.page-about {
  --about-rule: rgba(201, 162, 39, 0.28);
  --about-rule-soft: rgba(201, 162, 39, 0.12);
  --about-panel: #1A1B1F;
  --about-panel-2: #2A2C33;
  background: var(--ink);
  color: var(--cream);
  overflow-x: clip;
}

.page-about .sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(28px, 5vw, 48px) 0 clamp(52px, 7vw, 84px);
  border-bottom: 1px solid var(--about-rule-soft);
  background:
    radial-gradient(120% 90% at 88% 0%, rgba(201, 162, 39, 0.14) 0%, rgba(201, 162, 39, 0) 58%),
    radial-gradient(80% 70% at 4% 100%, rgba(142, 43, 51, 0.16) 0%, rgba(142, 43, 51, 0) 62%),
    repeating-linear-gradient(90deg, rgba(201, 162, 39, 0.045) 0 1px, transparent 1px 96px),
    var(--ink);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 1px;
  background: linear-gradient(90deg, var(--gold-deep), rgba(201, 162, 39, 0));
}

.page-about .hero-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(32px, 5vw, 56px);
  margin-top: clamp(28px, 4vw, 44px);
}

.page-about .hero-kicker {
  font-size: var(--step-1);
  letter-spacing: 0.22em;
  color: var(--gold);
  margin: 0 0 18px;
}

.page-about h1 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(34px, 5.4vw, 62px);
  line-height: 1.06;
  letter-spacing: -0.02em;
  margin: 0 0 22px;
  max-width: 18ch;
}

.page-about .hero-lead {
  font-size: var(--step0);
  line-height: 1.8;
  color: rgba(244, 240, 230, 0.82);
  max-width: 62ch;
  margin: 0 0 30px;
}

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

.page-about .hero-facts {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  background: var(--about-rule-soft);
  border: 1px solid var(--about-rule);
}

.page-about .fact {
  background: var(--charcoal);
  padding: 18px 14px 20px;
  min-width: 0;
}

.page-about .fact dt {
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--steel);
  margin-bottom: 10px;
  white-space: nowrap;
}

.page-about .fact dd {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(20px, 3vw, 30px);
  color: var(--gold-light);
  letter-spacing: 0.01em;
  white-space: nowrap;
}

/* ---------- 主体两栏 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(36px, 6vw, 64px);
  padding-top: clamp(48px, 7vw, 88px);
  padding-bottom: clamp(64px, 9vw, 128px);
}

.page-about .about-content {
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: clamp(72px, 10vw, 132px);
}

/* ---------- 年份刻度轴 ---------- */
.page-about .year-rail {
  min-width: 0;
}

.page-about .year-rail-title {
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--steel);
  margin: 0 0 16px;
}

.page-about .year-rail-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .year-rail-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 66px;
  padding: 8px 10px;
  font-size: 14px;
  letter-spacing: 0.06em;
  color: var(--steel);
  text-decoration: none;
  border: 1px solid var(--about-rule-soft);
  background: var(--charcoal);
  transition: color 180ms var(--ease), border-color 180ms var(--ease), background 180ms var(--ease);
}

.page-about .year-rail-link:hover,
.page-about .year-rail-link:focus-visible {
  color: var(--gold-light);
  border-color: var(--about-rule);
}

.page-about .year-rail-link:focus-visible {
  outline: 2px solid var(--gold-light);
  outline-offset: 2px;
}

.page-about .year-rail-link.is-active {
  color: var(--ink);
  background: var(--gold);
  border-color: var(--gold);
}

.page-about .year-rail-link.is-active span {
  color: var(--ink);
}

.page-about .year-rail-hint {
  margin: 14px 0 0;
  font-size: 13px;
  color: var(--steel);
}

/* ---------- 章节通用 ---------- */
.page-about .chapter {
  min-width: 0;
  scroll-margin-top: calc(var(--header-h) + 24px);
}

.page-about .chapter-head {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  padding-bottom: 22px;
  margin-bottom: clamp(28px, 4vw, 44px);
  border-bottom: 1px solid var(--about-rule-soft);
}

.page-about .chapter-num {
  font-size: clamp(38px, 6vw, 62px);
  line-height: 1;
  color: transparent;
  -webkit-text-stroke: 1px var(--gold-deep);
  letter-spacing: 0.02em;
  margin: 0;
}

