.page-about {
  --ab-gap: clamp(16px, 2.2vw, 28px);
  background: var(--c-deep);
  color: var(--c-paper);
  overflow-x: hidden;
  padding-bottom: clamp(56px, 8vw, 110px);
}

/* ---------- 面包屑 ---------- */
.page-about .ab-crumbs {
  padding-top: clamp(18px, 3vw, 32px);
}

.page-about .ab-crumbs .crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  letter-spacing: 0.02em;
  color: var(--c-mist);
}

.page-about .ab-crumbs a {
  color: var(--c-mist);
  text-decoration: none;
  transition: color 200ms var(--ease);
}

.page-about .ab-crumbs a:hover {
  color: var(--c-orange);
}

.page-about .ab-crumbs [aria-current="page"] {
  color: var(--c-paper);
  font-weight: 600;
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  display: grid;
  gap: clamp(30px, 4.5vw, 60px);
  align-items: center;
  padding-top: clamp(22px, 3.6vw, 46px);
  padding-bottom: clamp(46px, 7vw, 92px);
}

.page-about .ab-hero-copy .eyebrow {
  color: var(--c-orange);
}

.page-about .ab-hero h1 {
  margin: 14px 0 0;
  padding-inline: 4px;
  font-family: var(--f-head);
  font-weight: 900;
  font-size: clamp(31px, 4.4vw + 14px, 66px);
  line-height: 1.07;
  letter-spacing: -0.02em;
  color: var(--c-paper);
  transform: skewX(-6deg);
  transform-origin: left bottom;
}

.page-about .ab-lede {
  margin: 22px 0 0;
  max-width: 60ch;
  font-size: clamp(15.5px, 0.9vw + 12px, 18px);
  line-height: 1.85;
  color: var(--c-mist);
}

.page-about .ab-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(24px, 3vw, 34px);
}

.page-about .ab-hero-visual {
  position: relative;
  border-radius: var(--r-lg);
  border: 1px solid var(--c-track);
  background:
    radial-gradient(130% 110% at 85% 0%, rgba(255, 107, 26, 0.18), transparent 58%),
    linear-gradient(165deg, var(--c-panel) 0%, var(--c-night) 78%);
  padding: clamp(20px, 2.8vw, 32px);
  overflow: hidden;
}

.page-about .ab-arc {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .ab-hero-stat {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px;
  margin-top: clamp(8px, 1.4vw, 16px);
  padding-top: clamp(14px, 2vw, 22px);
  border-top: 1px solid var(--c-track);
}

.page-about .ab-hero-num {
  font-family: var(--f-num);
  font-weight: 600;
  font-size: clamp(46px, 6.4vw, 74px);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--c-orange);
}

.page-about .ab-hero-unit {
  font-size: 14px;
  line-height: 1.6;
  color: var(--c-mist);
}

.page-about .ab-hero-mini {
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .ab-hero-mini li {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 10px 0;
  font-size: 14px;
  color: var(--c-mist);
  border-bottom: 1px dashed rgba(27, 54, 103, 0.9);
}

.page-about .ab-hero-mini li:last-child {
  border-bottom: 0;
}

.page-about .ab-hero-mini .num {
  font-family: var(--f-num);
  font-weight: 600;
  font-size: 17px;
  color: var(--c-paper);
  min-width: 4.5ch;
}

/* ---------- 起点 ---------- */
.page-about .ab-origin-prose {
  margin-top: clamp(18px, 2.6vw, 28px);
  color: var(--c-mist);
}

.page-about .ab-origin-facts {
  list-style: none;
  margin: clamp(26px, 3.8vw, 42px) 0 0;
  padding: 0;
  display: grid;
  gap: var(--ab-gap);
}

.page-about .ab-origin-facts li {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: clamp(18px, 2.4vw, 26px);
  border-radius: var(--r-md);
  border: 1px solid var(--c-track);
  background: linear-gradient(160deg, rgba(16, 34, 74, 0.9), rgba(10, 23, 48, 0.9));
}

.page-about .ab-origin-facts .num {
  font-family: var(--f-num);
  font-weight: 600;
  font-size: clamp(30px, 3.6vw, 42px);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--c-gold);
}

.page-about .ab-origin-facts span:last-child {
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--c-mist);
}

/* ---------- 时间轴 ---------- */
.page-about .ab-tl {
  position: relative;
  isolation: isolate;
  overflow: hidden;
}

