.page-about {
  --about-rail-w: 230px;
  --about-rail-gap: 4rem;
}

.page-about .about-shell {
  max-width: var(--shell);
  margin: 0 auto;
  padding: clamp(1.75rem, 4vw, 3.25rem) var(--gutter) clamp(3rem, 6vw, 5rem);
}

/* 面包屑 */
.page-about .breadcrumb {
  margin-bottom: clamp(1.25rem, 3vw, 2rem);
}
.page-about .breadcrumb-list {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  padding: 0;
  margin: 0;
  font-size: 0.8125rem;
  letter-spacing: 0.04em;
  color: var(--bone-dim);
}
.page-about .breadcrumb-list li + li::before {
  content: "/";
  margin-right: 0.4rem;
  color: var(--rock);
}
.page-about .breadcrumb-list a {
  color: var(--bone-dim);
  text-decoration: none;
  transition: color var(--t) var(--ease);
}
.page-about .breadcrumb-list a:hover,
.page-about .breadcrumb-list a:focus-visible {
  color: var(--card-yellow);
}
.page-about .breadcrumb-list [aria-current="page"] {
  color: var(--bone);
}

/* 首屏 */
.page-about .about-hero {
  padding-bottom: clamp(1.75rem, 4vw, 3rem);
  border-bottom: 1px solid var(--bone-soft);
  margin-bottom: clamp(2rem, 4vw, 3.25rem);
}
.page-about .about-hero h1 {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(1.75rem, 4.4vw, 3.125rem);
  line-height: 1.18;
  letter-spacing: -0.01em;
  color: var(--bone);
  margin: 0.75rem 0 1.25rem;
  max-width: 24ch;
}
.page-about .about-lede {
  font-size: clamp(1rem, 1.4vw, 1.125rem);
  line-height: 1.8;
  color: var(--bone-dim);
  max-width: 46ch;
  margin: 0;
}

.page-about .about-figures {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.5rem 2rem;
  margin: 2.5rem 0 0;
  padding-top: 2rem;
  border-top: 1px solid var(--bone-soft);
}
.page-about .figure-cell dt {
  font-size: 0.6875rem;
  letter-spacing: 0.16em;
  color: var(--rock);
  margin-bottom: 0.4rem;
}
.page-about .figure-cell dd {
  margin: 0;
  font-family: var(--font-number);
  font-size: clamp(1.75rem, 3.2vw, 2.5rem);
  font-weight: 700;
  line-height: 1;
  color: var(--card-yellow);
  font-variant-numeric: tabular-nums;
}

/* 双栏骨架 */
.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 2rem;
}

/* 左窄栏目录 */
.page-about .about-rail {
  display: none;
}

/* 正文 */
.page-about .about-body {
  min-width: 0;
}

.page-about .about-section {
  position: relative;
  padding: clamp(1.5rem, 3vw, 2.5rem) 0 clamp(2.25rem, 4vw, 3.25rem);
  border-bottom: 1px solid var(--bone-soft);
  scroll-margin-top: 7rem;
}
.page-about .about-section:last-of-type {
  border-bottom: none;
}

.page-about .section-no {
  display: block;
  font-family: var(--font-number);
  font-size: clamp(2.25rem, 4.5vw, 3.5rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: 0.02em;
  color: var(--clay);
  opacity: 0.55;
  margin-bottom: 0.6rem;
  font-variant-numeric: tabular-nums;
}

.page-about .section-title {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(1.5rem, 2.7vw, 2.125rem);
  line-height: 1.3;
  letter-spacing: -0.01em;
  color: var(--bone);
  margin: 0 0 1.25rem;
  max-width: 24ch;
}

.page-about .prose p {
  font-size: clamp(1rem, 1.15vw, 1.0625rem);
  line-height: 1.85;
  color: var(--bone-dim);
  margin: 0 0 1.2em;
  max-width: 38em;
}
.page-about .prose p:last-child {
  margin-bottom: 0;
}
.page-about .prose strong {
  font-weight: 700;
}

