/* ===== 知识中心 /knowledge/ ===== */

.page-faq {
  --faq-axis: rgba(138, 160, 192, 0.16);
  overflow-x: clip;
}

/* —— 首屏 —— */
.page-faq .faq-hero {
  position: relative;
  overflow: hidden;
}

.page-faq .faq-hero::before {
  content: "";
  position: absolute;
  top: -140px;
  left: -10%;
  right: -10%;
  height: 420px;
  background:
    radial-gradient(52% 100% at 22% 42%, rgba(61, 242, 208, 0.13), transparent 68%),
    radial-gradient(40% 90% at 84% 8%, rgba(243, 178, 63, 0.09), transparent 70%);
  pointer-events: none;
}

.page-faq .faq-hero .shell {
  position: relative;
  z-index: 1;
}

.page-faq .faq-hero__title {
  font-family: var(--font-display);
  font-weight: 250;
  font-size: clamp(32px, 6.2vw, 86px);
  line-height: 1.04;
  letter-spacing: -0.015em;
  color: var(--paper);
  max-width: 19ch;
  margin: clamp(14px, 2vw, 22px) 0 clamp(16px, 2.4vw, 26px);
}

.page-faq .faq-hero__lede {
  max-width: 60ch;
  margin: 0;
  color: var(--steel);
  font-size: clamp(15px, 1.55vw, 17px);
  line-height: 1.85;
}

.page-faq .faq-hero__console {
  margin-top: clamp(26px, 3.6vw, 46px);
  border-radius: 14px;
  overflow: hidden;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.page-faq .faq-hero__console .console__cell {
  padding: clamp(14px, 2vw, 22px);
}

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

/* —— 查阅区 —— */
.page-faq .faq-desk__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px 22px;
  margin-bottom: clamp(20px, 3vw, 34px);
}

.page-faq .faq-desk__hint {
  margin: 0;
  color: var(--steel);
  font-size: 14px;
  line-height: 1.7;
}

.page-faq .faq-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 32px);
  align-items: start;
}

@media (min-width: 920px) {
  .page-faq .faq-layout {
    grid-template-columns: 236px minmax(0, 1fr);
    gap: clamp(28px, 3.6vw, 56px);
  }
}

/* 分类索引 */
.page-faq .faq-index {
  border: 1px solid var(--hairline);
  border-radius: 16px;
  background: rgba(11, 24, 48, 0.72);
  padding: clamp(12px, 1.8vw, 18px);
  min-width: 0;
}

@media (min-width: 920px) {
  .page-faq .faq-index {
    position: sticky;
    top: calc(var(--header-h) + 22px);
    backdrop-filter: blur(10px);
  }
}

.page-faq .faq-index__list {
  display: flex;
  gap: 8px;
  margin: 10px 0 0;
  padding: 2px 2px 10px;
  max-width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

@media (min-width: 920px) {
  .page-faq .faq-index__list {
    flex-direction: column;
    overflow-x: visible;
    padding-bottom: 2px;
  }
}

.page-faq .faq-index__list .filter-btn {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  white-space: nowrap;
  border: 1px solid var(--hairline);
  border-radius: 999px;
  background: rgba(61, 242, 208, 0.04);
  color: var(--paper);
  font-family: var(--font-body);
  font-size: 13px;
  line-height: 1.2;
  padding: 9px 15px;
  cursor: pointer;
  transition: border-color 200ms ease, background 200ms ease, color 200ms ease;
}

.page-faq .faq-index__list .filter-btn:hover {
  border-color: var(--glass-line);
}

.page-faq .faq-index__list .filter-btn:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
}

.page-faq .faq-index__list .filter-btn[aria-pressed="true"] {
  border-color: var(--cyan);
  background: rgba(61, 242, 208, 0.14);
  color: var(--cyan);
}

.page-faq .faq-index__count {
  font-family: var(--font-data);
  font-size: 11px;
  letter-spacing: 0.04em;
  color: var(--steel);
}

.page-faq .faq-index__list .filter-btn[aria-pressed="true"] .faq-index__count {
  color: var(--cyan);
}