.page-about .ab-tl-bg {
  position: absolute;
  inset: 0;
  z-index: -3;
}

.page-about .ab-tl-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.16;
}

.page-about .ab-tl::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -2;
  background: linear-gradient(180deg, var(--c-deep) 0%, rgba(5, 13, 31, 0.86) 44%, var(--c-deep) 100%);
  pointer-events: none;
}

.page-about .ab-tl-mark {
  position: absolute;
  top: clamp(14px, 3vw, 36px);
  right: -0.04em;
  z-index: -1;
  display: flex;
  align-items: baseline;
  gap: 0.06em;
  font-family: var(--f-num);
  font-weight: 600;
  font-size: clamp(76px, 17vw, 190px);
  line-height: 0.82;
  letter-spacing: -0.05em;
  color: var(--c-track);
  opacity: 0.3;
  pointer-events: none;
  user-select: none;
}

.page-about .ab-tl-mark em {
  font-style: normal;
  font-size: 0.5em;
  color: var(--c-signal);
}

.page-about .ab-tl-inner {
  position: relative;
  z-index: 1;
}

.page-about .ab-tl-head .prose {
  color: var(--c-mist);
  max-width: 62ch;
}

.page-about .ab-tl-list {
  --ab-tl-gap: clamp(38px, 6.2vw, 82px);
  list-style: none;
  margin: clamp(34px, 5vw, 60px) 0 0;
  padding: 0;
  display: grid;
  gap: var(--ab-tl-gap);
  max-width: 920px;
}

.page-about .ab-tl-item {
  position: relative;
  padding-left: 34px;
}

.page-about .ab-tl-item::after {
  content: "";
  position: absolute;
  left: 8px;
  top: 26px;
  bottom: calc(-1 * var(--ab-tl-gap));
  width: 1px;
  background: linear-gradient(180deg, var(--c-track) 0%, rgba(27, 54, 103, 0.1) 100%);
}

.page-about .ab-tl-item:last-child::after {
  display: none;
}

.page-about .ab-tl-dot {
  position: absolute;
  left: 1px;
  top: 6px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--c-track);
  box-shadow: 0 0 0 4px rgba(5, 13, 31, 0.92);
  transition: background 320ms var(--ease), box-shadow 320ms var(--ease), transform 320ms var(--ease);
}

.page-about .ab-tl-item.is-in .ab-tl-dot {
  background: var(--c-orange);
  box-shadow: 0 0 0 4px rgba(255, 107, 26, 0.16), 0 0 18px rgba(255, 107, 26, 0.45);
  transform: scale(1.08);
}

.page-about .ab-tl-stage {
  margin: 0;
  font-size: 12.5px;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--c-teal);
}

.page-about .ab-tl-stage .num {
  font-family: var(--f-num);
  font-size: 15px;
  letter-spacing: 0;
  color: var(--c-gold);
}

.page-about .ab-tl-item h3 {
  margin: 8px 0 0;
  font-family: var(--f-head);
  font-weight: 800;
  font-size: clamp(19px, 1.8vw + 9px, 28px);
  line-height: 1.3;
  color: var(--c-paper);
}

.page-about .ab-tl-text {
  margin: 12px 0 0;
  max-width: 58ch;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--c-mist);
}

.page-about .ab-tl-cover {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  margin: 16px 0 0;
  padding: 7px 16px;
  border-radius: var(--r-pill);
  border: 1px solid var(--c-track);
  background: rgba(16, 34, 74, 0.72);
  font-size: 13px;
  color: var(--c-mist);
}

.page-about .ab-tl-cover .num {
  font-family: var(--f-num);
  font-weight: 600;
  font-size: 16px;
  color: var(--c-paper);
}

/* ---------- 团队 ---------- */
.page-about .ab-team-grid {
  display: grid;
  gap: clamp(28px, 4vw, 54px);
  align-items: start;
}

.page-about .ab-team-figure {
  margin: 0;
  border-radius: var(--r-lg);
  border: 1px solid var(--c-track);
  background: var(--c-night);
  overflow: hidden;
}

.page-about .ab-team-figure img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.page-about .ab-team-figure figcaption {
  padding: 12px 18px 16px;
  border-top: 1px solid var(--c-track);
  font-size: 12.5px;
  line-height: 1.65;
  color: var(--c-mist);
}

.page-about .ab-team-copy .eyebrow {
  color: var(--c-orange);
}

.page-about .ab-team-copy h2 {
  margin: 12px 0 0;
  font-family: var(--f-head);
  font-weight: 900;
  font-size: clamp(26px, 2.6vw + 12px, 44px);
  line-height: 1.18;
  letter-spacing: -0.02em;
  color: var(--c-paper);
}

