.page-about {
  --about-tick: rgba(216, 211, 200, 0.65);
  --about-soft: rgba(200, 163, 83, 0.1);
  background: var(--hth-paper);
  color: var(--hth-ink);
  overflow-x: hidden;
}

.page-about .hth-breadcrumb {
  padding: 22px 0 6px;
  font-size: 0.875rem;
  color: var(--hth-gray);
}

/* ---------- 封面条 ---------- */

.page-about .archive-cover {
  position: relative;
  padding-bottom: 52px;
  border-bottom: 1px solid var(--hth-line);
  background-image: linear-gradient(180deg, rgba(200, 163, 83, 0.16), rgba(247, 245, 240, 0) 64%);
}

.page-about .archive-cover::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 8px;
  background-image: repeating-linear-gradient(90deg, var(--about-tick) 0 1px, transparent 1px 14px);
  pointer-events: none;
}

.page-about .archive-cover__inner {
  display: grid;
  gap: 32px;
  padding-top: 12px;
}

.page-about .archive-cover__kicker {
  display: inline-block;
  margin: 0 0 16px;
  padding: 4px 10px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  color: var(--hth-red-deep);
  background: var(--hth-sand-pale);
}

.page-about .archive-cover__title {
  margin: 0 0 18px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.9rem, 7.2vw, 3.5rem);
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--hth-ink);
}

.page-about .archive-cover__lede {
  margin: 0;
  max-width: 40ch;
  font-size: 1.0625rem;
  line-height: 1.85;
  color: var(--hth-ink);
}

.page-about .archive-cover__facts {
  list-style: none;
  margin: 26px 0 0;
  padding: 1px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--hth-line);
  border: 1px solid var(--hth-line);
}

.page-about .archive-cover__facts li {
  background: var(--hth-paper);
  padding: 12px 14px;
  font-size: 0.8125rem;
  line-height: 1.6;
  color: var(--hth-gray);
}

.page-about .arc-num {
  display: block;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--hth-ink);
}

.page-about .archive-cover__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.page-about .archive-cover__media {
  aspect-ratio: 14 / 9;
}

/* ---------- 档案室外壳 ---------- */

.page-about .archive-shell {
  display: grid;
  gap: 36px;
  padding-top: 36px;
  padding-bottom: 72px;
}

.page-about .archive-toc {
  border-top: 2px solid var(--hth-sand);
  padding-top: 14px;
}

.page-about .archive-toc__title {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  color: var(--hth-gray);
}

.page-about .archive-toc__list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .archive-toc__list a {
  display: flex;
  gap: 10px;
  align-items: baseline;
  padding: 9px 10px;
  border-left: 2px solid var(--hth-line);
  color: var(--hth-gray);
  font-size: 0.9375rem;
  line-height: 1.5;
  text-decoration: none;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-about .archive-toc__list a:hover,
.page-about .archive-toc__list a:focus-visible {
  color: var(--hth-red-deep);
  border-left-color: var(--hth-red-deep);
  background: rgba(200, 16, 46, 0.06);
}

.page-about .archive-toc__list a[aria-current="true"] {
  color: var(--hth-ink);
  border-left-color: var(--hth-sand);
  background: var(--hth-sand-pale);
}

.page-about .toc-no {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 0.8125rem;
  color: var(--hth-red);
  flex: 0 0 auto;
}

.page-about .archive-toc__list a[aria-current="true"] .toc-no {
  color: var(--hth-red-deep);
}

.page-about .archive-toc__note {
  margin: 14px 0 0;
  font-size: 0.8125rem;
  line-height: 1.7;
  color: var(--hth-gray);
}

@media (max-width: 999px) {
  .page-about .archive-toc__list {
    display: flex;
    gap: 8px;
    overflow-x: auto;
    padding-bottom: 6px;
    scrollbar-width: thin;
  }

  .page-about .archive-toc__list li {
    flex: 0 0 auto;
  }

  .page-about .archive-toc__list a {
    border-left: none;
    border-bottom: 2px solid var(--hth-line);
    white-space: nowrap;
  }

  .page-about .archive-toc__list a:hover,
  .page-about .archive-toc__list a:focus-visible,
  .page-about .archive-toc__list a[aria-current="true"] {
    border-left: none;
    border-bottom-color: var(--hth-red-deep);
  }
}

/* ---------- 章节 ---------- */

.page-about .archive-section {
  padding-top: 40px;
  margin-top: 40px;
  border-top: 1px solid var(--hth-line);
  scroll-margin-top: 120px;
}

.page-about .archive-section:first-child {
  padding-top: 0;
  margin-top: 0;
  border-top: none;
}

.page-about .archive-section .hth-section-head {
  margin-bottom: 20px;
}

.page-about .archive-section .hth-section-head__title {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: clamp(1.35rem, 3.2vw, 2.05rem);
  line-height: 1.32;
  margin: 8px 0;
  color: var(--hth-ink);
}

