/* ===== 页面作用域：知识中心 /knowledge/ ===== */
.page-faq {
  --faq-line: rgba(23, 26, 31, .14);
  --faq-line-soft: rgba(23, 26, 31, .07);
  --faq-on-ink: rgba(242, 246, 251, .78);
  display: block;
  background: var(--paper);
}

/* ---------- 首屏 ---------- */
.page-faq .faq-hero {
  position: relative;
  overflow: hidden;
  padding-block: clamp(44px, 7vw, 96px) clamp(40px, 6vw, 80px);
  background:
    radial-gradient(112% 82% at 88% 0%, rgba(47, 111, 181, .34), transparent 62%),
    linear-gradient(176deg, var(--ink-900) 0%, #0c2038 58%, var(--ink-900) 100%);
  color: var(--snow);
}

.page-faq .faq-hero__band {
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  opacity: .7;
  background: linear-gradient(180deg,
    var(--flag-blue) 0 22%,
    var(--flag-white) 22% 42%,
    var(--flag-red) 42% 60%,
    var(--flag-green) 60% 80%,
    var(--flag-yellow) 80% 100%);
}

.page-faq .faq-hero__inner {
  position: relative;
  z-index: 1;
  padding-left: clamp(0px, 1.5vw, 20px);
}

.page-faq .faq-hero__crumb {
  margin-bottom: clamp(20px, 3vw, 32px);
}

.page-faq .faq-hero__crumb .arc-breadcrumb__link,
.page-faq .faq-hero__current {
  color: rgba(242, 246, 251, .62);
  font-size: 13px;
  letter-spacing: .1em;
  text-decoration: none;
}

.page-faq .faq-hero__crumb .arc-breadcrumb__link:hover {
  color: var(--flag-yellow);
}

.page-faq .faq-hero__current {
  color: var(--snow);
}

.page-faq .faq-hero__eyebrow {
  color: var(--flag-yellow);
}

.page-faq .faq-hero__title {
  margin: 16px 0 0;
  max-width: 18em;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2.05rem, 5.4vw, 4.2rem);
  line-height: 1.1;
  letter-spacing: .06em;
  color: var(--snow);
}

.page-faq .faq-hero__lede {
  margin: clamp(20px, 3vw, 28px) 0 0;
  max-width: 44em;
  font-size: 17px;
  line-height: 1.85;
  color: var(--faq-on-ink);
}

.page-faq .faq-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px 18px;
  max-width: 760px;
  margin: clamp(30px, 4.5vw, 52px) 0 0;
  padding: 0;
  list-style: none;
}

.page-faq .faq-hero__fact {
  padding: 12px 0 12px 16px;
  border-left: 2px solid rgba(242, 246, 251, .2);
}

.page-faq .faq-hero__num {
  display: block;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(1.25rem, 2.4vw, 1.8rem);
  font-weight: 600;
  letter-spacing: .02em;
  color: var(--snow);
}

.page-faq .faq-hero__label {
  display: block;
  margin-top: 5px;
  font-size: 12px;
  letter-spacing: .14em;
  color: rgba(242, 246, 251, .58);
}

/* ---------- 快速索引 ---------- */
.page-faq .faq-index {
  background: var(--paper-2);
  border-block: 1px solid var(--faq-line);
}

.page-faq .faq-index__head {
  display: grid;
  gap: 20px;
  align-items: end;
  margin-bottom: clamp(24px, 4vw, 42px);
}

.page-faq .faq-index__title {
  margin: 10px 0 0;
  font-family: var(--font-editorial);
  font-weight: 600;
  font-size: clamp(1.4rem, 2.6vw, 2rem);
  line-height: 1.32;
  letter-spacing: .02em;
  color: var(--text);
}

.page-faq .faq-index__search {
  padding: 14px 16px;
  border-radius: var(--radius-md);
  background: var(--paper-card);
  border: 1px solid var(--faq-line);
}

.page-faq .faq-index__search .arc-search__input {
  box-sizing: border-box;
  width: 100%;
  padding: 10px 14px;
  font-family: var(--font-body);
  font-size: 15px;
  color: var(--text);
  background: var(--paper);
  border: 1px solid rgba(23, 26, 31, .18);
  border-radius: var(--radius-sm);
}

.page-faq .faq-index__search .arc-search__input::placeholder {
  color: var(--muted);
}

.page-faq .faq-index__search .arc-search__input:focus-visible {
  outline: 2px solid var(--flag-yellow);
  outline-offset: 1px;
  border-color: var(--flag-blue);
}

.page-faq .faq-index__search .arc-search__status {
  margin: 10px 0 0;
  font-size: 12.5px;
  line-height: 1.6;
  letter-spacing: .03em;
  color: var(--muted);
}

