
  background: var(--cyan);
  transition: transform .3s var(--ease);
}

.page-faq .faq-toggle::before {
  top: 6px;
  left: 0;
  width: 14px;
  height: 2px;
}

.page-faq .faq-toggle::after {
  top: 0;
  left: 6px;
  width: 2px;
  height: 14px;
}

.page-faq .faq-item[open] .faq-toggle::after {
  transform: scaleY(0);
}

/* 答案 */
.page-faq .faq-a {
  padding: 0 clamp(.75rem, 2vw, 1.5rem) clamp(1.15rem, 2.5vw, 1.6rem) var(--faq-pad-left);
  color: var(--muted);
  font-size: .95rem;
}

.page-faq .faq-a p {
  margin: 0 0 .75rem;
  max-width: 60ch;
}

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

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

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

/* 步骤型答案 */
.page-faq .faq-steps {
  list-style: none;
  counter-reset: faqstep;
  position: relative;
  margin: .6rem 0 .9rem;
  padding: 0 0 0 1.5rem;
  max-width: 60ch;
}

.page-faq .faq-steps::before {
  content: "";
  position: absolute;
  left: .3rem;
  top: .6rem;
  bottom: .7rem;
  width: 1px;
  background: var(--line);
}

.page-faq .faq-steps li {
  position: relative;
  counter-increment: faqstep;
  padding: .32rem 0;
  font-size: .95rem;
  line-height: 1.6;
}

.page-faq .faq-steps li::before {
  content: "";
  position: absolute;
  left: -1.3rem;
  top: .85rem;
  width: 7px;
  height: 7px;
  background: var(--cyan);
  transform: rotate(45deg);
}

/* 展开高度过渡 */
.page-faq .faq-item::details-content {
  block-size: 0;
  overflow: hidden;
  transition: block-size .35s var(--ease), content-visibility .35s allow-discrete;
}

.page-faq .faq-item[open]::details-content {
  block-size: auto;
}

/* 精度分组配图 */
.page-faq .faq-precision-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1.25rem, 3vw, 2.25rem);
  align-items: start;
}

.page-faq .faq-figure {
  margin: 0;
  width: 100%;
  aspect-ratio: 4 / 3;
  background: var(--ink-deep);
  clip-path: polygon(0 0, 100% 0, 100% 100%, 0 86%);
}

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

@media (min-width: 78rem) {
  .page-faq .faq-precision-grid {
    grid-template-columns: minmax(0, .78fr) minmax(0, 1.22fr);
  }
  .page-faq .faq-precision-grid .faq-list {
    margin-top: 0;
  }
}

/* 降级动效 */
@media (prefers-reduced-motion: reduce) {
  .page-faq .faq-item::before {
    transition: none;
    transform: none;
    opacity: 0;
  }
  .page-faq .faq-item[open]::before {
    opacity: 1;
  }
  .page-faq .faq-num,
  .page-faq .faq-q,
  .page-faq .faq-toggle::before,
  .page-faq .faq-toggle::after,
  .page-faq .faq-index-list a,
  .page-faq .faq-group-head h2,
  .page-faq .faq-item::details-content {
    transition: none;
  }
  .page-faq .faq-item::details-content {
    block-size: auto;
  }
}