.page-about {
  --about-rail-w: 56px;
  --about-node: 10px;
  --about-plate-w: 300px;
  --about-track-card: 264px;
  background: var(--ink-void);
  color: var(--white-hi);
  overflow-x: clip;
}

/* ---------- 面包屑 ---------- */
.page-about-crumbs {
  padding: 96px var(--gutter) 0;
  max-width: var(--shell);
  margin: 0 auto;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: 40px 0 clamp(64px, 9vw, 120px);
  isolation: isolate;
}

.page-about .about-hero-diagonal {
  position: absolute;
  inset: -10% -14% auto 30%;
  height: 118%;
  z-index: -1;
  background:
    linear-gradient(132deg,
      transparent 42%,
      rgba(47, 107, 255, 0.30) 42.4%,
      rgba(47, 107, 255, 0.06) 52%,
      transparent 52.4%),
    linear-gradient(152deg,
      transparent 58%,
      rgba(36, 224, 214, 0.18) 58.3%,
      transparent 66%),
    linear-gradient(115deg,
      transparent 72%,
      rgba(255, 79, 216, 0.14) 72.3%,
      transparent 78%);
  pointer-events: none;
}

.page-about .about-hero-inner {
  position: relative;
}

.page-about .about-hero .eyebrow {
  margin-bottom: 28px;
}

.page-about .about-title {
  font-family: var(--font-display);
  font-weight: 250;
  font-size: clamp(2.5rem, 8.6vw, 6.8rem);
  line-height: 0.98;
  letter-spacing: -0.03em;
  margin: 0;
  max-width: 15ch;
  text-wrap: balance;
}

.page-about .about-title-em {
  color: var(--grey-index);
  font-weight: 250;
}

.page-about .about-hero-foot {
  display: grid;
  gap: 40px;
  margin-top: clamp(40px, 6vw, 72px);
  padding-left: clamp(0px, 6vw, 96px);
}

.page-about .about-lede {
  max-width: 60ch;
  color: var(--grey-index);
  font-size: 16px;
  line-height: 1.8;
  margin: 0;
}

.page-about .about-lede--narrow {
  max-width: 68ch;
}

.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  border: 1px solid var(--line-steel);
  border-radius: var(--r-card);
  overflow: hidden;
  background: var(--line-steel);
}

.page-about .about-stat {
  background: var(--ink-slate);
  padding: 18px 20px;
}

.page-about .about-stat dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--grey-index);
}

.page-about .about-stat dd {
  margin: 8px 0 0;
  font-family: var(--font-mono);
  font-size: 24px;
  font-weight: 700;
  color: var(--cyan-signal);
  letter-spacing: -0.01em;
}

/* ---------- 通栏主图 ---------- */
.page-about .about-hero-media {
  margin: 0;
  border-top: 1px solid var(--line-steel);
  border-bottom: 1px solid var(--line-steel);
  background: var(--ink-slate);
}

.page-about .about-hero-media img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  opacity: 0.86;
}

.page-about .about-hero-caption {
  display: flex;
  gap: 16px;
  align-items: baseline;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 16px var(--gutter) 18px;
  font-size: 13px;
  color: var(--grey-index);
  border-top: 1px solid var(--line-steel);
}

/* ---------- 章节通用骨架 ---------- */
.page-about .about-chapter {
  position: relative;
  padding: clamp(72px, 10vw, 140px) 0;
}

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

.page-about .about-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
  align-items: start;
}

.page-about .about-rail {
  display: none;
  position: relative;
  width: var(--about-rail-w);
  align-self: stretch;
}

.page-about .about-rail::before {
  content: "";
  position: absolute;
  left: 50%;
  top: 0;
  bottom: 0;
  width: 1px;
  transform: translateX(-50%);
  background: linear-gradient(180deg,
    transparent,
    var(--line-steel) 12%,
    var(--line-steel) 88%,
    transparent);
}

.page-about .about-rail i {
  position: absolute;
  left: 50%;
  top: 12px;
  width: var(--about-node);
  height: var(--about-node);
  margin-left: calc(var(--about-node) / -2);
  border-radius: 50%;
  background: var(--ink-void);
  box-shadow: 0 0 0 1px var(--line-steel) inset, 0 0 0 1px var(--line-steel);
}