/* 整行引文 */
.page-about .pull-quote {
  font-family: var(--font-serif);
  font-size: clamp(1.25rem, 2.3vw, 1.625rem);
  line-height: 1.55;
  color: var(--bone);
  border-left: 3px solid var(--card-yellow);
  padding: 0.75rem 0 0.75rem 1.5rem;
  margin: 3rem 0 1rem;
  max-width: 30ch;
}

/* 媒体图 */
.page-about .about-figure {
  margin: 2rem 0 2.5rem;
}

/* 团队列表 */
.page-about .team-grid {
  list-style: none;
  margin: 2rem 0 0;
  padding: 0;
  border-top: 1px solid var(--bone-soft);
}
.page-about .team-cell {
  padding: 1.5rem 0;
  border-bottom: 1px solid var(--bone-soft);
}
.page-about .team-role {
  font-family: var(--font-serif);
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--card-yellow);
  margin: 0 0 0.5rem;
}
.page-about .team-cell p {
  margin: 0;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--bone-dim);
  max-width: 42ch;
}

/* 数据旅程时间线 */
.page-about .journey {
  list-style: none;
  margin: 2rem 0 0;
  padding: 0;
}
.page-about .journey-step {
  position: relative;
  padding: 0 0 2rem 2.5rem;
}
.page-about .journey-step::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 22px;
  bottom: -2px;
  width: 2px;
  background: linear-gradient(to bottom, var(--pitch-light), rgba(53, 167, 106, 0.12));
}
.page-about .journey-step::after {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--clay);
  box-shadow: 0 0 0 4px rgba(192, 122, 78, 0.18);
}
.page-about .journey-step:last-child {
  padding-bottom: 0;
}
.page-about .journey-step:last-child::before {
  display: none;
}
.page-about .journey-time {
  display: inline-block;
  font-family: var(--font-number);
  font-size: 0.8125rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--card-yellow);
  margin-bottom: 0.4rem;
  font-variant-numeric: tabular-nums;
}
.page-about .journey-title {
  font-family: var(--font-serif);
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--bone);
  margin: 0 0 0.35rem;
}
.page-about .journey-desc {
  margin: 0;
  font-size: 0.9375rem;
  line-height: 1.75;
  color: var(--bone-dim);
  max-width: 36ch;
}

/* 版本演进 */
.page-about .version-track {
  list-style: none;
  margin: 2rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.9rem;
}
.page-about .version-node {
  position: relative;
  border: 1px solid var(--bone-soft);
  border-radius: var(--radius-md);
  padding: 1.25rem 1.25rem 1.25rem 4.5rem;
  background: rgba(245, 242, 233, 0.03);
  transition: transform var(--t) var(--ease), box-shadow var(--t) var(--ease), border-color var(--t) var(--ease);
}
.page-about .version-node:hover,
.page-about .version-node:focus-within {
  transform: translateY(-2px);
  box-shadow: 0 12px 32px rgba(5, 16, 31, 0.65);
  border-color: var(--clay);
}
.page-about .version-badge {
  position: absolute;
  left: 1.25rem;
  top: 1.25rem;
  width: 2.25rem;
  height: 2.25rem;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--pitch);
  color: var(--bone);
  font-family: var(--font-number);
  font-weight: 700;
  font-size: 0.9375rem;
  letter-spacing: 0.02em;
}
.page-about .version-title {
  font-family: var(--font-serif);
  font-size: 1.0625rem;
  font-weight: 600;
  color: var(--bone);
  margin: 0 0 0.35rem;
}
.page-about .version-desc {
  margin: 0;
  font-size: 0.9375rem;
  line-height: 1.75;
  color: var(--bone-dim);
  max-width: 42ch;
}

