.page-about {
  background: var(--night);
}

.page-about .num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

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

.page-about .about-hero__inner {
  padding-block: 28px 52px;
}

.page-about .about-hero .crumbs {
  margin-bottom: 26px;
}

.page-about .about-hero__title {
  margin: 10px 0 0;
  color: var(--white);
}

.page-about .about-hero__lead {
  max-width: 54ch;
  margin: 18px 0 0;
  color: var(--white);
  font-size: 16px;
  line-height: 1.85;
  letter-spacing: .01em;
}

.page-about .about-hero__panel {
  display: grid;
  gap: 26px;
  margin-top: 36px;
  padding-top: 24px;
  border-top: var(--bw) solid var(--ink);
}

.page-about .about-hero__figure .anchor-number__value {
  display: block;
  color: var(--white);
}

.page-about .about-hero__figure .anchor-number__label {
  display: block;
  margin-top: 12px;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.7;
  letter-spacing: .02em;
  max-width: 30ch;
}

.page-about .about-hero__figure .anchor-number__rule {
  display: block;
  width: 84px;
  height: 4px;
  margin-top: 16px;
  background: var(--net);
}

.page-about .about-hero__facts {
  list-style: none;
  margin: 0;
  padding: 0 0 0 16px;
  border-left: var(--bw) solid var(--night-2);
  display: grid;
  gap: 12px;
}

.page-about .about-hero__facts li {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--white);
  font-size: 14px;
  line-height: 1.6;
}

/* ---------- 纸面主体 ---------- */
.page-about .about-body__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
  padding-block: 36px 64px;
}

.page-about .about-rail {
  align-self: start;
}

.page-about .about-rail__title {
  margin: 0 0 12px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--paper-2);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--muted-ink);
}

.page-about .timeline-rail {
  list-style: none;
  margin: 0;
  padding: 0 0 8px;
  display: flex;
  gap: 10px;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .timeline-rail__item {
  flex: 0 0 auto;
}

.page-about .timeline-rail__link {
  display: flex;
  flex-direction: column;
  gap: 3px;
  min-width: 104px;
  padding: 9px 12px;
  border-left: var(--bw) solid var(--paper-2);
  color: var(--muted-ink);
  text-decoration: none;
  transition: color .12s var(--ease), border-color .12s var(--ease), background-color .12s var(--ease);
}

.page-about .timeline-rail__link:hover,
.page-about .timeline-rail__link:focus-visible {
  background: var(--paper-2);
  color: var(--ink);
}

.page-about .timeline-rail__item.is-current .timeline-rail__link {
  border-left-color: var(--blue);
  color: var(--blue);
}

.page-about .about-rail__year {
  font-size: 14px;
  font-weight: 700;
  letter-spacing: .02em;
}

.page-about .about-rail__label {
  font-size: 12px;
  letter-spacing: .02em;
}

/* ---------- 章节 ---------- */
.page-about .about-sec {
  padding-block: 36px;
  border-top: 1px solid var(--paper-2);
}

.page-about .about-sec:first-child {
  padding-top: 0;
  border-top: 0;
}

.page-about .about-sec__index {
  margin: 0;
  font-size: 13px;
  letter-spacing: .18em;
  color: var(--blue);
}

.page-about .about-sec__title {
  margin: 10px 0 0;
  font-size: clamp(25px, 6.4vw, 40px);
  line-height: 1.2;
  letter-spacing: .05em;
  font-weight: 800;
  color: var(--ink);
}

.page-about .about-sec__lead {
  max-width: var(--measure);
  margin: 14px 0 0;
  font-size: 17px;
  line-height: 1.85;
  color: var(--ink);
}

.page-about .about-sec__tail {
  max-width: var(--measure);
  margin: 26px 0 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--muted-ink);
}

.page-about .prose p {
  max-width: var(--measure);
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink);
}

.page-about .seal-note p {
  margin: 0;
}

.page-about .about-note {
  margin: 22px 0 0;
  max-width: var(--measure);
  font-size: 13px;
  line-height: 1.78;
  letter-spacing: .02em;
}

/* ---------- 自述双栏 ---------- */
.page-about .about-self {
  display: grid;
  gap: 24px;
  margin-top: 22px;
}

.page-about .about-self__frame {
  margin: 0;
  border: var(--bw) solid var(--ink);
  box-shadow: var(--shadow);
  background: var(--ink);
  overflow: hidden;
}

.page-about .about-self__frame img {
  display: block;
  width: 100%;
  aspect-ratio: 4 / 5;
  object-fit: cover;
}

.page-about .media-frame__caption {
  display: block;
  padding: 10px 12px;
  background: var(--ink);
  color: var(--white);
  font-size: 12px;
  line-height: 1.7;
  letter-spacing: .02em;
}

