.page-about {
  background: var(--ink);
  color: var(--snow);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-top: clamp(24px, 5vw, 56px);
  position: relative;
}

.page-about .breadcrumbs {
  margin-bottom: clamp(18px, 3vw, 30px);
}

.page-about .about-h1 {
  font-family: var(--font-display);
  text-transform: uppercase;
  letter-spacing: .04em;
  line-height: .96;
  font-size: clamp(38px, 9vw, 88px);
  margin: 10px 0 clamp(20px, 4vw, 36px);
  max-width: 16em;
}

.page-about .h1-em {
  color: var(--cyan);
  text-transform: none;
  letter-spacing: .01em;
  font-size: .78em;
  display: inline-block;
  padding-bottom: .06em;
  border-bottom: 3px solid var(--pulse-edge);
}

.page-about .about-hero-grid {
  display: grid;
  gap: clamp(20px, 4vw, 36px);
}

.page-about .about-lede {
  max-width: 34em;
  margin: 0;
}

.page-about .hero-facts {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 2px;
  border-radius: var(--r-m);
  overflow: hidden;
  background: var(--raise);
}

.page-about .hero-fact {
  background: var(--panel);
  padding: 14px 18px;
  display: flex;
  align-items: baseline;
  gap: 14px;
}

.page-about .fact-num {
  font-size: 30px;
  line-height: 1;
  color: var(--cyan);
  flex: 0 0 auto;
}

.page-about .hero-fact:first-child .fact-num {
  color: var(--pulse);
}

.page-about .fact-label {
  font-size: 14px;
  color: var(--mist);
  line-height: 1.5;
}

.page-about .about-hero-figure {
  margin: clamp(28px, 5vw, 52px) 0 0;
  border-radius: 0;
}

.page-about .about-hero-figure img {
  width: 100%;
  height: auto;
}

/* ---------- 通用排版微调 ---------- */
.page-about .display-l {
  font-family: var(--font-display);
  text-transform: uppercase;
  letter-spacing: .03em;
  line-height: 1.06;
  font-size: clamp(26px, 5.4vw, 42px);
  margin: 8px 0 18px;
  color: var(--snow);
}

.page-about .origin-copy p,
.page-about .partner-copy p,
.page-about .cta-copy p {
  max-width: 34em;
  color: var(--snow);
  line-height: 1.8;
  margin: 0 0 16px;
}

.page-about .panel-title {
  font-family: var(--font-display);
  text-transform: uppercase;
  letter-spacing: .06em;
  font-size: 20px;
  margin: 0 0 16px;
  color: var(--snow);
}

/* ---------- 起点 ---------- */
.page-about .origin-grid {
  align-items: start;
}

.page-about .origin-panel {
  padding: 24px 22px;
  border-radius: var(--r-l);
}

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

.page-about .origin-list li {
  display: grid;
  grid-template-columns: 34px 1fr;
  gap: 12px;
  align-items: start;
  padding-top: 14px;
  border-top: 1px solid rgba(230, 245, 248, .16);
}

.page-about .origin-list li:first-child {
  border-top: 0;
  padding-top: 0;
}

.page-about .origin-idx {
  font-size: 13px;
  color: var(--cyan);
  letter-spacing: .1em;
  padding-top: 3px;
}

.page-about .origin-list p {
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--snow);
}

/* ---------- 团队带 ---------- */
.page-about .team-head {
  max-width: 40em;
  margin-bottom: clamp(20px, 4vw, 34px);
}

.page-about .team-note {
  color: var(--mist);
  line-height: 1.75;
  margin: 0;
  max-width: 34em;
}

.page-about .band {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2px;
  border-radius: var(--r-m);
  overflow: hidden;
  background: var(--raise);
}

.page-about .band-item {
  background: var(--panel);
  padding: 20px 20px 22px;
  border-left: 4px solid var(--raise);
  transition: background .16s var(--ease), border-color .16s var(--ease);
  outline: none;
}

.page-about .band-item--eng { border-left-color: var(--cyan); }
.page-about .band-item--fe { border-left-color: var(--indigo); }
.page-about .band-item--content { border-left-color: var(--pulse); }
.page-about .band-item--support { border-left-color: var(--amber); }

