.page-faq {
  --faq-rule: rgba(16, 26, 36, 0.14);
  --faq-accent: var(--signal);
  display: block;
}

.page-faq img {
  max-width: 100%;
  height: auto;
  display: block;
}

.page-faq .crumbs {
  padding-top: clamp(18px, 3vw, 30px);
}

/* ---------- 首屏 ---------- */

.page-faq .faq-hero {
  position: relative;
  padding: clamp(28px, 5vw, 60px) 0 clamp(48px, 7vw, 96px);
  background:
    radial-gradient(120% 90% at 88% 6%, rgba(217, 195, 155, 0.5) 0%, rgba(217, 195, 155, 0) 62%),
    var(--paper);
}

.page-faq .faq-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(28px, 4vw, 56px);
  align-items: end;
}

.page-faq .faq-hero__copy {
  border-left: 3px solid var(--signal);
  padding-left: clamp(16px, 2.4vw, 30px);
}

.page-faq .faq-hero__title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(2.1rem, 7vw, 4.4rem);
  line-height: 1.02;
  letter-spacing: -0.02em;
  color: var(--ink);
  margin: 12px 0 20px;
  text-wrap: balance;
}

.page-faq .faq-hero__lede {
  max-width: 46ch;
  color: var(--ink-70);
}

.page-faq .faq-hero__chips {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.page-faq .faq-hero__chips .chip {
  font-size: 0.8125rem;
  padding: 7px 15px;
}

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

.page-faq .faq-hero__figure img {
  border-radius: var(--r-lg);
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border: 1px solid var(--faq-rule);
}

/* ---------- 双栏骨架 ---------- */

.page-faq .faq-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  grid-template-areas:
    "rail"
    "main";
  gap: clamp(26px, 4vw, 44px);
  padding-bottom: clamp(56px, 8vw, 110px);
}

.page-faq .faq-rail {
  grid-area: rail;
}

.page-faq .faq-rail__label {
  font-size: 0.8125rem;
  letter-spacing: 0.16em;
  color: var(--slate);
  text-transform: uppercase;
  margin: 0 0 12px;
  padding-left: 4px;
}

.page-faq .faq-rail__label::after {
  content: "";
  display: block;
  width: 46px;
  height: 2px;
  margin-top: 8px;
  background: var(--turq);
  border-radius: 2px;
}

.page-faq .faq-rail__list {
  display: flex;
  gap: 10px;
  list-style: none;
  margin: 0;
  padding: 0 0 8px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

.page-faq .faq-rail__link {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  white-space: nowrap;
  padding: 9px 17px;
  border-radius: var(--r-pill);
  border: 1px solid var(--faq-rule);
  background: var(--paper-white);
  color: var(--ink);
  font-size: 0.9375rem;
  text-decoration: none;
  transition: background 0.22s ease, color 0.22s ease, border-color 0.22s ease;
}

.page-faq .faq-rail__link .mono {
  font-size: 0.75rem;
  color: var(--turq);
  transition: color 0.22s ease;
}

.page-faq .faq-rail__link:hover,
.page-faq .faq-rail__link:focus-visible {
  background: var(--deep);
  border-color: var(--deep);
  color: var(--paper-white);
}

.page-faq .faq-rail__link:hover .mono,
.page-faq .faq-rail__link:focus-visible .mono {
  color: var(--lime);
}

.page-faq .faq-main {
  grid-area: main;
  display: block;
  min-width: 0;
}

/* ---------- 分组 ---------- */

.page-faq .faq-group {
  margin-bottom: clamp(56px, 8vw, 108px);
  scroll-margin-top: 130px;
}

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

.page-faq .faq-group--book { --faq-accent: var(--turq); }
.page-faq .faq-group--spec { --faq-accent: var(--signal); }
.page-faq .faq-group--stock { --faq-accent: var(--deep); }
.page-faq .faq-group--report { --faq-accent: var(--ember); }
.page-faq .faq-group--install { --faq-accent: var(--slate); }
.page-faq .faq-group--glossary { --faq-accent: var(--turq); }

.page-faq .faq-group__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 18px;
  padding-bottom: 18px;
  margin-bottom: 4px;
  border-bottom: 1px solid var(--faq-rule);
}

.page-faq .faq-group__index {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 0;
  font-size: 0.8125rem;
  letter-spacing: 0.14em;
  color: var(--faq-accent);
}

.page-faq .faq-group__index::after {
  content: "";
  width: 44px;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
}

.page-faq .faq-group__title {
  margin: 0;
  color: var(--ink);
}

.page-faq .faq-group__note {
  flex-basis: 100%;
  margin: 0;
  max-width: 54ch;
  color: var(--slate);
  font-size: 1rem;
  line-height: 1.8;
}

/* ---------- 折叠问答 ---------- */

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

.page-faq .qa__q {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 20px 6px;
  cursor: pointer;
  list-style: none;
  transition: color 0.22s ease, background 0.22s ease;
}

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

.page-faq .qa__q:hover {
  color: var(--faq-accent);
}

.page-faq .qa__q:focus-visible {
  outline: 2px solid var(--signal);
  outline-offset: -2px;
  border-radius: var(--r-sm);
}

.page-faq .qa__text {
  font-family: var(--font-heavy);
  font-size: clamp(1.02rem, 1.6vw, 1.2rem);
  line-height: 1.55;
  color: var(--ink);
  transition: color 0.22s ease;
}

.page-faq .qa__q:hover .qa__text {
  color: var(--faq-accent);
}

.page-faq .qa__mark {
  position: relative;
  flex: none;
  width: 17px;
  height: 17px;
}