/* ---------- 建档方法 ---------- */
.page-about .about-method__figure {
  margin: 26px 0 0;
  border: var(--bw) solid var(--ink);
  box-shadow: var(--shadow);
  background: var(--ink);
  overflow: hidden;
}

.page-about .about-method__figure img {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.page-about .about-steps {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
  border-top: var(--bw) solid var(--ink);
}

.page-about .about-step {
  display: grid;
  gap: 12px;
  padding: 18px 0;
  border-bottom: 1px solid var(--paper-2);
}

.page-about .about-step__head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin: 0;
}

.page-about .about-step__no {
  font-size: 13px;
  letter-spacing: .12em;
  color: var(--blue);
}

.page-about .about-step__title {
  font-size: 19px;
  font-weight: 700;
  letter-spacing: .03em;
  color: var(--ink);
}

.page-about .about-step__text {
  max-width: 60ch;
  margin: 8px 0 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink);
}

.page-about .about-step__check {
  margin: 0;
  padding: 10px 12px;
  border-left: var(--bw) solid var(--net);
  background: var(--paper-2);
  font-size: 12.5px;
  line-height: 1.72;
  color: var(--muted-ink);
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  position: relative;
  isolation: isolate;
}

.page-about .about-team__bg {
  position: absolute;
  inset: 0;
  z-index: -1;
  margin: 0;
  opacity: .07;
  pointer-events: none;
  overflow: hidden;
}

.page-about .about-team__bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.page-about .about-roster {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .about-roster li {
  padding: 12px 14px;
  border: 1px solid var(--paper-2);
  border-left: var(--bw) solid var(--ink);
  background: var(--white);
}

.page-about .about-roster__head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin: 0;
}

.page-about .about-roster__count {
  font-size: 26px;
  font-weight: 700;
  line-height: 1;
  color: var(--ink);
}

.page-about .about-roster__role {
  font-size: 16px;
  font-weight: 700;
  letter-spacing: .04em;
  color: var(--ink);
}

.page-about .about-roster__text {
  margin: 8px 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted-ink);
}

.page-about .about-checkflow {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--paper-2);
  border: 1px solid var(--paper-2);
}

.page-about .about-checkflow li {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 4px 12px;
  padding: 14px 16px;
  background: var(--paper);
}

.page-about .about-checkflow__step {
  grid-row: 1 / 3;
  align-self: start;
  width: 26px;
  height: 26px;
  display: grid;
  place-items: center;
  background: var(--night);
  color: var(--white);
  font-size: 12px;
}

.page-about .about-checkflow__name {
  font-size: 16px;
  font-weight: 700;
  letter-spacing: .04em;
  color: var(--ink);
}

.page-about .about-checkflow__desc {
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted-ink);
}

.page-about .about-errata-levels {
  display: grid;
  gap: 12px;
  margin-top: 26px;
}

.page-about .about-level__name {
  font-size: 15px;
  font-weight: 700;
  letter-spacing: .06em;
  color: var(--ink);
}

.page-about .about-level__time {
  margin: 6px 0 0;
  font-size: 20px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .about-level__desc {
  margin: 6px 0 0;
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--muted-ink);
}

/* ---------- 版本演进 ---------- */
.page-about .about-versions {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
  border-top: var(--bw) solid var(--ink);
}

.page-about .ver {
  display: grid;
  gap: 10px;
  padding: 20px 0;
  border-bottom: 1px solid var(--paper-2);
  transition: background-color .18s var(--ease), box-shadow .18s var(--ease);
}

.page-about .ver:hover,
.page-about .ver:focus-within,
.page-about .ver:focus {
  background: var(--paper-2);
  box-shadow: inset 3px 0 0 var(--blue);
}

.page-about .ver__mark {
  display: flex;
  align-items: baseline;
  gap: 12px;
}

.page-about .ver__year {
  font-size: clamp(34px, 9vw, 60px);
  font-weight: 700;
  line-height: .95;
  color: var(--ink);
}

.page-about .ver__tag {
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--blue);
}

.page-about .ver__title {
  margin: 0;
  font-size: 19px;
  font-weight: 700;
  letter-spacing: .03em;
  color: var(--ink);
}

.page-about .ver__text {
  max-width: var(--measure);
  margin: 8px 0 0;
  font-size: 15px;
  line-height: 1.82;
  color: var(--ink);
}

/* ---------- 勘误与联系 ---------- */
.page-about .about-contact {
  margin-top: 24px;
  padding: 20px 18px;
  border: var(--bw) solid var(--ink);
  box-shadow: var(--shadow);
  background: var(--white);
}

.page-about .about-contact__intro {
  margin: 0;
  font-size: 15px;
  line-height: 1.82;
  color: var(--ink);
}

.page-about .about-contact__list {
  margin: 20px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--paper-2);
  border-top: 1px solid var(--paper-2);
  border-bottom: 1px solid var(--paper-2);
}

