/* ================= 知识中心 /knowledge/ ================= */

.page-faq {
  display: block;
  background:
    radial-gradient(1100px 460px at 50% -12%, rgba(63, 224, 208, 0.08), transparent 72%),
    var(--ht-ink);
  color: var(--ht-white);
  overflow-x: hidden;
}

.page-faq .ht-wrap {
  width: min(1180px, 100% - 2 * var(--ht-gutter));
  margin-inline: auto;
}

.page-faq .ht-crumbs {
  padding: 18px 0 0;
}

/* ---------- 首屏 ---------- */

.faq-hero {
  position: relative;
  padding: 22px 0 34px;
  border-bottom: 1px solid var(--ht-line);
  overflow: hidden;
}

.faq-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(36, 52, 75, 0.5) 1px, transparent 1px),
    linear-gradient(90deg, rgba(36, 52, 75, 0.5) 1px, transparent 1px);
  background-size: 46px 46px;
  -webkit-mask-image: linear-gradient(180deg, #000 5%, transparent 82%);
  mask-image: linear-gradient(180deg, #000 5%, transparent 82%);
  pointer-events: none;
}

.faq-hero .ht-wrap {
  position: relative;
  z-index: 1;
}

.faq-hero .ht-eyebrow {
  color: var(--ht-cyan);
}

.faq-hero .ht-h1 {
  margin: 12px 0 16px;
  max-width: 22ch;
  font-size: clamp(28px, 6.4vw, 46px);
  line-height: 1.16;
}

.faq-hero .ht-lede {
  max-width: 66ch;
  margin: 0;
  color: var(--ht-muted);
  font-size: 15px;
  line-height: 1.8;
}

.faq-scope {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  margin: 26px 0 0;
  padding: 0;
  background: var(--ht-line);
  border: 1px solid var(--ht-line);
}

.faq-scope__item {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 14px 12px;
  background: var(--ht-ink-2);
}

.faq-scope__key {
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ht-muted);
}

.faq-scope__val {
  margin: 0;
  font-family: var(--ht-mono);
  font-size: 17px;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  color: var(--ht-lime);
  white-space: nowrap;
}

/* ---------- 章节通用 ---------- */

.page-faq .ht-section.faq-block {
  padding: 44px 0;
}

.faq-block + .faq-block {
  border-top: 1px solid var(--ht-line);
}

.faq-block__head {
  display: grid;
  grid-template-columns: auto 1fr;
  grid-template-areas:
    "num title"
    "num sum";
  column-gap: 14px;
  align-items: start;
  margin-bottom: 26px;
}

.faq-block__num {
  grid-area: num;
  font-family: var(--ht-mono);
  font-size: 26px;
  font-weight: 700;
  line-height: 1;
  color: var(--ht-violet);
  padding-top: 4px;
}

.faq-block__head .ht-h2 {
  grid-area: title;
  margin: 0;
  font-size: clamp(21px, 4.4vw, 30px);
  letter-spacing: -0.01em;
  line-height: 1.25;
}

.faq-block__sum {
  grid-area: sum;
  margin: 8px 0 0;
  max-width: 62ch;
  font-size: 14px;
  line-height: 1.75;
  color: var(--ht-muted);
}

/* ---------- 01 分类宫格 ---------- */

.faq-cats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.faq-cat {
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-height: 118px;
  padding: 16px 14px 14px;
  background: var(--ht-panel);
  border: 1px solid var(--ht-line);
  clip-path: var(--ht-notch-sm);
  color: var(--ht-white);
  text-decoration: none;
  transition: transform var(--ht-ease), border-color var(--ht-ease), background-color var(--ht-ease);
}

.faq-cat:hover,
.faq-cat:focus-visible {
  transform: translateY(-2px);
  border-color: var(--ht-cyan);
  background: var(--ht-ink-2);
}

.faq-cat:focus-visible {
  outline: none;
}

.faq-cat__count {
  font-family: var(--ht-mono);
  font-size: 26px;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  line-height: 1;
  color: var(--ht-cyan);
}

.faq-cat:hover .faq-cat__count,
.faq-cat:focus-visible .faq-cat__count {
  color: var(--ht-lime);
}

