.page-about {
  --about-rail: 216px;
  --about-gap: 40px;
}

.page-about .about-head {
  padding: 22px 0 34px;
}

.page-about .about-head__title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(29px, 6.4vw, 54px);
  line-height: 1.08;
  letter-spacing: -0.02em;
  color: var(--paper);
  margin: 12px 0 18px;
  max-width: 19ch;
}

.page-about .page-head__lede {
  color: var(--stand);
  font-size: 16px;
  line-height: 1.78;
  max-width: 62ch;
  margin: 0;
}

.page-about .about-head__facts {
  display: grid;
  gap: 1px;
  background: var(--metal);
  border: var(--edge);
  margin: 26px 0 0;
  padding: 0;
}

.page-about .about-head__facts > div {
  background: var(--turf);
  padding: 13px 16px 15px;
}

.page-about .about-head__facts dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.26em;
  color: var(--mist);
  margin: 0 0 7px;
}

.page-about .about-head__facts dd {
  margin: 0;
  color: var(--paper);
  font-size: 15px;
  font-weight: 500;
  line-height: 1.55;
}

/* ---------- 轨道外壳 ---------- */

.page-about .about-shell {
  display: grid;
  gap: 26px;
  padding-bottom: 54px;
}

.page-about .track-rail {
  border: var(--edge);
  background: var(--turf);
  box-shadow: var(--paper-shadow);
  padding: 14px 16px 16px;
}

.page-about .track-rail__title {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.3em;
  color: var(--neon);
}

.page-about .track-rail__list {
  list-style: none;
  margin: 12px 0 0;
  padding: 0 0 4px;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

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

.page-about .track-rail__link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  white-space: nowrap;
  padding: 7px 12px;
  border: 1px solid var(--metal);
  color: var(--stand);
  font-size: 13px;
  text-decoration: none;
  transition: border-color 0.18s ease, color 0.18s ease, background-color 0.18s ease;
}

.page-about .track-rail__link:hover,
.page-about .track-rail__link:focus-visible {
  border-color: var(--neon);
  color: var(--neon);
}

.page-about .track-rail__idx {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--mist);
}

/* ---------- 章节 ---------- */

.page-about .stage {
  padding: 26px 0 30px;
}

.page-about .stage:first-child {
  padding-top: 4px;
}

.page-about .stage__head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 16px;
}

.page-about .stage__num {
  flex: none;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.2em;
  color: var(--neon);
}

.page-about .stage__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(21px, 3.6vw, 30px);
  line-height: 1.25;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .stage__body p {
  color: var(--stand);
  font-size: 16px;
  line-height: 1.78;
  margin: 0 0 14px;
  max-width: 66ch;
}

.page-about .stage__body .stage__body-pause {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--mist);
  border-left: 2px solid var(--neon);
  padding: 7px 0 7px 13px;
  margin: 20px 0 0;
  max-width: 60ch;
}

.page-about .stage__body .stage__body-after {
  margin-top: 18px;
  color: var(--paper);
}

/* ---------- 三个入口卡片 ---------- */

.page-about .line-list {
  display: grid;
  gap: 12px;
  margin: 20px 0 0;
}

.page-about .line-card {
  position: relative;
  background: var(--turf);
  border: var(--edge);
  box-shadow: var(--paper-shadow);
  padding: 18px 20px 20px;
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.page-about .line-card::before {
  content: "";
  position: absolute;
  left: 0;
  top: 18px;
  bottom: 18px;
  width: 2px;
  background: var(--neon);
  opacity: 0.5;
}

.page-about .line-card:hover {
  transform: translateY(-2px);
  border-color: var(--neon);
}

.page-about .line-card__name {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 18px;
  color: var(--paper);
}

.page-about .line-card__desc {
  margin: 0 0 14px;
  color: var(--stand);
  font-size: 15px;
  line-height: 1.75;
}