.page-about .ab-team-lead {
  margin: 18px 0 0;
  max-width: 64ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--c-mist);
}

.page-about .ab-ring {
  display: grid;
  gap: clamp(20px, 3vw, 32px);
  align-items: center;
  margin-top: clamp(26px, 3.4vw, 38px);
}

.page-about .ab-ring-svg {
  display: block;
  width: 100%;
  max-width: 200px;
  height: auto;
}

.page-about .ab-ring-track {
  stroke: var(--c-track);
  opacity: 0.5;
}

.page-about .ab-ring-seg {
  transition: stroke-width 260ms var(--ease), opacity 260ms var(--ease);
}

.page-about .ab-ring-seg--data { stroke: var(--c-orange); }
.page-about .ab-ring-seg--edit { stroke: var(--c-signal); }
.page-about .ab-ring-seg--vis { stroke: var(--c-teal); }
.page-about .ab-ring-seg--ops { stroke: var(--c-gold); }

.page-about .ab-ring:has(.ab-legend-item:nth-child(1):hover) .ab-ring-seg--data,
.page-about .ab-ring:has(.ab-legend-item:nth-child(2):hover) .ab-ring-seg--edit,
.page-about .ab-ring:has(.ab-legend-item:nth-child(3):hover) .ab-ring-seg--vis,
.page-about .ab-ring:has(.ab-legend-item:nth-child(4):hover) .ab-ring-seg--ops {
  stroke-width: 22;
}

.page-about .ab-legend {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
}

.page-about .ab-legend-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  border-radius: var(--r-md);
  font-size: 14.5px;
  color: var(--c-mist);
  transition: background 220ms var(--ease), color 220ms var(--ease);
}

.page-about .ab-legend-item:hover {
  background: rgba(16, 34, 74, 0.85);
  color: var(--c-paper);
}

.page-about .ab-legend-item .num {
  margin-left: auto;
  font-family: var(--f-num);
  font-weight: 600;
  font-size: 17px;
  color: var(--c-paper);
}

.page-about .ab-swatch {
  width: 10px;
  height: 10px;
  border-radius: 3px;
  flex: none;
}

.page-about .ab-swatch--data { background: var(--c-orange); }
.page-about .ab-swatch--edit { background: var(--c-signal); }
.page-about .ab-swatch--vis { background: var(--c-teal); }
.page-about .ab-swatch--ops { background: var(--c-gold); }

.page-about .ab-team-note {
  margin: 22px 0 0;
  max-width: 64ch;
  font-size: 15px;
  line-height: 1.85;
  color: var(--c-mist);
  padding-left: 16px;
  border-left: 2px solid var(--c-track);
}

/* ---------- 数据流程 ---------- */
.page-about .ab-flow .section-head .prose {
  color: var(--c-mist);
}

.page-about .ab-steps {
  list-style: none;
  margin: clamp(30px, 4.6vw, 54px) 0 0;
  padding: 0;
  display: grid;
  gap: var(--ab-gap);
}

.page-about .ab-step {
  position: relative;
  padding: clamp(22px, 3vw, 30px);
  border-radius: var(--r-md);
  border: 1px solid var(--c-track);
  background: linear-gradient(165deg, rgba(16, 34, 74, 0.92), rgba(10, 23, 48, 0.92));
  transition: border-color 260ms var(--ease), transform 260ms var(--ease);
}

.page-about .ab-step:hover {
  border-color: var(--c-orange);
  transform: translateY(-3px);
}

.page-about .ab-step-no {
  display: block;
  margin-bottom: 14px;
  font-family: var(--f-num);
  font-weight: 600;
  font-size: 38px;
  line-height: 1;
  letter-spacing: -0.04em;
  color: var(--c-orange);
  opacity: 0.9;
}

.page-about .ab-step h3 {
  margin: 0;
  font-family: var(--f-head);
  font-weight: 800;
  font-size: clamp(18px, 1.4vw + 10px, 22px);
  line-height: 1.35;
  color: var(--c-paper);
}

.page-about .ab-step p {
  margin: 10px 0 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--c-mist);
}

.page-about .ab-sla {
  list-style: none;
  margin: clamp(28px, 4vw, 44px) 0 0;
  padding: 0;
  display: grid;
  gap: var(--ab-gap);
}

.page-about .ab-sla-card {
  padding: clamp(20px, 2.6vw, 28px);
  border-radius: var(--r-md);
}

.page-about .ab-sla-card .num {
  display: block;
  font-family: var(--f-num);
  font-weight: 600;
  font-size: clamp(34px, 4.2vw, 48px);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--c-orange);
}