.page-about .archive-section .hth-section-head__title::after {
  content: "";
  display: block;
  width: 0;
  height: 2px;
  margin-top: 0;
  background: var(--hth-sand);
  transition: width 180ms var(--ease), margin-top 180ms var(--ease);
}

.page-about .archive-section:target .hth-section-head__title::after {
  width: 64px;
  margin-top: 10px;
}

.page-about .archive-section .hth-section-head__note {
  margin: 0;
  font-size: 0.8125rem;
  color: var(--hth-gray);
}

.page-about .archive-body .hth-prose {
  font-size: 1rem;
  line-height: 1.9;
}

.page-about .archive-body .hth-prose p {
  margin: 0 0 18px;
}

.page-about .archive-body .hth-prose a {
  color: var(--hth-red-deep);
  text-decoration: none;
  border-bottom: 1px solid var(--hth-line);
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.page-about .archive-body .hth-prose a:hover,
.page-about .archive-body .hth-prose a:focus-visible {
  border-bottom-color: var(--hth-red-deep);
}

/* ---------- 三层收录口径 ---------- */

.page-about .strata {
  display: grid;
  gap: 1px;
  margin: 24px 0 20px;
  background: var(--hth-line);
  border: 1px solid var(--hth-line);
}

.page-about .strata__layer {
  position: relative;
  padding: 22px 20px 24px;
  background: var(--hth-paper);
  transition: background-color var(--dur) var(--ease);
}

.page-about .strata__layer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--hth-red);
  transition: width 180ms var(--ease);
}

.page-about .strata__layer:hover::before,
.page-about .strata__layer:focus-within::before,
.page-about .strata__layer:focus::before {
  width: 100%;
}

.page-about .strata__layer:hover,
.page-about .strata__layer:focus-visible {
  background: rgba(232, 220, 194, 0.4);
}

.page-about .strata__layer:focus-visible {
  outline: 2px solid var(--hth-sand);
  outline-offset: 2px;
}

.page-about .strata__no {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  color: var(--hth-red-deep);
}

.page-about .strata__title {
  margin: 10px 0 8px;
  font-family: var(--font-heading);
  font-size: 1.125rem;
  font-weight: 700;
  line-height: 1.4;
  color: var(--hth-ink);
}

.page-about .strata__desc {
  margin: 0 0 16px;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--hth-gray);
}

.page-about .strata__fields {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--hth-line);
}

.page-about .strata__fields li {
  padding: 8px 0;
  border-bottom: 1px dashed var(--hth-line);
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  line-height: 1.6;
  color: var(--hth-ink);
}

.page-about .strata__fields li:last-child {
  border-bottom: none;
}

/* ---------- 横向时间轴 ---------- */

.page-about .timeline {
  margin-top: 24px;
  overflow-x: auto;
  overscroll-behavior-inline: contain;
  scroll-snap-type: x proximity;
  border-top: 1px solid var(--hth-line);
  border-bottom: 1px solid var(--hth-line);
  background-image: repeating-linear-gradient(90deg, var(--about-tick) 0 1px, transparent 1px 20px);
  background-repeat: repeat-x;
  background-position: 0 100%;
  background-size: auto 10px;
  scrollbar-width: thin;
}

.page-about .timeline:focus-visible {
  outline: 2px solid var(--hth-sand);
  outline-offset: 2px;
}

.page-about .timeline__track {
  list-style: none;
  margin: 0;
  padding: 0 0 20px;
  display: flex;
  min-width: max-content;
}

.page-about .timeline__item {
  position: relative;
  flex: 0 0 236px;
  padding: 22px 20px 4px;
  border-left: 1px solid var(--hth-line);
  scroll-snap-align: start;
  transition: background-color var(--dur) var(--ease);
}

.page-about .timeline__item::after {
  content: "";
  position: absolute;
  left: -1px;
  bottom: -20px;
  width: 12px;
  height: 2px;
  background: var(--hth-sand);
}

.page-about .timeline__item:hover {
  background: var(--about-soft);
}

.page-about .timeline__ver {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  font-variant-numeric: tabular-nums;
  color: var(--hth-red);
}

.page-about .timeline__label {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.0625rem;
  line-height: 1.4;
  color: var(--hth-ink);
}

.page-about .timeline__desc {
  margin: 0;
  font-size: 0.875rem;
  line-height: 1.75;
  color: var(--hth-gray);
}

.page-about .timeline__hint {
  margin: 12px 0 0;
  font-size: 0.8125rem;
  color: var(--hth-gray);
}

.page-about .timeline-media {
  margin: 28px 0 0;
}

/* ---------- 团队分工 ---------- */

.page-about .crew {
  display: grid;
  gap: 28px;
  margin-top: 22px;
}

.page-about .crew-table {
  margin-top: 8px;
  width: 100%;
}

.page-about .crew-table__caption {
  caption-side: top;
  text-align: left;
  padding-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  color: var(--hth-gray);
}