.page-about .line-card__tags {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.page-about .line-card__tags li {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--mist);
  border: 1px solid var(--metal);
  padding: 3px 8px;
}

/* ---------- 汇流图 ---------- */

.page-about .flow-figure {
  margin: 26px 0 0;
  border: var(--edge);
  background-color: var(--night);
  background-image: var(--turf-lines);
  padding: 14px 14px 10px;
  overflow: hidden;
}

.page-about .flow-figure svg {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .flow-line path {
  fill: none;
  stroke: var(--metal);
  stroke-width: 2;
  transition: stroke 0.2s ease;
}

.page-about .flow-line circle {
  fill: var(--night);
  stroke: var(--mist);
  stroke-width: 2;
  transition: stroke 0.2s ease, fill 0.2s ease;
}

.page-about .flow-line__label {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  fill: var(--mist);
  transition: fill 0.2s ease;
}

.page-about .flow-line:hover path,
.page-about .flow-line:focus-visible path {
  stroke: var(--neon);
}

.page-about .flow-line:hover circle,
.page-about .flow-line:focus-visible circle {
  fill: var(--neon);
  stroke: var(--neon);
}

.page-about .flow-line:hover .flow-line__label,
.page-about .flow-line:focus-visible .flow-line__label {
  fill: var(--paper);
}

.page-about .flow-line:focus {
  outline: none;
}

.page-about .flow-trunk {
  fill: none;
  stroke: var(--neon);
  stroke-width: 2;
}

.page-about .flow-node {
  fill: var(--neon);
  stroke: var(--night);
  stroke-width: 2;
}

.page-about .flow-out {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  fill: var(--neon);
}

/* ---------- 维护章节分栏 ---------- */

.page-about .stage__split {
  display: grid;
  gap: 20px;
}

.page-about .stage__split-main p {
  color: var(--stand);
  font-size: 16px;
  line-height: 1.78;
  margin: 0 0 14px;
  max-width: 64ch;
}

.page-about .maintain-figure {
  margin: 0;
}

.page-about .maintain-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.85) contrast(1.05);
}

/* ---------- 服务对象 ---------- */

.page-about .who-grid {
  display: grid;
  gap: 12px;
  margin-top: 20px;
}

.page-about .who-card {
  border: var(--edge);
  background-color: var(--turf);
  background-image: var(--turf-lines);
  padding: 16px 18px 18px;
  transition: border-color 0.2s ease;
}

.page-about .who-card:hover {
  border-color: var(--mist);
}

.page-about .who-card__role {
  margin: 0 0 9px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 16px;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .who-card__scene {
  margin: 0;
  color: var(--stand);
  font-size: 14.5px;
  line-height: 1.72;
}

/* ---------- 时间轨道 ---------- */

.page-about .track-banner {
  margin: 0 0 26px;
  border: var(--edge);
  overflow: hidden;
  background-color: var(--night);
  background-image: var(--turf-lines);
}

.page-about .track-banner img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.7) contrast(1.06);
}

.page-about .timeline {
  list-style: none;
  margin: 22px 0 0;
  padding: 0 0 0 26px;
  position: relative;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: linear-gradient(180deg, var(--neon) 0%, rgba(61, 242, 192, 0.14) 78%, rgba(61, 242, 192, 0) 100%);
}

.page-about .timeline__item {
  position: relative;
  padding: 0 0 26px;
}

.page-about .timeline__item:last-child {
  padding-bottom: 0;
}

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 5px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--night);
  border: 2px solid var(--neon);
  transition: background-color 0.22s ease;
}

.page-about .timeline__item:hover::before,
.page-about .timeline__item:focus-within::before {
  background: var(--neon);
}

.page-about .timeline__item.is-current::before {
  background: var(--neon);
  box-shadow: 0 0 0 4px rgba(61, 242, 192, 0.16);
}