.page-about .about-rail i::after {
  content: "";
  position: absolute;
  inset: 2px;
  border-radius: 50%;
  background: var(--cyan-signal);
}

.page-about .about-chapter-body .eyebrow {
  margin-bottom: 16px;
}

.page-about .about-chapter-body .section-title {
  margin: 0 0 24px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.5rem, 3.4vw, 2.4rem);
  line-height: 1.2;
  letter-spacing: -0.01em;
  max-width: 22ch;
}

.page-about .about-prose {
  display: grid;
  gap: 18px;
  max-width: 64ch;
}

.page-about .about-prose p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(243, 247, 255, 0.82);
}

/* ---------- 要点列表 ---------- */
.page-about .about-points {
  list-style: none;
  margin: 32px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line-steel);
  border: 1px solid var(--line-steel);
  border-radius: var(--r-card);
  overflow: hidden;
}

.page-about .about-points li {
  background: var(--ink-slate);
  padding: 18px 20px;
  display: grid;
  gap: 6px;
}

.page-about .about-points p {
  margin: 0;
}

.page-about .about-point-title {
  font-size: 15px;
  font-weight: 700;
  color: var(--white-hi);
}

.page-about .about-points li > p:last-child {
  font-size: 14px;
  line-height: 1.7;
  color: var(--grey-index);
}

/* ---------- 展签 ---------- */
.page-about .about-plate {
  padding: 22px;
  display: grid;
  gap: 10px;
  align-content: start;
}

.page-about .about-plate .plate-label {
  margin: 0;
}

.page-about .about-plate .plate-title {
  margin: 0;
  font-size: 18px;
  font-weight: 700;
  line-height: 1.35;
  color: var(--white-hi);
}

.page-about .about-plate > p:not(.plate-label):not(.plate-title):not(.about-plate-link) {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--grey-index);
}

.page-about .about-plate-link {
  margin: 6px 0 0;
  font-size: 13px;
}

.page-about .about-plate-link a {
  color: var(--cyan-signal);
  text-decoration: none;
  border-bottom: 1px solid rgba(36, 224, 214, 0.35);
  padding-bottom: 2px;
  transition: color 200ms var(--ease), border-color 200ms var(--ease);
}

.page-about .about-plate-link a:hover,
.page-about .about-plate-link a:focus-visible {
  color: var(--white-hi);
  border-color: var(--blue-volt);
}

/* ---------- 版本章节 ---------- */
.page-about .about-chapter--version {
  background:
    radial-gradient(120% 90% at 8% 0%, rgba(47, 107, 255, 0.12), transparent 62%),
    linear-gradient(180deg, var(--ink-void), var(--ink-void));
}

.page-about .about-chapter-head {
  display: grid;
  gap: 14px;
  max-width: 72ch;
  margin-bottom: clamp(36px, 5vw, 56px);
}

.page-about .about-chapter-head .eyebrow {
  margin: 0;
}

.page-about .about-chapter-head .section-title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.5rem, 3.4vw, 2.4rem);
  line-height: 1.2;
  letter-spacing: -0.01em;
}

.page-about .about-timeline-wrap {
  padding: 0 var(--gutter);
  max-width: var(--shell);
  margin: 0 auto;
}

.page-about .about-timeline {
  position: relative;
  overflow-x: auto;
  overflow-y: hidden;
  padding: 4px 0 26px;
  scroll-snap-type: x proximity;
  scrollbar-width: thin;
  scrollbar-color: var(--line-steel) transparent;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 66px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--line-steel) 4%, var(--line-steel) 96%, transparent);
  pointer-events: none;
}

.page-about .about-timeline::-webkit-scrollbar {
  height: 6px;
}

.page-about .about-timeline::-webkit-scrollbar-thumb {
  background: var(--line-steel);
  border-radius: 999px;
}

.page-about .about-timeline:focus-visible {
  outline: 2px solid var(--cyan-signal);
  outline-offset: 6px;
  border-radius: 8px;
}

.page-about .about-track {
  position: relative;
  display: flex;
  gap: 18px;
  min-width: max-content;
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-milestone {
  flex: 0 0 var(--about-track-card);
  scroll-snap-align: start;
  position: relative;
  display: grid;
  gap: 8px;
  align-content: start;
  padding: 22px 20px 20px;
  background: var(--ink-slate);
  border: 1px solid var(--line-steel);
  border-radius: var(--r-card);
  transition: transform 220ms var(--ease), border-color 220ms var(--ease), box-shadow 220ms var(--ease);
}