.faq-cat__name {
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.01em;
}

.faq-cat__hint {
  margin-top: auto;
  font-size: 12px;
  color: var(--ht-muted);
}

/* ---------- 02 高频问题 ---------- */

.faq-list {
  display: grid;
  gap: 0;
  border-top: 1px solid var(--ht-line);
}

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

.faq-q > summary {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 16px 4px;
  cursor: pointer;
  list-style: none;
  transition: background-color var(--ht-ease);
}

.faq-q > summary::-webkit-details-marker {
  display: none;
}

.faq-q > summary::marker {
  content: "";
}

.faq-q > summary:hover,
.faq-q > summary:focus-visible {
  background: rgba(13, 22, 38, 0.85);
}

.faq-q > summary:focus-visible {
  outline: 2px solid var(--ht-lime);
  outline-offset: -2px;
}

.faq-q__tag {
  flex: 0 0 auto;
  padding: 3px 8px;
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--ht-cyan);
  border: 1px solid rgba(63, 224, 208, 0.4);
  clip-path: var(--ht-notch-sm);
  background: rgba(63, 224, 208, 0.07);
}

.faq-q__text {
  flex: 1 1 auto;
  padding-right: 8px;
  font-size: 15px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--ht-white);
}

.faq-q > summary::after {
  flex: 0 0 auto;
  margin-left: auto;
  font-family: var(--ht-mono);
  font-size: 21px;
  font-weight: 700;
  line-height: 1;
  color: var(--ht-cyan);
  transition: color var(--ht-ease);
}

.faq-q > summary::after {
  content: "+";
}

.faq-q[open] > summary::after {
  content: "\2212";
  color: var(--ht-orange);
}

.faq-q[open] > summary {
  background: var(--ht-ink-2);
}

.faq-q__body {
  padding: 16px 16px 20px;
  background-color: var(--ht-ink-2);
  background-image:
    linear-gradient(rgba(36, 52, 75, 0.45) 1px, transparent 1px),
    linear-gradient(90deg, rgba(36, 52, 75, 0.45) 1px, transparent 1px);
  background-size: 26px 26px;
  border-left: 2px solid var(--ht-lime);
}

.faq-q__body p {
  margin: 0 0 10px;
  max-width: 68ch;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--ht-white);
}

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

.faq-q__body strong {
  color: var(--ht-lime);
  font-weight: 700;
}

.faq-q__body a {
  color: var(--ht-cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.faq-q__body a:hover,
.faq-q__body a:focus-visible {
  color: var(--ht-lime);
}

/* ---------- 03 / 04 步骤说明 ---------- */

.faq-steplayout {
  display: grid;
  gap: 26px;
}

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

.faq-step {
  position: relative;
  display: grid;
  grid-template-columns: 52px minmax(0, 1fr);
  column-gap: 14px;
  padding-bottom: 26px;
}

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

.faq-step::after {
  content: "";
  position: absolute;
  left: 25px;
  top: 56px;
  bottom: 0;
  width: 1px;
  background-image: linear-gradient(var(--ht-line) 50%, transparent 50%);
  background-size: 1px 8px;
}

.faq-step:last-child::after {
  display: none;
}

.faq-step__num {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 52px;
  height: 52px;
  font-family: var(--ht-mono);
  font-size: 20px;
  font-weight: 700;
  line-height: 1;
  color: var(--ht-cyan);
  background: var(--ht-ink-2);
  border: 1px solid var(--ht-line);
  clip-path: var(--ht-notch-sm);
  text-decoration: none;
  transition: color var(--ht-ease), background-color var(--ht-ease), border-color var(--ht-ease);
}

.faq-step__num:hover,
.faq-step__num:focus-visible {
  color: var(--ht-ink);
  background: var(--ht-cyan);
  border-color: var(--ht-cyan);
}

.faq-step:target .faq-step__num {
  color: var(--ht-ink);
  background: var(--ht-lime);
  border-color: var(--ht-lime);
}

.faq-step:target .faq-step__title {
  color: var(--ht-lime);
}

.faq-step:target .faq-step__text {
  color: var(--ht-white);
}

.faq-step__body {
  padding-top: 2px;
}

.faq-step__title {
  margin: 0 0 6px;
  font-size: 17px;
  font-weight: 800;
  letter-spacing: -0.005em;
  line-height: 1.35;
  color: var(--ht-white);
  transition: color var(--ht-ease);
}

