.page-about {
  --ab-rail: 176px;
  --ab-line: rgba(195, 208, 216, 0.16);
  --ab-line-soft: rgba(195, 208, 216, 0.08);
  --ab-muted: var(--bys-steel);
  --ab-body: #c6d7e2;
  --ab-accent: var(--bys-amber);
  background: var(--bys-midnight);
  color: var(--bys-frost);
  font-family: var(--bys-font-body);
  overflow-x: clip;
}

.page-about .ab-hero {
  position: relative;
  padding: clamp(20px, 4vw, 40px) 0 clamp(32px, 5vw, 64px);
  background:
    radial-gradient(92% 72% at 84% 6%, rgba(20, 80, 122, 0.62) 0%, rgba(20, 80, 122, 0) 62%),
    linear-gradient(180deg, var(--bys-midnight) 0%, #04121d 100%);
  border-bottom: 1px solid var(--ab-line);
}

.page-about .ab-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: repeating-linear-gradient(180deg, rgba(234, 242, 247, 0.035) 0 1px, transparent 1px 4px);
  opacity: 0.6;
}

.page-about .ab-hero > * {
  position: relative;
  z-index: 1;
}

.page-about .bys-breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 clamp(18px, 3vw, 30px);
  font-size: 13px;
  color: var(--ab-muted);
}

.page-about .bys-breadcrumb .bys-breadcrumb__item {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.page-about .bys-breadcrumb .bys-breadcrumb__item + .bys-breadcrumb__item::before {
  content: "/";
  color: rgba(143, 166, 182, 0.6);
}

.page-about .bys-breadcrumb a {
  color: var(--bys-frost);
  text-decoration: none;
}

.page-about .bys-breadcrumb a:hover,
.page-about .bys-breadcrumb a:focus-visible {
  color: var(--bys-amber);
}

.page-about .ab-hero__grid {
  display: grid;
  gap: clamp(24px, 4vw, 44px);
}

.page-about .ab-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 14px;
  font-family: var(--bys-font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--bys-amber);
}

.page-about .ab-eyebrow::before {
  content: "";
  width: 28px;
  height: 2px;
  background: var(--bys-flare);
}

.page-about .ab-hero__title {
  display: flex;
  flex-direction: column;
  margin: 0 0 18px;
  font-family: var(--bys-font-display);
  font-weight: 900;
  font-size: clamp(2.35rem, 6.6vw, 4.5rem);
  line-height: 0.98;
  letter-spacing: -0.03em;
}

.page-about .ab-hero__title-mark {
  color: var(--bys-amber);
}

.page-about .ab-hero__deck {
  max-width: 50ch;
  margin: 0;
  font-size: clamp(0.95rem, 1.5vw, 1.06rem);
  line-height: 1.8;
  color: var(--ab-body);
}

.page-about .ab-hero__facts {
  display: flex;
  flex-wrap: wrap;
  gap: clamp(16px, 3vw, 38px);
  margin: 22px 0 0;
  padding: 16px 0;
  list-style: none;
  border-top: 1px solid var(--ab-line);
  border-bottom: 1px solid var(--ab-line);
}

.page-about .ab-hero__facts li {
  display: flex;
  flex-direction: column;
  gap: 4px;
  min-width: 0;
}

.page-about .ab-hero__num {
  font-family: var(--bys-font-mono);
  font-size: clamp(1.35rem, 2.4vw, 1.95rem);
  letter-spacing: 0.02em;
  color: var(--bys-frost);
}

.page-about .ab-hero__unit {
  margin-left: 2px;
  font-size: 0.6em;
  color: var(--bys-flare);
}

.page-about .ab-hero__cap {
  font-size: 12px;
  letter-spacing: 0.02em;
  color: var(--ab-muted);
}

.page-about .ab-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

.page-about .ab-fig {
  margin: 0;
  min-width: 0;
}

.page-about .ab-fig__img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  background: var(--bys-deep);
}

.page-about .ab-fig--hero .ab-fig__img {
  aspect-ratio: 14 / 9;
  clip-path: polygon(0 0, 100% 0, 100% 90%, 0 100%);
}

.page-about .ab-fig--archive .ab-fig__img {
  aspect-ratio: 10 / 8;
}

.page-about .ab-fig--map .ab-fig__img {
  aspect-ratio: 12 / 7;
}

.page-about .ab-fig__cap {
  margin-top: 10px;
  font-family: var(--bys-font-mono);
  font-size: 11px;
  line-height: 1.6;
  letter-spacing: 0.02em;
  color: var(--ab-muted);
}

.page-about .ab-board {
  display: grid;
  padding: clamp(16px, 3vw, 28px) 0 clamp(44px, 6vw, 84px);
}

.page-about .ab-years {
  min-width: 0;
}

.page-about .ab-years__label {
  margin: 0 0 10px;
  font-family: var(--bys-font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--ab-muted);
}

.page-about .ab-years__list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 6px;
  list-style: none;
  overflow-x: auto;
}