.page-about .timeline__tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--neon);
  border: 1px solid rgba(61, 242, 192, 0.36);
  padding: 3px 8px;
  margin-bottom: 9px;
}

.page-about .timeline__item.is-current .timeline__tag {
  color: var(--night);
  background: var(--neon);
  border-color: var(--neon);
}

.page-about .timeline__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 18px;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .timeline__text {
  margin: 0;
  color: var(--stand);
  font-size: 15px;
  line-height: 1.75;
  max-width: 58ch;
}

/* ---------- 团队横幅 ---------- */

.page-about .team-banner {
  margin: 6px 0 0;
  border: var(--edge);
  overflow: hidden;
  background-color: var(--night);
  background-image: var(--turf-lines);
}

.page-about .team-banner img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.75) contrast(1.08);
}

/* ---------- 收束 ---------- */

.page-about .about-cta {
  margin: 24px 0 0;
  border: 1px solid rgba(61, 242, 192, 0.4);
  background-color: var(--turf);
  background-image: var(--turf-lines);
  padding: 20px 20px 22px;
}

.page-about .about-cta__text {
  margin: 0 0 16px;
  color: var(--paper);
  font-size: 16px;
  line-height: 1.72;
  max-width: 58ch;
}

.page-about .about-cta__links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

/* ---------- 渐进增强 ---------- */

.page-about.reveal-ready [data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.page-about.reveal-ready [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  .page-about.reveal-ready [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .page-about .line-card,
  .page-about .who-card,
  .page-about .timeline__item::before {
    transition: none;
  }

  .page-about .line-card:hover {
    transform: none;
  }
}

/* ---------- 响应式 ---------- */

@media (min-width: 640px) {
  .page-about .about-head__facts {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (min-width: 720px) {
  .page-about .line-list {
    grid-template-columns: repeat(6, 1fr);
  }

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

  .page-about .line-card:nth-child(2) {
    grid-column: span 2;
  }

  .page-about .line-card:nth-child(3) {
    grid-column: 2 / span 5;
  }

  .page-about .stage__split {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
    gap: 26px;
    align-items: start;
  }

  .page-about .who-grid {
    grid-template-columns: repeat(12, 1fr);
    gap: 12px;
  }

  .page-about .who-card:nth-child(1) {
    grid-column: span 7;
  }

  .page-about .who-card:nth-child(2) {
    grid-column: span 5;
  }

  .page-about .who-card:nth-child(3) {
    grid-column: span 5;
  }

  .page-about .who-card:nth-child(4) {
    grid-column: span 7;
  }
}

@media (min-width: 900px) {
  .page-about .about-shell {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: var(--about-gap);
    align-items: start;
  }

  .page-about .track-rail {
    position: sticky;
    top: calc(var(--bar-h) + 20px);
    padding: 16px 16px 18px;
  }

  .page-about .track-rail__list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    margin-top: 14px;
    padding: 0;
    border-left: 1px solid var(--metal);
  }

  .page-about .track-rail__item {
    flex: none;
  }

  .page-about .track-rail__link {
    display: flex;
    width: 100%;
    white-space: normal;
    border: 0;
    border-left: 2px solid transparent;
    margin-left: -1px;
    padding: 8px 10px;
    line-height: 1.5;
    font-size: 13.5px;
  }

  .page-about .track-rail__link:hover,
  .page-about .track-rail__link:focus-visible {
    border-left-color: var(--neon);
    background: rgba(61, 242, 192, 0.07);
  }

  .page-about .about-head {
    padding: 30px 0 42px;
  }

  .page-about .stage {
    padding: 34px 0 38px;
  }

  .page-about .timeline {
    padding-left: 32px;
  }

  .page-about .timeline__item {
    padding-bottom: 30px;
  }

  .page-about .timeline__item::before {
    left: -32px;
  }
}

@media (min-width: 1100px) {
  .page-about .stage__num {
    font-size: 15px;
  }
}
</PAGE_CSS>>>