.page-about .band-item:hover,
.page-about .band-item:focus-visible {
  background: var(--raise);
}

.page-about .band-item:focus-visible {
  box-shadow: inset 0 0 0 2px var(--cyan);
}

.page-about .band-num {
  display: block;
  font-size: clamp(34px, 7vw, 46px);
  line-height: 1;
  color: var(--snow);
  letter-spacing: .02em;
}

.page-about .band-name {
  font-family: var(--font-display);
  text-transform: uppercase;
  letter-spacing: .05em;
  font-size: 18px;
  margin: 8px 0 10px;
  color: var(--cyan);
}

.page-about .band-desc {
  font-size: 14px;
  line-height: 1.72;
  color: var(--mist);
  margin: 0;
  max-width: 30em;
}

/* ---------- 链路 ---------- */
.page-about .flow-head {
  max-width: 42em;
  margin-bottom: clamp(22px, 4vw, 38px);
}

.page-about .flow-head .lede {
  margin: 0;
  max-width: 34em;
}

.page-about .flow-body {
  align-items: start;
}

.page-about .tree-scroll {
  overflow-x: auto;
  overflow-y: hidden;
  padding-bottom: 6px;
  border-radius: var(--r-m);
  background: radial-gradient(120% 100% at 12% 0%, rgba(0, 229, 208, .10), transparent 60%), var(--panel);
}

.page-about .tree-svg {
  display: block;
  width: 100%;
  min-width: 680px;
  height: auto;
}

.page-about .tree-path {
  fill: none;
  stroke: var(--cyan-edge);
  stroke-width: 2;
  stroke-dasharray: 6 7;
}

.page-about .tree-node {
  outline: none;
  cursor: default;
}

.page-about .tree-node .node-ring {
  fill: #0F151A;
  stroke: var(--raise);
  stroke-width: 3;
  transition: stroke .18s var(--ease), fill .18s var(--ease);
}

.page-about .node-idx {
  font-family: var(--font-mono);
  font-size: 16px;
  fill: var(--mist);
  text-anchor: middle;
  transition: fill .18s var(--ease);
}

.page-about .node-label {
  font-family: var(--font-display);
  font-size: 20px;
  letter-spacing: .08em;
  fill: var(--snow);
  text-anchor: middle;
}

.page-about .node-sub {
  font-size: 13px;
  fill: var(--mist);
  text-anchor: middle;
}

.page-about .tree-node:hover .node-ring,
.page-about .tree-node:focus-visible .node-ring {
  stroke: var(--cyan);
  fill: #062220;
}

.page-about .tree-node:hover .node-idx,
.page-about .tree-node:focus-visible .node-idx {
  fill: var(--cyan);
}

.page-about .tree-node:focus-visible .node-ring {
  stroke-width: 4;
}

.page-about .tree-steps {
  list-style: none;
  margin: 20px 0 0;
  padding: 0;
  display: grid;
  gap: 2px;
  background: var(--raise);
  border-radius: var(--r-m);
  overflow: hidden;
}

.page-about .step {
  background: var(--panel);
  padding: 16px 18px;
  display: grid;
  grid-template-columns: 32px 1fr;
  gap: 12px;
  align-items: start;
  transition: background .16s var(--ease);
}

.page-about .step:hover {
  background: var(--raise);
}

.page-about .step-idx {
  font-size: 12px;
  color: var(--cyan);
  letter-spacing: .1em;
  padding-top: 4px;
}

.page-about .step h3 {
  font-size: 16px;
  margin: 0 0 4px;
  color: var(--snow);
  letter-spacing: .02em;
}

.page-about .step p {
  margin: 0;
  font-size: 14px;
  line-height: 1.72;
  color: var(--mist);
}

.page-about .flow-figure {
  margin: 24px 0 0;
}

.page-about .flow-figure img {
  width: 100%;
  height: auto;
}

/* ---------- 时间轴 ---------- */
.page-about .tl-head {
  max-width: 44em;
  margin-bottom: clamp(22px, 4vw, 40px);
}