.page-about .ab-years__link {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 0;
  flex: 0 0 auto;
  padding: 10px 14px;
  border: 1px solid var(--ab-line);
  background: rgba(20, 80, 122, 0.18);
  color: var(--bys-frost);
  text-decoration: none;
  transition: border-color var(--bys-speed) var(--bys-ease), background-color var(--bys-speed) var(--bys-ease);
}

.page-about .ab-years__y {
  font-family: var(--bys-font-mono);
  font-size: 1.02rem;
  letter-spacing: 0.02em;
}

.page-about .ab-years__t {
  font-size: 12px;
  white-space: nowrap;
  color: var(--ab-muted);
}

.page-about .ab-years__link:hover,
.page-about .ab-years__link:focus-visible {
  border-color: var(--bys-flare);
  background: rgba(242, 106, 46, 0.14);
}

.page-about .ab-years__link:hover .ab-years__y,
.page-about .ab-years__link:focus-visible .ab-years__y {
  color: var(--bys-amber);
}

.page-about .ab-years__link--now {
  border-color: var(--bys-flare);
}

.page-about .ab-years__link--now .ab-years__y {
  color: var(--bys-amber);
}

.page-about .ab-chapters {
  min-width: 0;
}

.page-about .ab-chapter {
  padding: clamp(28px, 4.4vw, 60px) 0;
  border-top: 1px solid var(--ab-line);
}

.page-about .ab-chapter:first-child {
  border-top: 0;
}

.page-about .ab-chapter--paper {
  --ab-line: rgba(6, 23, 37, 0.14);
  --ab-muted: #4a6070;
  --ab-accent: var(--bys-flare);
  --ab-body: #22384a;
  margin: clamp(18px, 3vw, 32px) 0;
  padding: clamp(24px, 3.4vw, 46px) clamp(20px, 3vw, 42px);
  background: var(--bys-paper);
  color: var(--bys-midnight);
  border-top: 1px solid rgba(6, 23, 37, 0.12);
  box-shadow:
    0 10px 0 -5px #ded8c9,
    0 20px 0 -10px #cdc6b4;
}

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

.page-about .ab-chapter__num {
  flex: 0 0 auto;
  padding-top: 4px;
  font-family: var(--bys-font-mono);
  font-size: 13px;
  letter-spacing: 0.12em;
  color: var(--ab-accent);
}

.page-about .ab-chapter__title {
  margin: 0;
  font-family: var(--bys-font-display);
  font-weight: 900;
  font-size: clamp(1.45rem, 3.6vw, 2.5rem);
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.page-about .ab-summary {
  max-width: 64ch;
  margin: 0;
  font-size: clamp(0.94rem, 1.4vw, 1.04rem);
  line-height: 1.82;
  color: var(--ab-body);
}

.page-about .ab-summary + .ab-summary {
  margin-top: 14px;
}

.page-about .ab-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 22px 0 0;
}

.page-about .ab-stat {
  flex: 1 1 150px;
  min-width: 0;
  padding: 12px 14px;
  border: 1px solid var(--ab-line);
  background: rgba(20, 80, 122, 0.18);
}

.page-about .ab-chapter--paper .ab-stat {
  background: rgba(6, 23, 37, 0.04);
}

.page-about .ab-stat__num {
  display: block;
  font-family: var(--bys-font-mono);
  font-size: clamp(1.25rem, 2.2vw, 1.85rem);
  letter-spacing: 0.02em;
  color: var(--ab-accent);
}

.page-about .ab-stat__unit {
  margin-left: 2px;
  font-size: 0.6em;
}

.page-about .ab-stat__label {
  display: block;
  margin-top: 4px;
  font-size: 12px;
  line-height: 1.5;
  color: var(--ab-muted);
}

.page-about .ab-stat--fold .ab-stat__sum {
  display: block;
  list-style: none;
  cursor: pointer;
}

.page-about .ab-stat--fold .ab-stat__sum::-webkit-details-marker {
  display: none;
}

.page-about .ab-stat--fold .ab-stat__sum::after {
  content: "＋ 展开说明";
  display: block;
  margin-top: 6px;
  font-family: var(--bys-font-mono);
  font-size: 11px;
  letter-spacing: 0.04em;
  color: var(--ab-muted);
}

.page-about .ab-stat--fold[open] {
  border-color: var(--bys-flare);
}

.page-about .ab-stat--fold[open] .ab-stat__sum::after {
  content: "－ 收起说明";
}

.page-about .ab-stat__note {
  margin: 10px 0 0;
  font-size: 12px;
  line-height: 1.7;
  color: var(--ab-muted);
}

.page-about .ab-more {
  margin: 22px 0 0;
  font-size: 0.9rem;
  line-height: 1.7;
  color: var(--ab-muted);
}

.page-about .ab-more a {
  color: var(--ab-accent);
  text-decoration: none;
  border-bottom: 1px solid currentColor;
}

.page-about .ab-more a:hover,
.page-about .ab-more a:focus-visible {
  color: var(--bys-amber);
}