.page-about .chapter-title {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(24px, 3.4vw, 38px);
  line-height: 1.24;
  letter-spacing: -0.01em;
  margin: 0 0 12px;
  max-width: 26ch;
}

.page-about .chapter-lead {
  font-size: var(--step0);
  line-height: 1.78;
  color: rgba(244, 240, 230, 0.76);
  max-width: 68ch;
  margin: 0;
}

.page-about a {
  color: var(--gold-light);
  text-decoration: underline;
  text-decoration-color: rgba(201, 162, 39, 0.5);
  text-underline-offset: 4px;
}

.page-about a:hover {
  color: var(--gold);
  text-decoration-color: var(--gold);
}

/* ---------- 图片容器 ---------- */
.page-about .figure {
  margin: 0 0 clamp(32px, 4.5vw, 52px);
}

.page-about .figure-frame {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--about-rule);
  background:
    repeating-linear-gradient(135deg, rgba(201, 162, 39, 0.08) 0 2px, transparent 2px 9px),
    var(--charcoal);
}

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

.page-about .figure-caption {
  margin-top: 10px;
  font-size: 13px;
  color: var(--steel);
}

.page-about .timeline-banner .figure-frame {
  max-height: 340px;
}

.page-about .matrix-plate .figure-frame {
  aspect-ratio: 3 / 4;
  max-height: 320px;
  max-width: 240px;
}

.page-about .lines-map .figure-frame {
  max-height: 380px;
}

/* ---------- 年表 ---------- */
.page-about .timeline {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: clamp(26px, 3.6vw, 40px);
  padding-left: 34px;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 6px;
  bottom: 6px;
  width: 1px;
  background: linear-gradient(180deg, var(--gold), var(--about-rule-soft) 82%, transparent);
}

.page-about .tl-node {
  position: relative;
  border: 1px solid var(--about-rule-soft);
  background: var(--charcoal);
  padding: 18px 18px 20px;
  transition: border-color 200ms var(--ease), background 200ms var(--ease);
}

.page-about .tl-node:hover {
  border-color: var(--about-rule);
}

.page-about .tl-node.is-active {
  border-color: var(--gold);
  background: var(--about-panel-2);
}

.page-about .tl-dot {
  position: absolute;
  left: -34px;
  top: 24px;
  width: 15px;
  height: 15px;
  border-radius: 50%;
  background: var(--ink);
  border: 2px solid var(--gold-deep);
}

.page-about .tl-node.is-active .tl-dot {
  border-color: var(--gold);
  box-shadow: 0 0 0 4px rgba(201, 162, 39, 0.16);
}

.page-about .tl-year {
  font-size: var(--step1);
  color: var(--gold);
  letter-spacing: 0.16em;
  margin: 0 0 8px;
}

.page-about .tl-title {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(19px, 2.4vw, 24px);
  line-height: 1.4;
  margin: 0 0 10px;
}

.page-about .tl-text {
  margin: 0;
  font-size: var(--step0);
  line-height: 1.78;
  color: rgba(244, 240, 230, 0.74);
  max-width: 64ch;
}

/* ---------- 版本对照表 ---------- */
.page-about .matrix-panel {
  background: var(--paper);
  color: var(--ink);
  border: 1px solid var(--gold-deep);
}

.page-about .matrix-head {
  padding: 20px 20px 18px;
  border-bottom: 1px solid rgba(140, 109, 31, 0.32);
  background:
    repeating-linear-gradient(90deg, rgba(140, 109, 31, 0.06) 0 1px, transparent 1px 12px),
    var(--cream);
}

.page-about .matrix-title {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(17px, 2.2vw, 21px);
  color: var(--ink);
}

.page-about .matrix-sub {
  margin: 0;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: #6B5A2B;
}

.page-about .table-wrap {
  overflow-x: auto;
  overscroll-behavior-x: contain;
  -webkit-overflow-scrolling: touch;
}

.page-about .table-wrap:focus-visible {
  outline: 2px solid var(--gold);
  outline-offset: -2px;
}

.page-about .table-wrap::-webkit-scrollbar {
  height: 10px;
}

.page-about .table-wrap::-webkit-scrollbar-track {
  background: var(--cream);
}

.page-about .table-wrap::-webkit-scrollbar-thumb {
  background: var(--gold-deep);
  border: 2px solid var(--cream);
}

