.page-about {
  --about-rule: rgba(44, 58, 107, .65);
  --about-rule-soft: rgba(44, 58, 107, .38);
  --about-node-glow: rgba(51, 242, 212, .5);
  background: var(--ink-900);
  color: var(--text);
  overflow-x: hidden;
}

.page-about a:focus-visible,
.page-about summary:focus-visible,
.page-about .dot:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
  border-radius: var(--r-sm);
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding: calc(var(--header-h) + 18px) var(--gutter) 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--muted);
}

.page-about .breadcrumbs a {
  color: var(--muted);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}

.page-about .breadcrumbs a:hover {
  color: var(--cyan);
  border-bottom-color: var(--cyan-line);
}

.page-about .crumb-sep {
  color: var(--ink-500);
}

.page-about .crumb-current {
  color: var(--text);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-block: clamp(26px, 4vw, 52px) clamp(44px, 6vw, 82px);
}

.page-about .hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 32px;
  align-items: end;
}

.page-about .about-hero h1 {
  margin: 14px 0 18px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(34px, 7.4vw, 62px);
  line-height: 1.08;
  letter-spacing: -.015em;
  color: var(--white);
}

.page-about .about-hero h1 em {
  font-style: normal;
  color: var(--cyan);
  text-shadow: 0 0 26px rgba(51, 242, 212, .3);
}

.page-about .hero-lede {
  max-width: 58ch;
  margin: 0;
  font-size: 16px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.page-about .hero-board {
  position: relative;
  padding: 20px 20px 14px;
  border: 1px solid var(--about-rule);
  border-radius: var(--r-lg);
  background: linear-gradient(165deg, var(--ink-700) 0%, var(--ink-800) 58%, var(--ink-850) 100%);
  box-shadow: 0 18px 42px rgba(4, 8, 26, .45);
  overflow: hidden;
}

.page-about .hero-board::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 82px;
  height: 2px;
  background: var(--cyan);
}

.page-about .board-title {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--cyan);
}

.page-about .board-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .board-list li {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px;
  padding: 12px 0;
  border-bottom: 1px dashed var(--about-rule-soft);
  font-size: 13px;
  color: var(--muted);
}

.page-about .board-list li:last-child {
  border-bottom: 0;
}

.page-about .board-val {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 18px;
  font-weight: 600;
  color: var(--cyan);
  white-space: nowrap;
}

.page-about .board-val--amber {
  color: var(--amber);
}

/* ---------- 通用章节头 ---------- */
.page-about .section-head {
  max-width: 730px;
  margin: 0 0 30px;
}

.page-about .section-head h2 {
  margin: 10px 0 14px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(28px, 4.6vw, 44px);
  line-height: 1.14;
  letter-spacing: -.01em;
  color: var(--white);
}

.page-about .section-lede {
  margin: 0;
  font-size: 16px;
  line-height: 1.85;
  color: var(--muted);
}

/* ---------- 团队 ---------- */
.page-about .team-block {
  padding-block: clamp(44px, 6vw, 78px);
  border-top: 1px solid var(--about-rule-soft);
}

.page-about .team-figure {
  margin: 0 0 26px;
}

.page-about .role-board {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .role-card {
  position: relative;
  padding: 26px 18px 20px;
  border: 1px solid var(--about-rule);
  border-radius: var(--r-md);
  background: var(--ink-800);
  transition: border-color .25s var(--ease), transform .25s var(--ease);
}

.page-about .role-card::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 18px;
  width: 34px;
  height: 2px;
  background: var(--cyan);
}

.page-about .role-card[data-accent="amber"]::before {
  background: var(--amber);
}

.page-about .role-card:hover {
  border-color: var(--cyan-line);
  transform: translateY(-3px);
}

.page-about .role-index {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--ink-500);
}

.page-about .role-card h3 {
  margin: 10px 0 4px;
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 800;
  color: var(--white);
}