.page-about .crew-table td {
  font-size: 0.9375rem;
  line-height: 1.7;
  vertical-align: top;
}

.page-about .crew-table td:first-child {
  font-weight: 700;
  color: var(--hth-ink);
  white-space: nowrap;
}

.page-about .crew-table .mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  color: var(--hth-red-deep);
  white-space: nowrap;
}

.page-about .crew__media {
  aspect-ratio: 4 / 3;
}

/* ---------- 纠错步骤条 ---------- */

.page-about .steps {
  list-style: none;
  margin: 24px 0 20px;
  padding: 1px;
  display: grid;
  gap: 1px;
  background: var(--hth-line);
  border: 1px solid var(--hth-line);
}

.page-about .steps li {
  background: var(--hth-paper);
  padding: 18px 16px 20px;
  transition: background-color var(--dur) var(--ease);
}

.page-about .steps li:hover {
  background: rgba(232, 220, 194, 0.5);
}

.page-about .steps__no {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  color: var(--hth-red-deep);
}

.page-about .steps__title {
  margin: 0 0 6px;
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 700;
  color: var(--hth-ink);
}

.page-about .steps__desc {
  margin: 0;
  font-size: 0.875rem;
  line-height: 1.75;
  color: var(--hth-gray);
}

/* ---------- 深色协作面板 ---------- */

.page-about .scope-panel {
  margin-top: 22px;
  padding: 28px 22px;
}

.page-about .scope-panel__lede {
  margin: 0;
  max-width: 58ch;
  font-size: 1rem;
  line-height: 1.9;
  color: rgba(247, 245, 240, 0.9);
}

.page-about .scope-grid {
  display: grid;
  gap: 22px;
  margin-top: 24px;
}

.page-about .scope-cell {
  padding-top: 16px;
  border-top: 1px solid rgba(200, 163, 83, 0.45);
}

.page-about .scope-num {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--hth-sand);
}

.page-about .scope-label {
  margin: 0;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: rgba(247, 245, 240, 0.82);
}

/* ---------- 相关入口与信任条 ---------- */

.page-about .about-next {
  margin-top: 44px;
  padding-top: 20px;
  border-top: 2px solid var(--hth-sand);
}

.page-about .about-next__title {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  color: var(--hth-gray);
}

.page-about .about-next__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--hth-line);
  border: 1px solid var(--hth-line);
}

.page-about .about-next__list a {
  display: block;
  padding: 13px 14px;
  background: var(--hth-paper);
  color: var(--hth-ink);
  font-size: 0.9375rem;
  line-height: 1.6;
  text-decoration: none;
  transition: background-color var(--dur) var(--ease), color var(--dur) var(--ease), padding-left var(--dur) var(--ease);
}

.page-about .about-next__list a:hover,
.page-about .about-next__list a:focus-visible {
  background: var(--hth-red);
  color: var(--hth-paper);
  padding-left: 20px;
}

.page-about .about-trust {
  margin-top: 36px;
  padding: 20px 18px;
  border-left: 3px solid var(--hth-grass);
  background: rgba(232, 220, 194, 0.42);
}

.page-about .about-trust p {
  margin: 0;
  max-width: 68ch;
  font-size: 0.875rem;
  line-height: 1.9;
  color: var(--hth-gray);
}

/* ---------- 媒体查询 ---------- */

@media (min-width: 620px) {
  .page-about .archive-cover__inner {
    gap: 36px;
  }

  .page-about .strata {
    gap: 0;
  }

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

  .page-about .scope-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 28px;
  }
}

@media (min-width: 760px) {
  .page-about .strata {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .steps {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .archive-cover {
    padding-bottom: 64px;
  }

  .page-about .archive-cover__inner {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 52px;
    align-items: end;
  }

  .page-about .archive-cover__media {
    aspect-ratio: 4 / 3;
  }

  .page-about .crew {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 40px;
    align-items: start;
  }
}

@media (min-width: 1000px) {
  .page-about .archive-shell {
    grid-template-columns: minmax(0, 3fr) minmax(0, 9fr);
    gap: 60px;
    padding-top: 44px;
  }

  .page-about .archive-toc {
    position: sticky;
    top: 104px;
    align-self: start;
  }

  .page-about .archive-section {
    padding-top: 52px;
    margin-top: 52px;
  }

  .page-about .archive-section:first-child {
    padding-top: 0;
    margin-top: 0;
  }

  .page-about .strata__layer {
    padding: 26px 22px 28px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .archive-toc__list a,
  .page-about .strata__layer,
  .page-about .strata__layer::before,
  .page-about .timeline__item,
  .page-about .steps li,
  .page-about .about-next__list a,
  .page-about .archive-section .hth-section-head__title::after {
    transition: none;
  }
}