.page-faq .faq-index__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.page-faq .faq-index__item {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 17px 20px 17px 22px;
  border: 1px solid var(--faq-line);
  border-radius: var(--radius-md);
  background: rgba(255, 252, 244, .72);
  color: var(--text);
  text-decoration: none;
  transition: transform .2s ease, border-color .2s ease, background .2s ease;
}

.page-faq .faq-index__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 15px;
  bottom: 15px;
  width: 3px;
  border-radius: 0 3px 3px 0;
  background: var(--flag-blue);
  transition: background .2s ease;
}

.page-faq .faq-index__item:hover,
.page-faq .faq-index__item:focus-visible {
  transform: translateY(-2px);
  border-color: var(--flag-blue);
  background: var(--paper-card);
}

.page-faq .faq-index__item:hover::before,
.page-faq .faq-index__item:focus-visible::before {
  background: var(--flag-red);
}

.page-faq .faq-index__item:focus-visible {
  outline: 2px solid var(--flag-yellow);
  outline-offset: 2px;
}

.page-faq .faq-index__no {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--flag-blue);
}

.page-faq .faq-index__name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 17px;
  letter-spacing: .02em;
  color: var(--text);
}

.page-faq .faq-index__desc {
  font-size: 13.5px;
  line-height: 1.65;
  color: var(--muted);
}

/* ---------- 问答主体布局 ---------- */
.page-faq .faq-answers {
  background: var(--paper);
}

.page-faq .faq-answers__layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(30px, 4vw, 56px);
  align-items: start;
}

/* ---------- 术语速查 ---------- */
.page-faq .faq-glossary {
  order: -1;
}

.page-faq .faq-glossary__inner {
  padding: 22px 20px;
  border-radius: var(--radius-lg);
  border: 1px solid rgba(242, 246, 251, .14);
  background:
    radial-gradient(100% 60% at 0% 0%, rgba(47, 111, 181, .28), transparent 66%),
    var(--ink-900);
  color: var(--snow);
}

.page-faq .faq-glossary__inner .arc-overline {
  color: rgba(242, 246, 251, .56);
}

.page-faq .faq-glossary__title {
  margin: 8px 0 14px;
  font-family: var(--font-editorial);
  font-weight: 600;
  font-size: 1.15rem;
  letter-spacing: .04em;
  color: var(--snow);
}

.page-faq .faq-glossary__list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-faq .faq-glossary__item {
  padding: 12px 0;
  border-top: 1px solid rgba(242, 246, 251, .12);
}

.page-faq .faq-glossary__item:first-child {
  padding-top: 4px;
  border-top: 0;
}

.page-faq .faq-glossary__term {
  display: inline-block;
  padding: 2px 9px;
  border-radius: var(--radius-sm);
  background: rgba(226, 168, 30, .14);
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .04em;
  color: var(--flag-yellow);
}

.page-faq .faq-glossary__def {
  display: block;
  margin-top: 7px;
  font-size: 13.5px;
  line-height: 1.72;
  color: rgba(242, 246, 251, .7);
}

/* ---------- 问答分组 ---------- */
.page-faq .faq-block + .faq-block {
  margin-top: clamp(44px, 6vw, 76px);
}

.page-faq .faq-block__head {
  margin-bottom: 6px;
}

.page-faq .faq-block__title {
  margin: 10px 0 0;
  font-family: var(--font-editorial);
  font-weight: 600;
  font-size: clamp(1.35rem, 2.5vw, 1.95rem);
  line-height: 1.32;
  letter-spacing: .02em;
  color: var(--text);
}

.page-faq .faq-block__note {
  margin: 10px 0 0;
  max-width: 38em;
  font-size: 15px;
  line-height: 1.7;
  color: var(--muted);
}

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

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

.page-faq .faq-item > .faq-item__q {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 15px 6px;
  cursor: pointer;
  list-style: none;
  transition: background .2s ease;
}

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

.page-faq .faq-item > .faq-item__q:hover {
  background: rgba(47, 111, 181, .06);
}

.page-faq .faq-item > .faq-item__q:focus-visible {
  outline: 2px solid var(--flag-yellow);
  outline-offset: -2px;
}

.page-faq .faq-item__no {
  flex: 0 0 auto;
  padding: 3px 9px;
  border-radius: var(--radius-pill);
  background: var(--ink-800);
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--flag-yellow);
  transition: background .2s ease, color .2s ease;
}

.page-faq .faq-item__text {
  flex: 1 1 auto;
  min-width: 0;
  font-size: 16.5px;
  font-weight: 500;
  line-height: 1.62;
  letter-spacing: .01em;
  color: var(--text);
}

.page-faq .faq-item__icon {
  position: relative;
  flex: 0 0 18px;
  width: 18px;
  height: 18px;
  align-self: center;
}

.page-faq .faq-item__icon::before,
.page-faq .faq-item__icon::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 50%;
  height: 2px;
  margin-top: -1px;
  border-radius: 2px;
  background: var(--flag-blue);
  transition: transform .25s ease, background .2s ease;
}