.page-about .ab-sla-card p {
  margin: 12px 0 0;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--c-mist);
}

/* ---------- 城市与看台 ---------- */
.page-about .ab-city {
  position: relative;
  overflow: hidden;
}

.page-about .ab-skyline {
  display: block;
  width: 100%;
  height: clamp(58px, 9vw, 110px);
  margin-bottom: clamp(24px, 3.6vw, 42px);
  color: var(--c-track);
  opacity: 0.8;
}

.page-about .ab-skyline-arc {
  stroke: var(--c-orange);
  opacity: 0.55;
}

.page-about .ab-city-grid {
  display: grid;
  gap: clamp(26px, 3.6vw, 48px);
  align-items: start;
}

.page-about .ab-city-copy .eyebrow {
  color: var(--c-teal);
}

.page-about .ab-city-copy h2 {
  margin: 12px 0 0;
  font-family: var(--f-head);
  font-weight: 900;
  font-size: clamp(26px, 2.6vw + 12px, 44px);
  line-height: 1.18;
  letter-spacing: -0.02em;
  color: var(--c-paper);
}

.page-about .ab-city-copy p {
  margin: 18px 0 0;
  max-width: 62ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--c-mist);
}

.page-about .ab-city-copy .btn {
  margin-top: clamp(22px, 3vw, 30px);
}

.page-about .ab-city-facts {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: var(--ab-gap);
}

.page-about .ab-city-facts li {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 16px 20px;
  border-radius: var(--r-md);
  border: 1px solid var(--c-track);
  background: rgba(16, 34, 74, 0.6);
}

.page-about .ab-city-facts .num {
  flex: none;
  font-family: var(--f-num);
  font-weight: 600;
  font-size: clamp(20px, 1.6vw + 14px, 28px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--c-gold);
}

.page-about .ab-city-facts span:last-child {
  font-size: 14px;
  line-height: 1.6;
  color: var(--c-mist);
}

/* ---------- 收束 ---------- */
.page-about .ab-final-grid {
  display: grid;
  gap: clamp(28px, 4vw, 54px);
  align-items: start;
}

.page-about .ab-final-copy .eyebrow {
  color: var(--c-orange);
}

.page-about .ab-final-copy h2 {
  margin: 12px 0 0;
  font-family: var(--f-head);
  font-weight: 900;
  font-size: clamp(26px, 2.8vw + 12px, 46px);
  line-height: 1.16;
  letter-spacing: -0.02em;
  color: var(--c-paper);
}

.page-about .ab-final-copy p {
  margin: 18px 0 0;
  max-width: 62ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--c-mist);
}

.page-about .ab-final-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(24px, 3vw, 34px);
}

.page-about .ab-final-figure {
  margin: 0;
  border-radius: var(--r-lg);
  border: 1px solid var(--c-track);
  overflow: hidden;
  background: var(--c-night);
}

.page-about .ab-final-figure img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.page-about .ab-final-stats {
  list-style: none;
  margin: clamp(32px, 4.6vw, 54px) 0 0;
  padding: 0;
  display: grid;
  gap: var(--ab-gap);
}

.page-about .ab-final-stats li {
  padding: clamp(18px, 2.4vw, 26px);
  border-radius: var(--r-md);
}

.page-about .ab-final-stats .num {
  display: block;
  font-family: var(--f-num);
  font-weight: 600;
  font-size: clamp(28px, 3.2vw, 40px);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--c-paper);
}

.page-about .ab-final-stats p {
  margin: 10px 0 0;
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--c-mist);
}

/* ---------- 响应式 ---------- */
@media (min-width: 560px) {
  .page-about .ab-origin-facts {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .ab-ring {
    grid-template-columns: 190px minmax(0, 1fr);
  }
}

@media (min-width: 760px) {
  .page-about .ab-steps {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

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

@media (min-width: 960px) {
  .page-about .ab-hero {
    grid-template-columns: 7fr 5fr;
  }

  .page-about .ab-team-grid {
    grid-template-columns: 5fr 7fr;
  }

  .page-about .ab-city-grid {
    grid-template-columns: 7fr 5fr;
  }

  .page-about .ab-final-grid {
    grid-template-columns: 7fr 5fr;
  }

  .page-about .ab-tl-item {
    padding-left: 44px;
  }

  .page-about .ab-tl-item::after {
    left: 9px;
  }

  .page-about .ab-tl-dot {
    left: 1px;
    width: 18px;
    height: 18px;
  }

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

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-tl-dot,
  .page-about .ab-step,
  .page-about .ab-ring-seg,
  .page-about .ab-legend-item {
    transition: none;
  }

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