@media (min-width: 920px) {
  .page-faq .faq-index__list .filter-btn {
    width: 100%;
    justify-content: space-between;
    border-radius: 10px;
  }
}

.page-faq .faq-index .filter-status {
  margin: 8px 2px 0;
  font-family: var(--font-data);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--steel);
}

/* —— 问答流 —— */
.page-faq .faq-stream {
  min-width: 0;
}

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

.page-faq .qa:first-of-type {
  border-top: 1px solid var(--faq-axis);
}

.page-faq .qa[hidden] {
  display: none;
}

.page-faq .qa__q {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto auto;
  align-items: center;
  gap: clamp(10px, 1.8vw, 20px);
  padding: clamp(16px, 2.2vw, 24px) 2px;
  cursor: pointer;
  list-style: none;
}

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

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

.page-faq .qa__num {
  font-family: var(--font-data);
  font-weight: 200;
  font-size: clamp(22px, 2.8vw, 40px);
  line-height: 1;
  min-width: 2ch;
  color: rgba(138, 160, 192, 0.38);
  font-variant-numeric: tabular-nums;
  transition: color 240ms ease;
}

.page-faq .qa[open] .qa__num {
  color: var(--cyan);
}

.page-faq .qa__title {
  font-family: var(--font-body);
  font-weight: 500;
  font-size: clamp(15px, 1.6vw, 18px);
  line-height: 1.5;
  color: var(--paper);
  transition: color 200ms ease;
}

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

.page-faq .qa__tag {
  font-family: var(--font-data);
  font-size: 10px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--steel);
  border: 1px solid var(--hairline);
  border-radius: 999px;
  padding: 4px 10px;
  white-space: nowrap;
  transition: color 240ms ease, border-color 240ms ease;
}

.page-faq .qa[open] .qa__tag {
  color: var(--cyan);
  border-color: var(--glass-line);
}

.page-faq .qa__q::after {
  content: "+";
  font-family: var(--font-data);
  font-size: clamp(16px, 1.8vw, 20px);
  line-height: 1;
  color: var(--steel);
  transition: color 240ms ease;
}

.page-faq .qa[open] .qa__q::after {
  content: "−";
  color: var(--cyan);
}

.page-faq .qa__body {
  position: relative;
  margin: 0;
  padding: 2px 0 clamp(18px, 2.4vw, 28px) clamp(18px, 2.6vw, 40px);
  max-width: 66ch;
}

.page-faq .qa__body::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 14px;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan), rgba(61, 242, 208, 0.05));
  transform: scaleY(0);
  transform-origin: top center;
}

.page-faq .qa[open] .qa__body::before {
  animation: faq-line-grow 460ms cubic-bezier(0.22, 0.8, 0.3, 1) forwards;
}

@keyframes faq-line-grow {
  from { transform: scaleY(0); }
  to { transform: scaleY(1); }
}

.page-faq .qa__body p {
  margin: 0;
  color: var(--steel);
  font-size: clamp(14px, 1.5vw, 16px);
  line-height: 1.85;
}

.page-faq .qa__body a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(61, 242, 208, 0.35);
}

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

.page-faq .qa__body a:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
}

/* —— 插图 —— */
.page-faq .faq-figure {
  margin: clamp(22px, 3vw, 36px) 0;
}

.page-faq .faq-figure .media-frame {
  border-radius: 14px;
  overflow: hidden;
  border: 1px solid var(--hairline);
}

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

.page-faq .faq-figure figcaption {
  margin-top: 10px;
  font-family: var(--font-data);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--steel);
}

/* —— 窄屏收敛 —— */
@media (max-width: 639px) {
  .page-faq .qa__tag {
    display: none;
  }

  .page-faq .qa__q {
    gap: 12px;
  }

  .page-faq .qa__body {
    padding-left: 16px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-faq .qa[open] .qa__body::before {
    animation: none;
    transform: scaleY(1);
  }

  .page-faq .qa__num,
  .page-faq .qa__title,
  .page-faq .qa__tag,
  .page-faq .qa__q::after {
    transition: none;
  }
}