.page-about {
  --about-measure: 34em;
  background: var(--ink);
  color: var(--bone);
  overflow-x: clip;
}

.page-about .about-hero {
  padding-block: clamp(18px, 3vw, 32px) clamp(34px, 5vw, 60px);
}

.page-about .about-hero .lede {
  max-width: 30em;
  margin-top: 18px;
  color: var(--mist);
  font-size: 18px;
  line-height: 1.75;
}

.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px 14px;
  margin: clamp(26px, 4vw, 42px) 0 0;
  padding-top: 22px;
  border-top: 1px solid var(--line-soft);
}

.page-about .about-stats .stat {
  min-width: 0;
}

.page-about .about-stats .stat-value {
  display: block;
  margin: 0;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(22px, 3.2vw, 30px);
  line-height: 1.1;
  color: var(--lime);
  letter-spacing: -0.02em;
}

.page-about .about-stats .stat-label {
  display: block;
  margin-top: 6px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--mist);
}

/* 主体：左轨 + 长文 */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
  padding-bottom: clamp(48px, 7vw, 88px);
}

.page-about .about-rail {
  min-width: 0;
}

.page-about .rail-sticky {
  position: static;
}

.page-about .rail-title {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--lime-dim);
}

.page-about .rail-list {
  display: flex;
  gap: 0;
  margin: 0;
  padding: 0 0 2px;
  list-style: none;
  overflow-x: auto;
  border-bottom: 1px solid var(--line-soft);
  scrollbar-width: thin;
}

.page-about .rail-link {
  display: flex;
  flex: 0 0 auto;
  gap: 7px;
  align-items: baseline;
  padding: 10px 12px;
  font-size: 13px;
  line-height: 1.4;
  color: var(--mist);
  text-decoration: none;
  white-space: nowrap;
  border-bottom: 2px solid transparent;
  transition: color 160ms var(--ease), border-color 160ms var(--ease), background-color 160ms var(--ease);
}

.page-about .rail-link:hover,
.page-about .rail-link:focus-visible {
  color: var(--bone);
  background-color: var(--lime-wash);
}

.page-about .rail-link[aria-current="true"] {
  color: var(--bone);
  border-bottom-color: var(--lime);
}

.page-about .rail-num {
  font-size: 11px;
  color: var(--lime-dim);
}

.page-about .rail-link[aria-current="true"] .rail-num {
  color: var(--lime);
}

.page-about .rail-scale {
  display: none;
}

.page-about .rail-scale svg {
  display: block;
  width: 64px;
  height: auto;
}

.page-about .scale-axis,
.page-about .scale-tick line {
  stroke: var(--line);
  stroke-width: 1;
}

.page-about .scale-tick text {
  fill: var(--mist);
  font-family: var(--font-mono);
  font-size: 10px;
}

/* 章节 */
.page-about .about-section {
  padding-block: clamp(40px, 6vw, 68px);
  scroll-margin-top: 96px;
}

.page-about .about-section:first-child {
  padding-top: clamp(20px, 3vw, 32px);
}

.page-about .about-section .section-title {
  max-width: 20em;
  margin: 0 0 22px;
}

.page-about .tone-pitch {
  background: var(--pitch);
  margin-inline: calc(-1 * var(--gutter));
  padding-inline: var(--gutter);
}

.page-about .about-prose p {
  max-width: var(--about-measure);
  margin: 0 0 16px;
  font-size: 16.5px;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .about-prose p:last-child {
  margin-bottom: 0;
}

.page-about .about-quote {
  max-width: 28em;
  margin: 34px 0 0;
  padding: 24px 26px;
  background: var(--paper);
  color: var(--paper-ink);
  font-family: var(--font-serif);
  font-size: 19px;
  line-height: 1.7;
  border-left: 3px solid var(--lime);
}

/* 图片 */
.page-about .about-figure {
  margin: 0 0 26px;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  aspect-ratio: 16 / 9;
  filter: saturate(0.7) contrast(1.03) brightness(0.86);
  border: 1px solid var(--line-faint);
}

.page-about .about-figure--tall img {
  aspect-ratio: 3 / 4;
}

.page-about .about-figure figcaption {
  margin-top: 10px;
  font-family: var(--font-serif);
  font-size: 13px;
  line-height: 1.6;
  color: var(--mist);
}

/* 团队 */
.page-about .team-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
  margin-top: 30px;
}

.page-about .team-card {
  padding-top: 14px;
  border-top: 1px solid var(--line-soft);
}

.page-about .team-head {
  display: flex;
  align-items: baseline;
  gap: 10px;
}

.page-about .team-count {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 26px;
  line-height: 1;
  color: var(--lime);
}

.page-about .team-name {
  margin: 0;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--bone);
}

.page-about .team-card p {
  margin: 9px 0 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--mist);
}

/* 四道工序 */
.page-about .process-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
  align-items: start;
}