.page-about .ab-chapter--paper .ab-more a:hover,
.page-about .ab-chapter--paper .ab-more a:focus-visible {
  color: var(--bys-midnight);
}

.page-about .ab-timeline {
  display: grid;
  gap: 0;
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-timeline__item {
  display: grid;
  gap: 5px;
  padding: 16px 0;
  border-top: 1px dashed var(--ab-line);
}

.page-about .ab-timeline__time {
  font-family: var(--bys-font-mono);
  font-size: 0.84rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  line-height: 1.5;
  color: var(--ab-accent);
}

.page-about .ab-timeline__title {
  margin: 0 0 6px;
  font-size: 1rem;
  font-weight: 800;
  letter-spacing: -0.01em;
}

.page-about .ab-timeline__text {
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.75;
  color: var(--ab-muted);
}

.page-about .ab-split {
  display: grid;
  gap: clamp(18px, 3vw, 32px);
  margin-top: 20px;
}

.page-about .ab-split__main {
  min-width: 0;
}

.page-about .ab-miles {
  display: grid;
  gap: 14px;
  margin-top: 22px;
}

.page-about .ab-mile {
  padding: 18px;
  border: 1px solid var(--ab-line);
  background: rgba(6, 23, 37, 0.04);
}

.page-about .ab-mile--now {
  border-color: var(--bys-flare);
  box-shadow: inset 0 3px 0 var(--bys-flare);
}

.page-about .ab-mile__year {
  display: block;
  font-family: var(--bys-font-mono);
  font-size: 1.55rem;
  letter-spacing: 0.02em;
  color: var(--bys-flare);
}

.page-about .ab-mile__name {
  margin: 6px 0 8px;
  font-size: 1.02rem;
  font-weight: 800;
  letter-spacing: -0.01em;
}

.page-about .ab-mile__text {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.72;
  color: var(--ab-muted);
}

.page-about .ab-eco {
  display: grid;
  gap: 12px;
  margin-top: 24px;
}

.page-about .ab-eco__card {
  padding: 16px;
  border: 1px solid var(--ab-line);
  background: rgba(20, 80, 122, 0.18);
  transition: border-color var(--bys-speed) var(--bys-ease), transform var(--bys-speed) var(--bys-ease);
}

.page-about .ab-eco__card:hover,
.page-about .ab-eco__card:focus-within {
  border-color: var(--bys-flare);
  transform: translateY(-2px);
}

.page-about .ab-eco__name {
  margin: 0 0 8px;
  font-size: 1rem;
  font-weight: 800;
  letter-spacing: -0.01em;
}

.page-about .ab-eco__desc {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.72;
  color: var(--ab-muted);
}

.page-about .ab-eco__tag {
  margin: 12px 0 0;
  font-family: var(--bys-font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--bys-flare);
}

.page-about .ab-cta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px;
  margin-top: 24px;
}

.page-about .ab-cta__link {
  font-size: 0.92rem;
  color: var(--bys-midnight);
  text-decoration: none;
  border-bottom: 2px solid var(--bys-flare);
  padding-bottom: 2px;
}

.page-about .ab-cta__link:hover,
.page-about .ab-cta__link:focus-visible {
  color: var(--bys-flare);
}

.page-about a:focus-visible,
.page-about summary:focus-visible,
.page-about .ab-eco__card:focus-visible {
  outline: 2px solid var(--bys-amber);
  outline-offset: 3px;
}

@media (min-width: 720px) {
  .page-about .ab-timeline__item {
    grid-template-columns: 150px minmax(0, 1fr);
    gap: 20px;
    align-items: start;
  }

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

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

@media (min-width: 860px) {
  .page-about .ab-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: end;
  }

  .page-about .ab-split {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: start;
  }
}

@media (min-width: 1000px) {
  .page-about .ab-board {
    grid-template-columns: var(--ab-rail) minmax(0, 1fr);
    column-gap: clamp(28px, 4vw, 56px);
  }

  .page-about .ab-years {
    position: sticky;
    top: 108px;
    align-self: start;
    padding-bottom: 24px;
  }

  .page-about .ab-years__list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding: 0;
    border-left: 1px solid var(--ab-line);
  }

  .page-about .ab-years__link {
    flex-direction: row;
    align-items: baseline;
    justify-content: space-between;
    gap: 10px;
    margin-left: -1px;
    padding: 10px 0 10px 14px;
    border: 0;
    border-left: 2px solid transparent;
    background: none;
  }

  .page-about .ab-years__link:hover,
  .page-about .ab-years__link:focus-visible {
    background: linear-gradient(90deg, rgba(242, 106, 46, 0.16), rgba(242, 106, 46, 0));
  }

  .page-about .ab-years__link:hover,
  .page-about .ab-years__link:focus-visible,
  .page-about .ab-years__link--now {
    border-left-color: var(--bys-flare);
  }

  .page-about .ab-years__t {
    font-size: 11px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-eco__card,
  .page-about .ab-years__link {
    transition: none;
  }

  .page-about .ab-eco__card:hover {
    transform: none;
  }
}
<<<END>>>