.page-about .about-milestone::before {
  content: "";
  position: absolute;
  top: 56px;
  left: -19px;
  width: 19px;
  height: 1px;
  background: var(--line-steel);
}

.page-about .about-milestone:first-child::before {
  display: none;
}

.page-about .about-milestone:hover,
.page-about .about-milestone:focus-within {
  transform: translateY(-4px);
  border-color: var(--blue-volt);
  box-shadow: 0 18px 40px -28px rgba(47, 107, 255, 0.7);
}

.page-about .about-milestone-index {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--grey-index);
  transition: color 220ms var(--ease);
}

.page-about .about-milestone:hover .about-milestone-index,
.page-about .about-milestone:focus-within .about-milestone-index {
  color: var(--cyan-signal);
}

.page-about .about-milestone-name {
  margin: 0;
  font-size: 18px;
  font-weight: 700;
  color: var(--white-hi);
}

.page-about .about-milestone-summary {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--grey-index);
}

.page-about .about-milestone--major {
  border-color: rgba(36, 224, 214, 0.42);
  background:
    linear-gradient(160deg, rgba(36, 224, 214, 0.08), transparent 60%),
    var(--ink-slate);
}

.page-about .about-milestone-detail {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 280ms var(--ease);
}

.page-about .about-milestone-detail > div {
  overflow: hidden;
}

.page-about .about-milestone-detail p {
  margin: 0;
  padding-top: 10px;
  border-top: 1px dashed var(--line-steel);
  font-size: 13.5px;
  line-height: 1.75;
  color: rgba(243, 247, 255, 0.78);
}

.page-about .about-milestone:hover .about-milestone-detail,
.page-about .about-milestone:focus-within .about-milestone-detail {
  grid-template-rows: 1fr;
}

.page-about .about-timeline-hint {
  margin: 14px 0 0;
  display: flex;
  gap: 10px;
  align-items: center;
  font-size: 12.5px;
  color: var(--grey-index);
}

.page-about .about-timeline-hint .index-num {
  color: var(--cyan-signal);
}

.page-about .about-version-figure {
  margin-top: clamp(40px, 6vw, 64px);
  display: grid;
  gap: 14px;
}

.page-about .about-version-figure .media-frame {
  border: 1px solid var(--line-steel);
  border-radius: var(--r-card);
  overflow: hidden;
  background: var(--ink-slate);
}

.page-about .about-version-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  opacity: 0.9;
}

.page-about .about-figure-note {
  margin: 0;
  max-width: 60ch;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--grey-index);
}

/* ---------- 团队章节（浅雾底） ---------- */
.page-about .about-chapter--mist {
  background: var(--mist);
  color: var(--ink-deep);
}

.page-about .about-chapter--mist .eyebrow {
  color: #4a5c76;
}

.page-about .about-chapter--mist .section-title,
.page-about .about-chapter--mist .about-role-name,
.page-about .about-chapter--mist .about-team-foot {
  color: var(--ink-deep);
}

.page-about .about-team {
  display: grid;
  gap: clamp(32px, 5vw, 56px);
}

.page-about .about-team-grid {
  display: grid;
  gap: 32px;
  align-items: start;
}

.page-about .about-team-copy {
  display: grid;
  gap: 18px;
  max-width: 60ch;
}

.page-about .about-team-copy p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: #26364c;
}

.page-about .about-role-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: #cfd9e8;
  border: 1px solid #cfd9e8;
  border-radius: var(--r-card);
  overflow: hidden;
}

.page-about .about-role-list li {
  background: #ffffff;
  padding: 18px 20px;
  display: grid;
  gap: 6px;
}

.page-about .about-role-name {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  font-weight: 700;
  color: #1d3557;
}

.page-about .about-role-list li > p:last-child {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: #3c4a60;
}

.page-about .about-team-foot {
  margin: 0;
  padding-top: 22px;
  border-top: 1px solid #cfd9e8;
  max-width: 68ch;
  font-size: 14px;
  line-height: 1.8;
}

/* ---------- 设备章节 ---------- */
.page-about .about-grid--device {
  align-items: start;
}