/* 协作网络 */
.page-about .network-panel {
  margin-top: 1.75rem;
  padding: clamp(1.25rem, 2.5vw, 1.75rem);
  border-radius: var(--radius-lg);
  background: linear-gradient(150deg, rgba(30, 122, 77, 0.22), rgba(11, 27, 51, 0.4));
  border: 1px solid rgba(53, 167, 106, 0.28);
}
.page-about .network-line {
  margin: 0 0 0.85rem;
  font-size: 0.9375rem;
  line-height: 1.75;
  color: var(--bone);
  padding-left: 1.1rem;
  position: relative;
}
.page-about .network-line::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.6em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--pitch-light);
}
.page-about .network-line:last-child {
  margin-bottom: 0;
}

/* 长期积累 */
.page-about .archive-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.25rem 1.75rem;
  margin: 2rem 0 2.25rem;
}
.page-about .archive-cell {
  padding: 1.25rem 0 1rem;
  border-top: 2px solid var(--card-yellow);
}
.page-about .archive-num {
  margin: 0 0 0.35rem;
  font-family: var(--font-number);
  font-size: clamp(1.875rem, 3.4vw, 2.75rem);
  font-weight: 700;
  line-height: 1;
  color: var(--bone);
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.01em;
}
.page-about .archive-label {
  margin: 0 0 0.5rem;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--clay);
  letter-spacing: 0.04em;
}
.page-about .archive-desc {
  margin: 0;
  font-size: 0.8125rem;
  line-height: 1.7;
  color: var(--bone-dim);
  max-width: 26ch;
}

/* 结尾行动区 */
.page-about .about-cta {
  margin-top: clamp(2rem, 4vw, 3.25rem);
  padding: clamp(1.5rem, 3vw, 2.5rem);
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, rgba(215, 38, 61, 0.16), rgba(11, 27, 51, 0.5));
  border: 1px solid rgba(215, 38, 61, 0.26);
}
.page-about .cta-title {
  font-family: var(--font-serif);
  font-size: clamp(1.25rem, 2.2vw, 1.625rem);
  line-height: 1.35;
  font-weight: 600;
  color: var(--bone);
  margin: 0 0 0.85rem;
  max-width: 22ch;
}
.page-about .cta-copy {
  margin: 0 0 1.5rem;
  font-size: 0.9375rem;
  line-height: 1.8;
  color: var(--bone-dim);
  max-width: 52ch;
}
.page-about .cta-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

/* 桌面栅格：左窄右宽 */
@media (min-width: 900px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: var(--about-rail-gap);
  }
  .page-about .about-rail {
    display: block;
    position: sticky;
    top: 7rem;
    align-self: start;
    padding-right: 0.5rem;
  }
  .page-about .about-figures {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .archive-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1100px) {
  .page-about .archive-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* 左窄栏目录细节 */
.page-about .rail-caption {
  margin: 0 0 1rem;
  font-size: 0.6875rem;
  letter-spacing: 0.2em;
  color: var(--rock);
}
.page-about .rail-track {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.15rem;
  counter-reset: rail;
}
.page-about .rail-track a {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  padding: 0.5rem 0.5rem 0.5rem 0.85rem;
  color: var(--bone-dim);
  text-decoration: none;
  font-size: 0.875rem;
  line-height: 1.4;
  border-left: 2px solid transparent;
  border-radius: 0 var(--radius-pill) var(--radius-pill) 0;
  transition: color var(--t) var(--ease), border-color var(--t) var(--ease), background-color var(--t) var(--ease);
}
.page-about .rail-track a:hover,
.page-about .rail-track a:focus-visible {
  color: var(--bone);
  border-left-color: var(--clay);
  background: rgba(245, 242, 233, 0.04);
}
.page-about .rail-num {
  font-family: var(--font-number);
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--clay);
  letter-spacing: 0.04em;
  font-variant-numeric: tabular-nums;
}

@media (prefers-reduced-motion: reduce) {
  .page-about .version-node,
  .page-about .rail-track a,
  .page-about .breadcrumb-list a {
    transition: none;
  }
  .page-about .version-node:hover,
  .page-about .version-node:focus-within {
    transform: none;
  }
}
<<<END>>>