.page-about {
  --about-gap: 16px;
}

.page-about :where(p, h1, h2, h3, li, summary, span) {
  overflow-wrap: break-word;
}

.page-about .about-cols > *,
.page-about .timeline__item > * {
  min-width: 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-intro__lead {
  max-width: 34em;
  margin: 18px 0 0;
  font-size: 17px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-intro__meta {
  list-style: none;
  margin: 34px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px 22px;
}

.page-about .about-intro__meta li {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding-top: 12px;
  border-top: 2px solid var(--cyan);
}

.page-about .about-intro__num {
  font-family: var(--font-mono);
  font-size: 34px;
  line-height: 1.05;
  letter-spacing: -0.01em;
  color: var(--amber);
}

.page-about .about-intro__lab {
  font-size: 14px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

/* ---------- 通用小标题与说明 ---------- */
.page-about .about-sec__lead {
  max-width: 34em;
  margin: 14px 0 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-say h2 {
  margin: 12px 0 0;
}

.page-about .about-say p {
  max-width: 34em;
  margin: 14px 0 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-say--on-light h2 {
  color: var(--text-dark);
}

.page-about .about-say--on-light p {
  color: #47586A;
}

.page-about .about-say--on-light .eyebrow {
  color: var(--cyan-deep);
}

/* ---------- 非对称分栏 ---------- */
.page-about .about-cols {
  display: grid;
  gap: 34px;
}

/* ---------- 版本轨迹图 ---------- */
.page-about .about-track {
  margin: 28px 0 40px;
  aspect-ratio: 1600 / 700;
}

.page-about .media-frame img {
  display: block;
  width: 100%;
  height: 100%;
  max-width: 100%;
  object-fit: cover;
}

/* ---------- 时间线 ---------- */
.page-about .timeline {
  list-style: none;
  margin: 0;
  padding: 0 0 0 28px;
  position: relative;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 10px;
  bottom: 20px;
  width: 2px;
  background: linear-gradient(180deg, var(--cyan) 0%, rgba(53, 224, 214, 0.08) 100%);
}

.page-about .timeline__item {
  position: relative;
  display: grid;
  gap: 6px;
  padding-bottom: 32px;
}

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

.page-about .timeline__node {
  position: absolute;
  left: -28px;
  top: 4px;
  width: 14px;
  height: 14px;
  background: var(--ink);
  border: 2px solid var(--cyan);
  transform: rotate(45deg);
  transition: background var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .timeline__item:hover .timeline__node,
.page-about .timeline__item:focus-within .timeline__node {
  background: var(--cyan);
  box-shadow: 0 0 0 5px rgba(53, 224, 214, 0.16);
}

.page-about .timeline__year {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.06em;
  color: var(--amber);
}

.page-about .timeline__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: 19px;
  line-height: 1.3;
  letter-spacing: 0.03em;
  color: var(--cloud);
}

.page-about .timeline__desc {
  max-width: 34em;
  margin: 8px 0 0;
  font-size: 16px;
  line-height: 1.75;
  color: var(--muted);
  transition: color var(--dur) var(--ease);
}

.page-about .timeline__item:hover .timeline__desc {
  color: var(--cloud);
}

/* ---------- 规模数据板 ---------- */
.page-about .scale-board {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.page-about .scale-cell {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 20px 16px;
  background: rgba(244, 247, 249, 0.07);
  border-left: 3px solid var(--cyan);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--cut)), calc(100% - var(--cut)) 100%, 0 100%);
}

.page-about .scale-cell--wide {
  grid-column: 1 / -1;
}

.page-about .scale-cell__num {
  font-family: var(--font-mono);
  font-size: 40px;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--amber);
}

.page-about .scale-cell__unit {
  font-size: 16px;
  margin-left: 4px;
  letter-spacing: 0;
}

.page-about .scale-cell__lab {
  font-size: 14px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

.page-about .scale-cell__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 2px;
}

.page-about .scale-cell__tags span {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  padding: 4px 10px;
  color: var(--cyan);
  border: 1px solid rgba(53, 224, 214, 0.45);
}

/* ---------- 团队 ---------- */
.page-about .team-grid {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.page-about .team-card {
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding: 16px 14px;
  background: rgba(11, 27, 43, 0.5);
  border-top: 2px solid rgba(53, 224, 214, 0.35);
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .team-card:hover {
  border-top-color: var(--cyan);
  background: rgba(11, 27, 43, 0.82);
}

.page-about .team-card__num {
  font-family: var(--font-mono);
  font-size: 28px;
  line-height: 1;
  color: var(--amber);
}

.page-about .team-card__name {
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--cloud);
}

.page-about .team-card__desc {
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .team-shot {
  aspect-ratio: 1200 / 800;
}

/* ---------- 资质 ---------- */
.page-about .cred-badge {
  max-width: 420px;
  justify-self: start;
}