.page-about .role-count {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 26px;
  font-weight: 600;
  line-height: 1;
  color: var(--cyan);
}

.page-about .role-card[data-accent="amber"] .role-count {
  color: var(--amber);
}

.page-about .role-desc {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 发展阶段 ---------- */
.page-about .eras {
  padding-block: clamp(48px, 6vw, 82px);
  border-top: 1px solid var(--about-rule-soft);
  background:
    radial-gradient(760px 320px at 12% 4%, rgba(51, 242, 212, .06), transparent 70%),
    var(--ink-900);
}

.page-about .era-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .era-item {
  display: grid;
  grid-template-columns: 26px minmax(0, 1fr);
  gap: 14px;
}

.page-about .era-axis {
  position: relative;
  display: flex;
  justify-content: center;
}

.page-about .era-axis::before {
  content: "";
  position: absolute;
  top: 18px;
  bottom: -22px;
  width: 1px;
  background: var(--about-rule);
}

.page-about .era-item:last-child .era-axis::before {
  display: none;
}

.page-about .era-node {
  position: relative;
  z-index: 1;
  width: 10px;
  height: 10px;
  margin-top: 22px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 4px rgba(51, 242, 212, .14), 0 0 14px var(--about-node-glow);
}

.page-about .era-body {
  margin-bottom: 22px;
  padding: 20px 18px 22px;
  border: 1px solid var(--about-rule);
  border-radius: var(--r-md);
  background: var(--ink-800);
}

.page-about .era-tag {
  display: inline-block;
  padding: 3px 10px;
  border: 1px solid var(--amber-line);
  border-radius: 999px;
  background: var(--amber-soft);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--amber);
}

.page-about .era-body h3 {
  margin: 12px 0 10px;
  font-family: var(--font-display);
  font-size: clamp(20px, 3vw, 26px);
  font-weight: 800;
  line-height: 1.3;
  color: var(--white);
}

.page-about .era-body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .era-metrics {
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
}

.page-about .era-metrics li {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  padding: 9px 0;
  border-bottom: 1px solid var(--amber-line);
  font-size: 12.5px;
  color: var(--muted);
}

.page-about .era-metrics strong {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
  white-space: nowrap;
}

.page-about .era-more {
  margin-top: 18px;
}

.page-about .era-more > summary {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 7px 14px;
  border: 1px solid var(--about-rule);
  border-radius: 999px;
  background: rgba(51, 242, 212, .06);
  font-size: 12.5px;
  color: var(--cyan);
  cursor: pointer;
  list-style: none;
  transition: border-color .22s var(--ease), background .22s var(--ease);
}

.page-about .era-more > summary::-webkit-details-marker {
  display: none;
}

.page-about .era-more > summary::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1;
}

.page-about .era-more[open] > summary::after {
  content: "–";
}

.page-about .era-more > summary:hover {
  border-color: var(--cyan-line);
  background: var(--cyan-soft);
}

.page-about .era-more ul {
  list-style: none;
  margin: 14px 0 0;
  padding: 0;
  display: grid;
  gap: 9px;
}

.page-about .era-more li {
  position: relative;
  padding-left: 18px;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .era-more li::before {
  content: "";
  position: absolute;
  top: 9px;
  left: 2px;
  width: 5px;
  height: 5px;
  background: var(--cyan-line);
  transform: rotate(45deg);
}

/* ---------- 数据来源 ---------- */
.page-about .sources {
  padding-block: clamp(48px, 6vw, 84px);
  border-top: 1px solid var(--about-rule-soft);
}

.page-about .sources-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 30px;
}

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

.page-about .sources-text h2 {
  margin: 10px 0 14px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(26px, 4.2vw, 40px);
  line-height: 1.16;
  color: var(--white);
}

.page-about .source-steps {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  gap: 14px;
  counter-reset: step;
}