.faq-step__text {
  margin: 0;
  max-width: 60ch;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--ht-muted);
  transition: color var(--ht-ease);
}

.faq-figure {
  margin: 0;
}

.faq-figure .ht-figure__caption {
  margin-top: 10px;
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--ht-muted);
}

/* ---------- 05 联系 ---------- */

.faq-block--last {
  padding-bottom: 64px !important;
}

.faq-contact {
  display: grid;
  gap: 14px;
}

.faq-contact__card {
  padding: 20px 18px;
  background: var(--ht-panel);
  border: 1px solid var(--ht-line);
  clip-path: var(--ht-notch-sm);
  transition: border-color var(--ht-ease);
}

.faq-contact__card:hover {
  border-color: var(--ht-cyan);
}

.faq-contact__label {
  margin: 0 0 8px;
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ht-muted);
}

.faq-contact__val {
  margin: 0 0 10px;
  font-family: var(--ht-mono);
  font-size: 18px;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--ht-white);
  word-break: break-all;
}

.faq-contact__note {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.8;
  color: var(--ht-muted);
}

.faq-cta {
  margin: 16px 0 0;
}

.faq-tail {
  margin: 24px 0 0;
  padding-top: 18px;
  border-top: 1px dashed var(--ht-line);
  font-size: 14px;
  line-height: 1.85;
  color: var(--ht-muted);
}

.faq-tail a {
  color: var(--ht-cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.faq-tail a:hover,
.faq-tail a:focus-visible {
  color: var(--ht-lime);
}

/* ---------- 窄屏 ---------- */

@media (max-width: 560px) {
  .faq-hero {
    padding-top: 16px;
  }

  .faq-scope {
    grid-template-columns: 1fr;
  }

  .faq-scope__item {
    flex-direction: row;
    align-items: baseline;
    justify-content: space-between;
    padding: 11px 12px;
  }

  .faq-cats {
    grid-template-columns: 1fr;
  }

  .faq-cat {
    min-height: 0;
  }

  .faq-cat__hint {
    margin-top: 4px;
  }

  .faq-q > summary {
    flex-wrap: wrap;
    align-items: flex-start;
  }

  .faq-q__text {
    flex-basis: 100%;
    order: 3;
    padding-right: 0;
    margin-top: 8px;
  }

  .faq-q > summary::after {
    order: 2;
  }

  .faq-block__head {
    grid-template-columns: 1fr;
    grid-template-areas:
      "num"
      "title"
      "sum";
    row-gap: 8px;
  }

  .faq-block__num {
    padding-top: 0;
  }
}

/* ---------- 平板与桌面 ---------- */

@media (min-width: 720px) {
  .faq-hero {
    padding: 32px 0 46px;
  }

  .page-faq .ht-section.faq-block {
    padding: 60px 0;
  }

  .faq-cats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 14px;
  }

  .faq-block__head {
    column-gap: 20px;
    margin-bottom: 34px;
  }

  .faq-block__num {
    font-size: 34px;
  }

  .faq-q__text {
    font-size: 16px;
  }

  .faq-step {
    grid-template-columns: 58px minmax(0, 1fr);
    column-gap: 20px;
    padding-bottom: 30px;
  }

  .faq-step::after {
    left: 28px;
    top: 62px;
  }

  .faq-step__num {
    width: 58px;
    height: 58px;
    font-size: 22px;
  }

  .faq-step__title {
    font-size: 18px;
  }

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

  .faq-contact__card--wide {
    grid-column: 1 / -1;
  }
}

@media (min-width: 960px) {
  .faq-cats {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }

  .faq-steplayout {
    grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr);
    gap: 42px;
    align-items: start;
  }

  .faq-steplayout--flip {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.5fr);
  }

  .faq-steplayout--flip .faq-figure {
    position: sticky;
    top: 96px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-faq .faq-cat,
  .page-faq .faq-step__num,
  .page-faq .faq-q > summary,
  .page-faq .faq-contact__card {
    transition: none;
  }

  .page-faq .faq-cat:hover,
  .page-faq .faq-cat:focus-visible {
    transform: none;
  }
}