.page-about .cred-list {
  margin-top: 24px;
  border-bottom: 1px solid var(--line);
}

.page-about .cred {
  border-top: 1px solid var(--line);
}

.page-about .cred__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 15px 0;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  letter-spacing: 0.03em;
  color: var(--text-dark);
  cursor: pointer;
  list-style: none;
}

.page-about .cred__head::-webkit-details-marker {
  display: none;
}

.page-about .cred__head::after {
  content: "+";
  flex: none;
  font-family: var(--font-mono);
  font-size: 20px;
  line-height: 1;
  color: var(--cyan-deep);
  transition: transform var(--dur) var(--ease);
}

.page-about .cred[open] .cred__head::after {
  transform: rotate(45deg);
}

.page-about .cred__head:hover {
  color: var(--cyan-deep);
}

.page-about .cred__body {
  padding: 0 0 18px;
}

.page-about .cred__body p {
  max-width: 34em;
  margin: 0;
  font-size: 16px;
  line-height: 1.8;
  color: #47586A;
}

/* ---------- 合作生态 ---------- */
.page-about .partner-grid {
  margin-top: 26px;
  display: grid;
  gap: 14px;
}

.page-about .partner-panel {
  padding: 22px 20px;
  background: rgba(11, 27, 43, 0.32);
  clip-path: polygon(var(--cut) 0, 100% 0, 100% calc(100% - var(--cut)), calc(100% - var(--cut)) 100%, 0 100%, 0 var(--cut));
  transition: background var(--dur) var(--ease);
}

.page-about .partner-panel:hover {
  background: rgba(11, 27, 43, 0.6);
}

.page-about .partner-panel__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 38px;
  line-height: 1;
  color: var(--amber);
}

.page-about .partner-panel h3 {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-size: 19px;
  letter-spacing: 0.04em;
  color: var(--cloud);
}

.page-about .partner-panel p {
  max-width: 34em;
  margin: 10px 0 0;
  font-size: 16px;
  line-height: 1.8;
  color: rgba(244, 247, 249, 0.78);
}

/* ---------- 能力指标带 ---------- */
.page-about .metric-band {
  margin-top: 30px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: rgba(53, 224, 214, 0.18);
  border: 1px solid rgba(53, 224, 214, 0.18);
}

.page-about .metric {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 22px 18px;
  background: var(--ink);
  transition: background var(--dur) var(--ease);
}

.page-about .metric:hover {
  background: rgba(53, 224, 214, 0.07);
}

.page-about .metric__num {
  font-family: var(--font-mono);
  font-size: 34px;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--amber);
}

.page-about .metric__unit {
  font-size: 15px;
  margin-left: 3px;
  letter-spacing: 0;
}

.page-about .metric__lab {
  font-size: 14px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

.page-about .about-ops__note {
  max-width: 46em;
  margin: 24px 0 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 下一步 ---------- */
.page-about .next-steps {
  margin-top: 26px;
  display: grid;
  gap: 12px;
}

.page-about .next-step {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 16px;
  min-height: 106px;
  padding: 20px 18px;
  text-decoration: none;
  background: rgba(11, 27, 43, 0.5);
  border: 1px solid rgba(53, 224, 214, 0.28);
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .next-step:hover,
.page-about .next-step:focus-visible {
  border-color: var(--cyan);
  background: rgba(53, 224, 214, 0.09);
}

.page-about .next-step__k {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.page-about .next-step__t {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--cloud);
}

.page-about .next-step:hover .next-step__t {
  color: var(--cyan);
}

/* ---------- 平板 ---------- */
@media (min-width: 700px) {
  .page-about .about-intro__meta {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    max-width: 760px;
  }

  .page-about .timeline__item {
    grid-template-columns: 150px minmax(0, 1fr);
    gap: 0 22px;
    align-items: start;
  }

  .page-about .team-grid {
    gap: 14px;
  }

  .page-about .next-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 940px) {
  .page-about .about-cols {
    gap: 52px;
    align-items: start;
  }

  .page-about .about-cols--wide-left {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  }

  .page-about .about-cols--wide-right {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    align-items: center;
  }

  .page-about .about-track {
    margin: 34px 0 48px;
  }

  .page-about .scale-board {
    gap: 16px;
  }

  .page-about .team-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .partner-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
  }

  .page-about .partner-panel--wide {
    grid-column: 1 / -1;
  }

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

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

@media (min-width: 1100px) {
  .page-about .about-intro__num {
    font-size: 40px;
  }

  .page-about .scale-cell__num {
    font-size: 46px;
  }

  .page-about .metric__num {
    font-size: 40px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .timeline__node,
  .page-about .timeline__desc,
  .page-about .team-card,
  .page-about .partner-panel,
  .page-about .metric,
  .page-about .next-step,
  .page-about .cred__head::after {
    transition: none;
  }
}