.page-about .source-steps li {
  position: relative;
  padding-left: 46px;
  font-size: 15px;
  line-height: 1.78;
  color: var(--muted);
}

.page-about .source-steps li::before {
  counter-increment: step;
  content: counter(step, decimal-leading-zero);
  position: absolute;
  top: 1px;
  left: 0;
  padding: 2px 6px;
  border: 1px solid var(--cyan-line);
  border-radius: var(--r-sm);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--cyan);
}

/* ---------- 合作生态 ---------- */
.page-about .eco {
  padding-block: clamp(48px, 6vw, 84px);
  border-top: 1px solid var(--about-rule-soft);
  border-bottom: 1px solid var(--about-rule-soft);
  background:
    radial-gradient(880px 360px at 16% 0%, rgba(51, 242, 212, .07), transparent 70%),
    radial-gradient(760px 340px at 88% 100%, rgba(255, 168, 58, .07), transparent 72%),
    var(--ink-850);
}

.page-about .eco-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 34px;
}

.page-about .eco-block h3 {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 800;
  color: var(--white);
}

.page-about .eco-count {
  margin: 0 0 16px;
  font-size: 13px;
  color: var(--muted);
}

.page-about .eco-count span {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 30px;
  font-weight: 600;
  color: var(--cyan);
  margin-right: 4px;
}

.page-about .eco-count--amber span {
  color: var(--amber);
}

.page-about .dot-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  max-width: 520px;
}

.page-about .dot {
  position: relative;
  width: 22px;
  height: 22px;
  border: 1px solid var(--ink-600);
  border-radius: 5px;
  background: var(--ink-700);
  cursor: default;
  transition: background .22s var(--ease), border-color .22s var(--ease), transform .22s var(--ease);
}

.page-about .dot--data:hover,
.page-about .dot--data:focus-visible {
  border-color: var(--cyan);
  background: var(--cyan-soft);
  transform: translateY(-2px);
}

.page-about .dot--org:hover,
.page-about .dot--org:focus-visible {
  border-color: var(--amber);
  background: var(--amber-soft);
  transform: translateY(-2px);
}

.page-about .dot::after {
  content: attr(data-label);
  position: absolute;
  bottom: calc(100% + 9px);
  left: 50%;
  padding: 3px 7px;
  border: 1px solid var(--about-rule);
  border-radius: var(--r-sm);
  background: var(--ink-700);
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .04em;
  white-space: nowrap;
  color: var(--text);
  opacity: 0;
  pointer-events: none;
  transform: translateX(-50%) translateY(4px);
  transition: opacity .2s var(--ease), transform .2s var(--ease);
  z-index: 3;
}

.page-about .dot--data::after {
  border-color: var(--cyan-line);
}

.page-about .dot--org::after {
  border-color: var(--amber-line);
}

.page-about .dot:hover::after,
.page-about .dot:focus-visible::after {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.page-about .eco-note {
  margin: 18px 0 0;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 资质与荣誉 ---------- */
.page-about .creds {
  padding-block: clamp(48px, 6vw, 84px);
}

.page-about .cred-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
}

.page-about .cred-card {
  padding: 24px 20px 22px;
  border: 1px solid var(--about-rule);
  border-radius: var(--r-md);
  background: linear-gradient(180deg, var(--ink-800), var(--ink-850));
}

.page-about .cred-num {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(34px, 5vw, 44px);
  font-weight: 600;
  line-height: 1;
  color: var(--amber);
}

.page-about .cred-card h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  color: var(--white);
}

.page-about .cred-card p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.72;
  color: var(--muted);
}

/* ---------- 服务场景 ---------- */
.page-about .scenes {
  padding-block: clamp(48px, 6vw, 84px);
  border-top: 1px solid var(--about-rule-soft);
}