.page-about .tl-head .lede {
  margin: 0;
  max-width: 32em;
}

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

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 6px;
  bottom: 26px;
  width: 2px;
  background: linear-gradient(180deg, var(--cyan) 0%, rgba(0, 229, 208, .28) 55%, rgba(0, 229, 208, 0) 100%);
}

.page-about .tl-item {
  position: relative;
  padding-bottom: 22px;
  display: grid;
  gap: 12px;
}

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: -25px;
  top: 6px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--ink);
  border: 2px solid var(--cyan);
  box-shadow: 0 0 0 4px rgba(0, 229, 208, .12);
}

.page-about .tl-item--current::before {
  background: var(--pulse);
  border-color: var(--pulse);
  box-shadow: 0 0 0 5px rgba(255, 75, 31, .18);
}

.page-about .tl-year {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 18px;
  letter-spacing: .1em;
  color: var(--ink);
  background: var(--cyan);
  padding: 5px 30px 5px 12px;
  clip-path: polygon(0 0, 100% 0, 86% 100%, 0 100%);
}

.page-about .tl-item:nth-child(even) .tl-year {
  background: var(--wine);
  color: var(--snow);
}

.page-about .tl-item--current .tl-year {
  background: var(--pulse);
  color: var(--ink);
}

.page-about .tl-card {
  padding: 20px 20px 18px;
  border-radius: var(--r-m);
  border: 1px solid var(--hair);
  transition: border-color .16s var(--ease), transform .16s var(--ease);
}

.page-about .tl-card:hover {
  border-color: var(--cyan-edge);
  transform: translateY(-2px);
}

.page-about .tl-card h3 {
  font-family: var(--font-display);
  font-size: 21px;
  letter-spacing: .04em;
  margin: 0 0 8px;
  color: var(--snow);
}

.page-about .tl-card > p {
  margin: 0 0 12px;
  font-size: 15px;
  line-height: 1.78;
  color: var(--snow);
  max-width: 34em;
}

.page-about .tl-card details {
  border-top: 1px solid var(--hair);
  padding-top: 10px;
}

.page-about .tl-card summary {
  cursor: pointer;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .06em;
  color: var(--cyan);
  display: flex;
  align-items: center;
  gap: 8px;
  outline: none;
}

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

.page-about .tl-card summary::after {
  content: "+";
  font-size: 16px;
  line-height: 1;
  transition: transform .18s var(--ease);
}

.page-about .tl-card details[open] summary::after {
  transform: rotate(45deg);
}

.page-about .tl-card summary:focus-visible {
  box-shadow: 0 0 0 2px var(--cyan);
  border-radius: var(--r-s);
}

.page-about .tl-card details p {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.76;
  color: var(--mist);
  max-width: 34em;
}

.page-about .tl-figure {
  margin: clamp(24px, 4vw, 40px) 0 0;
}

.page-about .tl-figure img {
  width: 100%;
  height: auto;
}

/* ---------- 内容系列 ---------- */
.page-about .series-head {
  max-width: 42em;
  margin-bottom: clamp(20px, 4vw, 32px);
}

.page-about .series-note {
  color: var(--mist);
  line-height: 1.75;
  margin: 0;
  max-width: 34em;
}

.page-about .series-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2px;
  background: var(--raise);
  border-radius: var(--r-m);
  overflow: hidden;
}

.page-about .series-card {
  background: var(--panel);
  padding: 22px 20px;
  transition: background .16s var(--ease);
}

.page-about .series-card:hover {
  background: var(--raise);
}

.page-about .series-card .chip {
  margin-bottom: 12px;
}

.page-about .series-card h3 {
  font-family: var(--font-display);
  font-size: 19px;
  letter-spacing: .05em;
  margin: 0 0 8px;
  color: var(--snow);
}

.page-about .series-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.74;
  color: var(--mist);
}

/* ---------- 数据来源 ---------- */
.page-about .partner-grid {
  align-items: stretch;
}