.page-about .about-contact__row {
  display: grid;
  gap: 4px;
  padding: 12px 2px;
  background: var(--white);
}

.page-about .about-contact__row dt {
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--muted-ink);
}

.page-about .about-contact__row dd {
  margin: 0;
  font-size: 15px;
  line-height: 1.6;
  color: var(--ink);
  word-break: break-word;
}

.page-about .about-contact__boundary {
  margin: 16px 0 0;
  font-size: 12.5px;
  line-height: 1.75;
  color: var(--muted-ink);
}

.page-about .about-links {
  display: grid;
  gap: 10px;
  margin-top: 26px;
}

.page-about .about-links__item {
  display: grid;
  gap: 4px;
  padding: 14px 16px;
  border-left: var(--bw) solid var(--blue);
  background: var(--paper-2);
  text-decoration: none;
  transition: background-color .16s var(--ease), border-color .16s var(--ease);
}

.page-about .about-links__item:hover,
.page-about .about-links__item:focus-visible {
  background: var(--white);
  border-left-color: var(--ink);
}

.page-about .about-links__name {
  font-size: 16px;
  font-weight: 700;
  letter-spacing: .04em;
  color: var(--ink);
}

.page-about .about-links__desc {
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted-ink);
}

/* ---------- 尾部入口 ---------- */
.page-about .about-next__inner {
  padding-block: 44px 56px;
}

.page-about .about-next__title {
  margin: 0 0 22px;
  font-size: clamp(22px, 4.6vw, 30px);
  letter-spacing: .06em;
  font-weight: 800;
  color: var(--white);
}

.page-about .about-next__cluster {
  display: grid;
  gap: 14px;
}

.page-about .about-next__cell {
  display: grid;
  gap: 8px;
  padding: 18px 16px;
  border: var(--bw) solid var(--ink);
  background: var(--night-2);
  text-decoration: none;
  transition: transform .18s var(--ease), background-color .18s var(--ease), box-shadow .18s var(--ease);
}

.page-about .about-next__cell:hover,
.page-about .about-next__cell:focus-visible {
  background: var(--ink);
  box-shadow: var(--shadow);
  transform: translate(-2px, -2px);
}

.page-about .about-next__name {
  font-size: 20px;
  font-weight: 700;
  letter-spacing: .05em;
  color: var(--white);
}

.page-about .about-next__desc {
  font-size: 13.5px;
  line-height: 1.78;
  color: var(--muted);
}

.page-about .about-next__cell:hover .about-next__desc,
.page-about .about-next__cell:focus-visible .about-next__desc {
  color: var(--white);
}

/* ---------- 响应式 ---------- */
@media (min-width: 700px) {
  .page-about .about-hero__inner {
    padding-block: 36px 64px;
  }

  .page-about .about-hero__panel {
    grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr);
    align-items: end;
    gap: 40px;
  }

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

  .page-about .about-checkflow {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-errata-levels {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-links,
  .page-about .about-next__cluster {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-step {
    grid-template-columns: minmax(0, 1.7fr) minmax(0, 1fr);
    gap: 28px;
    align-items: start;
  }

  .page-about .about-step__check {
    align-self: stretch;
    display: flex;
    align-items: center;
  }

  .page-about .about-contact__row {
    grid-template-columns: 110px minmax(0, 1fr);
    align-items: baseline;
    gap: 16px;
  }

  .page-about .ver {
    grid-template-columns: 130px minmax(0, 1fr);
    gap: 24px;
    align-items: start;
    padding: 24px 12px 24px 0;
  }

  .page-about .ver__mark {
    flex-direction: column;
    gap: 6px;
  }
}

@media (min-width: 960px) {
  .page-about .about-body__grid {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    gap: 48px 32px;
    padding-block: 56px 88px;
  }

  .page-about .about-rail {
    grid-column: 1 / 4;
    position: sticky;
    top: calc(var(--cmd-h) + 28px);
  }

  .page-about .about-flow {
    grid-column: 4 / 13;
  }

  .page-about .timeline-rail {
    flex-direction: column;
    gap: 4px;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .timeline-rail__link {
    flex-direction: row;
    align-items: baseline;
    gap: 10px;
    min-width: 0;
    padding: 9px 10px;
  }

  .page-about .about-rail__year {
    flex: 0 0 auto;
    min-width: 82px;
    font-size: 12.5px;
  }

  .page-about .about-self {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, .6fr);
    gap: 36px;
    align-items: start;
  }

  .page-about .about-sec {
    padding-block: 52px;
  }

  .page-about .about-sec__lead {
    font-size: 17.5px;
  }

  .page-about .about-roster li {
    padding: 14px 16px;
  }
}

@media (min-width: 1240px) {
  .page-about .about-hero__inner {
    padding-block: 44px 76px;
  }

  .page-about .about-self {
    grid-template-columns: minmax(0, 1.5fr) minmax(0, .5fr);
  }
}
<<<END>>>