.page-about .scene-band {
  margin: 0 auto 28px;
  max-width: var(--shell);
}

.page-about .scene-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
}

.page-about .scene-card {
  padding: 22px 18px;
  border: 1px solid var(--about-rule);
  border-radius: var(--r-md);
  background: var(--ink-800);
  border-left: 2px solid var(--cyan-line);
}

.page-about .scene-card h3 {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 800;
  color: var(--white);
}

.page-about .scene-card p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.78;
  color: var(--muted);
}

/* ---------- 收尾 ---------- */
.page-about .about-cta {
  padding-block: clamp(52px, 7vw, 92px);
  border-top: 1px solid var(--about-rule-soft);
  background: linear-gradient(180deg, var(--ink-900), var(--ink-850));
}

.page-about .cta-panel {
  position: relative;
  padding: clamp(28px, 5vw, 52px);
  border: 1px solid var(--about-rule);
  border-radius: var(--r-lg);
  background: linear-gradient(140deg, rgba(30, 42, 86, .92), rgba(13, 20, 56, .94));
  overflow: hidden;
}

.page-about .cta-panel::after {
  content: "";
  position: absolute;
  top: -70px;
  right: -60px;
  width: 230px;
  height: 230px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(51, 242, 212, .18), transparent 68%);
  pointer-events: none;
}

.page-about .cta-panel h2 {
  position: relative;
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(24px, 3.8vw, 36px);
  line-height: 1.2;
  color: var(--white);
}

.page-about .cta-panel p {
  position: relative;
  max-width: 62ch;
  margin: 0;
  font-size: 15.5px;
  line-height: 1.82;
  color: var(--muted);
}

.page-about .cta-actions {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

/* ---------- 右侧常驻索引 ---------- */
.page-about .about-index {
  display: none;
}

/* ---------- 响应式 ---------- */
@media (min-width: 620px) {
  .page-about .role-board {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

@media (min-width: 720px) {
  .page-about .era-item {
    grid-template-columns: 40px minmax(0, 1fr);
    gap: 26px;
  }

  .page-about .era-body {
    padding: 26px 26px 24px;
  }

  .page-about .hero-lede {
    font-size: 17px;
  }
}

@media (min-width: 860px) {
  .page-about .eco-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 48px;
  }

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

@media (min-width: 900px) {
  .page-about .hero-grid {
    grid-template-columns: minmax(0, 1.6fr) minmax(270px, .9fr);
    gap: 56px;
  }

  .page-about .sources-grid {
    grid-template-columns: minmax(0, .82fr) minmax(0, 1.18fr);
    gap: 52px;
    align-items: center;
  }

  .page-about .era-inner {
    display: grid;
    grid-template-columns: minmax(0, 1.35fr) minmax(200px, .65fr);
    gap: 32px;
    align-items: start;
  }

  .page-about .era-metrics {
    margin-top: 4px;
  }
}

@media (min-width: 1080px) {
  .page-about .role-board {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 1420px) {
  .page-about .about-index {
    display: flex;
    flex-direction: column;
    gap: 10px;
    position: fixed;
    top: 50%;
    right: 20px;
    z-index: 30;
    padding: 14px 10px;
    border: 1px solid var(--about-rule-soft);
    border-radius: 999px;
    background: rgba(20, 28, 68, .72);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    transform: translateY(-50%);
  }

  .page-about .about-index a {
    width: 9px;
    height: 9px;
    border-radius: 50%;
    background: var(--ink-600);
    transition: background .2s var(--ease), box-shadow .2s var(--ease);
  }

  .page-about .about-index a:hover,
  .page-about .about-index a:focus-visible {
    background: var(--cyan);
    box-shadow: 0 0 0 3px rgba(51, 242, 212, .18);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .role-card,
  .page-about .dot,
  .page-about .era-more > summary,
  .page-about .breadcrumbs a {
    transition: none;
  }

  .page-about .role-card:hover,
  .page-about .dot:hover,
  .page-about .dot:focus-visible {
    transform: none;
  }
}