.page-about .partner-figure {
  padding: 26px 24px;
  border-radius: var(--r-l);
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.page-about .partner-kicker {
  font-size: clamp(56px, 12vw, 88px);
  line-height: 1;
  color: var(--cyan);
  margin: 0;
}

.page-about .partner-kicker-label {
  font-family: var(--font-display);
  text-transform: uppercase;
  letter-spacing: .08em;
  font-size: 17px;
  color: var(--snow);
  margin: 6px 0 18px;
}

.page-about .partner-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .partner-list li {
  font-size: 14px;
  line-height: 1.6;
  color: var(--snow);
  padding-left: 16px;
  position: relative;
}

.page-about .partner-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .62em;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--pulse);
}

.page-about .partner-copy .partner-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 22px 0 0;
}

/* ---------- 收尾 ---------- */
.page-about .cta-block {
  padding: clamp(26px, 5vw, 44px);
  border-radius: var(--r-l);
  display: grid;
  gap: 22px;
}

.page-about .cta-copy h2 {
  margin-top: 0;
}

.page-about .cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
}

.page-about .cta-text-link {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .06em;
  color: var(--mist);
  text-decoration: underline;
  text-underline-offset: 4px;
}

.page-about .cta-text-link:hover {
  color: var(--cyan);
}

/* ---------- 断点 ---------- */
@media (min-width: 560px) {
  .page-about .series-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .page-about .hero-facts {
    grid-template-columns: repeat(3, 1fr);
  }
  .page-about .hero-fact {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }
}

@media (min-width: 820px) {
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: end;
    gap: clamp(24px, 4vw, 48px);
  }

  .page-about .origin-grid {
    grid-template-columns: repeat(12, 1fr);
    gap: clamp(24px, 3vw, 40px);
  }

  .page-about .band {
    grid-template-columns: 18fr 9fr 12fr 7fr;
  }

  .page-about .band-item {
    padding: 26px 18px 30px;
    border-left: 0;
    border-top: 4px solid var(--raise);
  }

  .page-about .band-item--eng { border-top-color: var(--cyan); }
  .page-about .band-item--fe { border-top-color: var(--indigo); }
  .page-about .band-item--content { border-top-color: var(--pulse); }
  .page-about .band-item--support { border-top-color: var(--amber); }

  .page-about .band-desc {
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    transition: max-height .26s var(--ease), opacity .2s var(--ease), margin .26s var(--ease);
  }

  .page-about .band-item:hover .band-desc,
  .page-about .band-item:focus-visible .band-desc {
    max-height: 200px;
    opacity: 1;
    margin-top: 4px;
  }

  .page-about .flow-body {
    grid-template-columns: repeat(12, 1fr);
    gap: clamp(24px, 3vw, 40px);
  }

  .page-about .flow-figure {
    margin: 0;
    position: sticky;
    top: 108px;
  }

  .page-about .tree-steps {
    margin-top: 16px;
  }

  .page-about .tl-item {
    grid-template-columns: 132px minmax(0, 1fr);
    gap: 24px;
    align-items: start;
    padding-bottom: 28px;
  }

  .page-about .tl-card {
    padding: 24px 26px 22px;
  }

  .page-about .tl-card:hover {
    transform: translateY(-4px);
  }

  .page-about .series-grid {
    grid-template-columns: repeat(4, 1fr);
  }

  .page-about .partner-copy {
    padding-left: clamp(8px, 2vw, 24px);
  }

  .page-about .cta-block {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: center;
    gap: clamp(20px, 4vw, 44px);
  }

  .page-about .cta-actions {
    flex-direction: column;
    align-items: flex-start;
  }
}

@media (min-width: 1080px) {
  .page-about .about-h1 {
    margin-bottom: 40px;
  }

  .page-about .tl-item {
    grid-template-columns: 156px minmax(0, 1fr);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .band-item,
  .page-about .band-desc,
  .page-about .tl-card,
  .page-about .step,
  .page-about .series-card,
  .page-about .tree-node .node-ring,
  .page-about .node-idx {
    transition: opacity .15s linear;
  }

  .page-about .tl-card:hover {
    transform: none;
  }
}
<<<END>>>