.page-faq .faq-item__icon::after {
  transform: rotate(90deg);
}

.page-faq .faq-item[open] .faq-item__icon::after {
  transform: rotate(0deg);
}

.page-faq .faq-item[open] > .faq-item__q {
  background: rgba(47, 111, 181, .05);
}

.page-faq .faq-item[open] .faq-item__no {
  background: var(--flag-blue);
  color: var(--flag-white);
}

.page-faq .faq-item[open] .faq-item__text {
  font-weight: 600;
  color: var(--ink-900);
}

.page-faq .faq-item__a {
  padding: 2px 6px 20px;
  animation: faq-open .26s ease both;
}

.page-faq .faq-item__a p {
  max-width: var(--measure);
  margin: 0 0 12px;
  font-size: 16.5px;
  line-height: 1.85;
  color: var(--text);
}

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

.page-faq .faq-item__a a {
  color: var(--flag-blue);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
}

.page-faq .faq-item__a a:hover {
  color: var(--flag-red);
}

@keyframes faq-open {
  from { opacity: 0; transform: translateY(-6px); }
  to { opacity: 1; transform: none; }
}

/* ---------- 图片 ---------- */
.page-faq .faq-figure {
  margin: clamp(26px, 3.5vw, 42px) 0 0;
}

.page-faq .faq-figure .arc-figure__img {
  overflow: hidden;
  border: 1px solid var(--faq-line);
  border-radius: var(--radius-md);
}

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

.page-faq .faq-figure .arc-figure__caption {
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 引用格式卡 ---------- */
.page-faq .faq-cite {
  margin-top: clamp(26px, 3.5vw, 38px);
  padding: 20px 22px;
  border: 1px solid var(--faq-line);
  border-left: 3px solid var(--flag-blue);
  border-radius: var(--radius-md);
  background: var(--paper-card);
}

.page-faq .faq-cite__label {
  margin: 0 0 10px;
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--muted);
}

.page-faq .faq-cite__code {
  display: block;
  font-family: var(--font-mono);
  font-size: 13.5px;
  line-height: 1.72;
  color: var(--ink-900);
  word-break: break-word;
}

.page-faq .faq-cite__btn {
  margin-top: 14px;
}

.page-faq .faq-cite__status {
  margin: 9px 0 0;
  min-height: 1.1em;
  font-size: 12.5px;
  letter-spacing: .03em;
  color: var(--flag-green);
}

/* ---------- 咨询引导 ---------- */
.page-faq .faq-assist {
  background:
    radial-gradient(92% 122% at 10% 0%, rgba(47, 111, 181, .26), transparent 62%),
    var(--ink-900);
  color: var(--snow);
}

.page-faq .faq-assist__inner {
  display: grid;
  gap: 26px;
  align-items: center;
}

.page-faq .faq-assist__text .arc-overline {
  color: var(--flag-yellow);
}

.page-faq .faq-assist__title {
  margin: 12px 0 12px;
  font-family: var(--font-editorial);
  font-weight: 600;
  font-size: clamp(1.45rem, 2.8vw, 2.1rem);
  line-height: 1.32;
  letter-spacing: .02em;
  color: var(--snow);
}

.page-faq .faq-assist__para {
  max-width: 42em;
  margin: 0;
  font-size: 16px;
  line-height: 1.82;
  color: var(--faq-on-ink);
}

.page-faq .faq-assist__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-faq .faq-assist__actions .arc-btn--ghost {
  color: var(--snow);
  border-color: rgba(242, 246, 251, .34);
  background: transparent;
}

.page-faq .faq-assist__actions .arc-btn--ghost:hover {
  border-color: var(--flag-yellow);
  color: var(--flag-yellow);
}

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-faq .faq-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-faq .faq-index__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-faq .faq-item__a {
    padding-left: 62px;
    padding-right: 40px;
  }
}

@media (min-width: 900px) {
  .page-faq .faq-index__head {
    grid-template-columns: minmax(0, 1fr) minmax(320px, 400px);
  }

  .page-faq .faq-assist__inner {
    grid-template-columns: minmax(0, 1fr) auto;
  }
}

@media (min-width: 1024px) {
  .page-faq .faq-index__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-faq .faq-index__item:first-child {
    grid-column: span 2;
  }

  .page-faq .faq-answers__layout {
    grid-template-columns: minmax(0, 1fr) 302px;
  }

  .page-faq .faq-glossary {
    order: 0;
  }

  .page-faq .faq-glossary__inner {
    position: sticky;
    top: 104px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-faq .faq-index__item,
  .page-faq .faq-item__icon::before,
  .page-faq .faq-item__icon::after {
    transition: none;
  }

  .page-faq .faq-item__a {
    animation: none;
  }
}