.page-about .about-device-figure {
  margin: 0;
  border: 1px solid var(--line-steel);
  border-radius: var(--r-card);
  overflow: hidden;
  background: var(--ink-slate);
}

.page-about .about-device-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  opacity: 0.9;
}

.page-about .about-device-grid {
  margin-top: clamp(32px, 5vw, 56px);
  display: grid;
  gap: 18px;
}

.page-about .about-device-card {
  padding: 22px 20px;
  border: 1px solid var(--line-steel);
  border-radius: var(--r-card);
  background:
    linear-gradient(200deg, rgba(36, 224, 214, 0.07), transparent 55%),
    var(--ink-slate);
  display: grid;
  gap: 8px;
  align-content: start;
  transition: border-color 220ms var(--ease), transform 220ms var(--ease);
}

.page-about .about-device-card:hover,
.page-about .about-device-card:focus-within {
  transform: translateY(-4px);
  border-color: var(--cyan-signal);
}

.page-about .about-device-card .plate-label {
  margin: 0;
}

.page-about .about-device-title {
  margin: 0;
  font-size: 19px;
  font-weight: 700;
  color: var(--white-hi);
}

.page-about .about-device-card > p:last-child {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--grey-index);
}

/* ---------- 合作章节 ---------- */
.page-about .about-chapter--coop {
  background:
    radial-gradient(90% 80% at 92% 0%, rgba(255, 79, 216, 0.10), transparent 60%),
    var(--ink-void);
}

.page-about .about-coop {
  display: grid;
  gap: clamp(32px, 5vw, 52px);
}

.page-about .about-coop-grid {
  display: grid;
  gap: 18px;
}

.page-about .about-coop-card {
  padding: 26px 22px;
  border: 1px solid var(--line-steel);
  border-radius: var(--r-card);
  background: var(--ink-slate);
  display: grid;
  gap: 10px;
  align-content: start;
  transition: border-color 220ms var(--ease), transform 220ms var(--ease);
}

.page-about .about-coop-card:hover,
.page-about .about-coop-card:focus-within {
  transform: translateY(-4px);
  border-color: var(--blue-volt);
}

.page-about .about-coop-index {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--cyan-signal);
}

.page-about .about-coop-name {
  margin: 0;
  font-size: 19px;
  font-weight: 700;
  color: var(--white-hi);
}

.page-about .about-coop-card > p:last-child {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--grey-index);
}

.page-about .about-coop-foot {
  display: grid;
  gap: 24px;
  padding-top: 28px;
  border-top: 1px solid var(--line-steel);
}

.page-about .about-coop-foot > p:first-child {
  margin: 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(243, 247, 255, 0.82);
}

.page-about .about-coop-actions {
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-team-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: 40px;
  }

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

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

@media (min-width: 900px) {
  .page-about .about-grid {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr) var(--about-plate-w);
    gap: 40px;
  }

  .page-about .about-grid--device {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr) minmax(0, 400px);
  }

  .page-about .about-rail {
    display: block;
  }

  .page-about .about-hero-foot {
    grid-template-columns: minmax(0, 1fr) minmax(0, 520px);
    align-items: end;
    gap: 56px;
  }

  .page-about .about-plate {
    margin-top: 56px;
  }

  .page-about .about-chapter:nth-of-type(even) .about-plate {
    margin-top: 0;
  }

  .page-about .about-chapter:nth-of-type(even) .about-chapter-body {
    margin-top: 40px;
  }

  .page-about .about-track {
    gap: 24px;
  }

  .page-about .about-coop-foot {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: end;
    gap: 40px;
  }

  .page-about .about-coop-actions {
    justify-content: flex-end;
  }
}

@media (min-width: 1200px) {
  .page-about {
    --about-track-card: 288px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-milestone,
  .page-about .about-device-card,
  .page-about .about-coop-card,
  .page-about .about-plate-link a,
  .page-about .about-milestone-detail {
    transition: none;
  }

  .page-about .about-milestone:hover,
  .page-about .about-milestone:focus-within,
  .page-about .about-device-card:hover,
  .page-about .about-device-card:focus-within,
  .page-about .about-coop-card:hover,
  .page-about .about-coop-card:focus-within {
    transform: none;
  }
}
<<<END>>>