.page-faq .qa__mark::before,
.page-faq .qa__mark::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 50%;
  height: 2px;
  border-radius: 2px;
  background: var(--faq-accent);
  transform: translateY(-50%);
  transition: transform 0.28s ease, opacity 0.28s ease;
}

.page-faq .qa__mark::after {
  transform: translateY(-50%) rotate(90deg);
}

.page-faq .qa[open] .qa__mark::after {
  transform: translateY(-50%) rotate(0deg);
  opacity: 0;
}

.page-faq .qa__inner {
  padding-inline: clamp(0px, 1.6vw, 26px);
}

.page-faq .qa[open] .qa__inner {
  animation: faq-reveal 0.36s cubic-bezier(0.22, 0.7, 0.3, 1) both;
}

.page-faq .qa__inner p {
  margin: 0 0 24px;
  max-width: 64ch;
  font-size: 1rem;
  line-height: 1.85;
  color: var(--ink-70);
}

.page-faq .qa__inner a {
  color: var(--deep);
  text-decoration: none;
  border-bottom: 1px solid var(--turq);
}

.page-faq .qa__inner a:hover {
  color: var(--ember);
  border-bottom-color: var(--ember);
}

@keyframes faq-reveal {
  from { opacity: 0; transform: translateY(-7px); }
  to { opacity: 1; transform: none; }
}

/* ---------- 术语表 ---------- */

.page-faq .glossary {
  border-top: 1px solid var(--faq-rule);
  margin-top: 18px;
}

.page-faq .glossary__row {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 6px;
  padding: 18px 8px 18px 16px;
  border-bottom: 1px solid var(--faq-rule);
  transition: background 0.22s ease;
}

.page-faq .glossary__row::before {
  content: "";
  position: absolute;
  left: 0;
  top: 14px;
  bottom: 14px;
  width: 3px;
  border-radius: 3px;
  background: var(--faq-accent);
  transform: scaleY(0);
  transform-origin: top center;
  transition: transform 0.28s ease;
}

.page-faq .glossary__row:hover,
.page-faq .glossary__row:focus-within {
  background: var(--paper-white);
}

.page-faq .glossary__row:hover::before,
.page-faq .glossary__row:focus-within::before {
  transform: scaleY(1);
}

.page-faq .glossary__term {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.95rem;
  letter-spacing: 0.02em;
  color: var(--deep);
}

.page-faq .glossary__def {
  margin: 0;
  font-size: 1rem;
  line-height: 1.8;
  color: var(--ink-70);
}

.page-faq .glossary__link {
  justify-self: start;
  font-size: 0.8125rem;
  color: var(--slate);
  text-decoration: none;
  border-bottom: 1px dashed var(--ink-14);
  padding-bottom: 1px;
  transition: color 0.22s ease, border-color 0.22s ease, opacity 0.22s ease;
}

.page-faq .glossary__link:hover,
.page-faq .glossary__link:focus-visible {
  color: var(--ember);
  border-bottom-color: var(--ember);
}

/* ---------- 结尾帮助区 ---------- */

.page-faq .faq-help {
  background: var(--deep);
  color: var(--paper);
  border-radius: var(--r-lg);
  padding: clamp(28px, 4.6vw, 64px);
  margin-bottom: clamp(48px, 7vw, 96px);
}

.page-faq .faq-help__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 4vw, 52px);
  align-items: center;
}

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

.page-faq .faq-help__figure img {
  border-radius: var(--r-md);
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-faq .faq-help__figure .figure__caption {
  color: rgba(243, 237, 226, 0.66);
  border-top-color: rgba(243, 237, 226, 0.28);
}

.page-faq .faq-help__title {
  color: var(--paper-white);
  margin: 0 0 16px;
}

.page-faq .faq-help__text,
.page-faq .faq-help__prep {
  margin: 0 0 16px;
  max-width: 58ch;
  font-size: 1rem;
  line-height: 1.85;
  color: rgba(243, 237, 226, 0.82);
}

.page-faq .faq-help__prep {
  padding-left: 16px;
  border-left: 2px solid var(--lime);
}

.page-faq .faq-help__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: 26px 0 22px;
}

.page-faq .faq-help__aside {
  margin: 0;
  font-size: 0.875rem;
  line-height: 1.8;
  color: rgba(243, 237, 226, 0.62);
}

.page-faq .faq-help__aside a {
  color: var(--lime);
  text-decoration: none;
  border-bottom: 1px solid rgba(198, 232, 92, 0.5);
}

.page-faq .faq-help__aside a:hover {
  color: var(--paper-white);
  border-bottom-color: var(--paper-white);
}

/* ---------- 响应式 ---------- */

@media (min-width: 720px) {
  .page-faq .glossary__row {
    grid-template-columns: 190px minmax(0, 1fr);
    gap: 4px 30px;
    align-items: baseline;
    padding-inline: 16px 8px;
  }

  .page-faq .glossary__link {
    grid-column: 2 / 3;
    margin-top: 6px;
  }
}

@media (min-width: 880px) {
  .page-faq .faq-hero__grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
  }

  .page-faq .faq-help__grid {
    grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
  }
}

@media (min-width: 1000px) {
  .page-faq .faq-layout {
    grid-template-columns: minmax(0, 1fr) 236px;
    grid-template-areas: "main rail";
    column-gap: clamp(44px, 5vw, 84px);
  }

  .page-faq .faq-rail {
    position: sticky;
    top: 124px;
    align-self: start;
  }

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

  .page-faq .faq-rail__link {
    width: 100%;
    justify-content: flex-start;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-faq .qa[open] .qa__inner {
    animation: none;
  }

  .page-faq .qa__mark::before,
  .page-faq .qa__mark::after,
  .page-faq .glossary__row::before {
    transition: none;
  }
}