.page-about .process-card {
  border-top: 1px solid var(--line-soft);
}

.page-about .process-card:last-child {
  border-bottom: 1px solid var(--line-soft);
}

.page-about .process-card summary {
  display: grid;
  grid-template-columns: 46px minmax(0, 1fr);
  gap: 12px;
  align-items: baseline;
  padding: 18px 0;
  cursor: pointer;
  list-style: none;
}

.page-about .process-card summary::-webkit-details-marker {
  display: none;
}

.page-about .process-card summary:focus-visible {
  outline: 2px solid var(--ember);
  outline-offset: 3px;
}

.page-about .process-card .step-index {
  font-size: 20px;
  color: var(--line);
  transition: color 200ms var(--ease);
}

.page-about .process-card .step-title {
  font-size: 18px;
  font-weight: 500;
  color: var(--bone);
}

.page-about .process-card[open] .step-index {
  color: var(--lime);
}

.page-about .process-card[open] summary {
  padding-bottom: 10px;
}

.page-about .process-card .step-body {
  padding: 0 0 18px 58px;
}

.page-about .process-card .step-body p {
  max-width: 32em;
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--mist);
}

/* 归档事实 */
.page-about .archive-facts {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
  margin: 30px 0 0;
  border-top: 1px solid var(--line-soft);
}

.page-about .archive-fact {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 4px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .archive-fact dt {
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--lime-dim);
  font-family: var(--font-mono);
}

.page-about .archive-fact dd {
  margin: 0;
  font-size: 15.5px;
  color: var(--bone);
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

/* 年份时间线 */
.page-about .timeline {
  margin: 0 0 32px;
  padding: 0;
  list-style: none;
}

.page-about .timeline li {
  display: grid;
  grid-template-columns: 62px minmax(0, 1fr);
  gap: 16px;
  padding: 16px 0;
  border-top: 1px solid var(--line-soft);
}

.page-about .timeline li:last-child {
  border-bottom: 1px solid var(--line-soft);
}

.page-about .t-year {
  font-size: 15px;
  color: var(--lime);
  line-height: 1.6;
}

.page-about .t-text {
  font-size: 15px;
  line-height: 1.75;
  color: var(--mist);
}

/* 结尾入口 */
.page-about .about-next {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 32px;
}

.page-about .about-next .btn {
  text-decoration: none;
}

@media (min-width: 700px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .team-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 26px 24px;
  }

  .page-about .archive-facts {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: 34px;
  }

  .page-about .about-figure {
    margin-bottom: 30px;
  }
}

@media (min-width: 900px) {
  .page-about .about-body {
    grid-template-columns: 152px minmax(0, 1fr);
    gap: 60px;
  }

  .page-about .rail-sticky {
    position: sticky;
    top: 100px;
    padding-top: 6px;
  }

  .page-about .rail-list {
    display: grid;
    gap: 0;
    overflow: visible;
    padding-bottom: 0;
    border-bottom: 0;
    border-top: 1px solid var(--line-soft);
  }

  .page-about .rail-link {
    flex: initial;
    padding: 9px 0 9px 10px;
    white-space: normal;
    border-bottom: 0;
    border-left: 2px solid transparent;
  }

  .page-about .rail-link:hover,
  .page-about .rail-link:focus-visible {
    border-left-color: var(--lime-dim);
  }

  .page-about .rail-link[aria-current="true"] {
    border-left-color: var(--lime);
    border-bottom-color: transparent;
  }

  .page-about .rail-scale {
    display: block;
    margin-top: 34px;
    padding-left: 4px;
    border-top: 1px solid var(--line-soft);
    padding-top: 22px;
  }

  .page-about .about-prose p {
    font-size: 17px;
  }

  .page-about .process-layout {
    grid-template-columns: minmax(0, 1fr) 268px;
    gap: 46px;
  }

  .page-about .process-card .step-body {
    padding-left: 58px;
    padding-right: 8px;
  }

  .page-about .team-grid {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    gap: 20px;
    align-items: start;
  }

  .page-about .team-card:nth-child(1) {
    grid-column: 1 / span 4;
  }

  .page-about .team-card:nth-child(2) {
    grid-column: 6 / span 4;
    margin-top: 30px;
  }

  .page-about .team-card:nth-child(3) {
    grid-column: 10 / span 3;
    margin-top: 8px;
  }

  .page-about .team-card:nth-child(4) {
    grid-column: 3 / span 5;
    margin-top: 4px;
  }

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

  .page-about .archive-fact {
    border-bottom: 0;
    border-top: 1px solid var(--line-soft);
    padding: 16px 0 0;
  }

  .page-about .timeline li {
    grid-template-columns: 84px minmax(0, 1fr);
  }

  .page-about .t-text {
    font-size: 16px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .rail-link,
  .page-about .process-card .step-index {
    transition: none;
  }
}
<<<END>>>