.page-about .matrix-panel .data-table {
  width: 100%;
  min-width: 600px;
  border-collapse: collapse;
  font-size: 15px;
  color: var(--ink);
}

.page-about .matrix-panel .data-table thead th {
  background: var(--graphite);
  color: var(--gold-light);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-align: left;
  padding: 12px 14px;
  white-space: nowrap;
}

.page-about .matrix-panel .data-table tbody tr {
  border-bottom: 1px solid rgba(140, 109, 31, 0.18);
  transition: background 160ms var(--ease);
}

.page-about .matrix-panel .data-table tbody tr:nth-child(even) {
  background: rgba(140, 109, 31, 0.045);
}

.page-about .matrix-panel .data-table tbody tr:hover {
  background: rgba(201, 162, 39, 0.16);
}

.page-about .matrix-panel .data-table th,
.page-about .matrix-panel .data-table td {
  padding: 13px 14px;
  text-align: left;
  vertical-align: middle;
  white-space: nowrap;
}

.page-about .matrix-panel .col-ver {
  font-family: var(--font-mono);
  font-size: 16px;
  letter-spacing: 0.04em;
  color: var(--ink);
  display: flex;
  align-items: center;
  gap: 10px;
}

.page-about .copy-btn {
  font-size: 11px;
  letter-spacing: 0.08em;
  padding: 3px 8px;
  border: 1px solid rgba(140, 109, 31, 0.5);
  background: transparent;
  color: #6B5A2B;
  cursor: pointer;
  opacity: 0;
  transition: opacity 160ms var(--ease), background 160ms var(--ease), color 160ms var(--ease);
}

.page-about .matrix-panel .data-table tbody tr:hover .copy-btn,
.page-about .copy-btn:focus-visible {
  opacity: 1;
}

.page-about .copy-btn:hover {
  background: var(--gold);
  border-color: var(--gold);
  color: var(--ink);
}

.page-about .copy-btn.is-copied {
  opacity: 1;
  background: var(--gold-deep);
  border-color: var(--gold-deep);
  color: var(--paper);
}

.page-about .state {
  display: inline-block;
  font-size: 12px;
  letter-spacing: 0.1em;
  padding: 3px 10px;
  border: 1px solid currentColor;
  white-space: nowrap;
}

.page-about .state--live {
  color: #7A6012;
  background: rgba(201, 162, 39, 0.14);
}

.page-about .state--hold {
  color: var(--crimson);
  background: rgba(142, 43, 51, 0.1);
}

.page-about .state--arch {
  color: #4E5A63;
  background: rgba(110, 124, 134, 0.14);
}

.page-about .matrix-foot {
  margin: 0;
  padding: 16px 20px 20px;
  font-size: 14px;
  line-height: 1.72;
  color: #4A4433;
  border-top: 1px solid rgba(140, 109, 31, 0.24);
}

.page-about .matrix-foot a {
  color: #7A6012;
  text-decoration-color: rgba(140, 109, 31, 0.55);
}

.page-about .matrix-foot a:hover {
  color: var(--ink);
}

/* ---------- 四条产品线 ---------- */
.page-about .lines-list {
  display: flex;
  flex-direction: column;
  gap: 1px;
  background: var(--about-rule-soft);
  border: 1px solid var(--about-rule-soft);
}

.page-about .line-row {
  background: var(--charcoal);
  padding: 20px 18px 22px;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-about .line-head {
  display: flex;
  align-items: baseline;
  gap: 10px;
}

.page-about .line-no {
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--gold-deep);
}

.page-about .line-name {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(18px, 2.3vw, 22px);
  margin: 0;
}

.page-about .line-track {
  position: relative;
  height: 26px;
  background: var(--graphite);
  border: 1px solid var(--about-rule-soft);
  display: flex;
  align-items: center;
  cursor: default;
}

.page-about .line-span {
  display: block;
  height: 8px;
  margin-left: var(--span-from, 2%);
  width: var(--span-w, 96%);
  background: linear-gradient(90deg, var(--gold-deep), var(--gold));
}

.page-about .line-span--classic {
  --span-from: 0%;
  --span-w: 100%;
}

.page-about .line-span--lite {
  --span-from: 14%;
  --span-w: 84%;
}

.page-about .line-span--vault {
  --span-from: 26%;
  --span-w: 66%;
}

.page-about .line-span--turbo {
  --span-from: 42%;
  --span-w: 58%;
}

.page-about .line-chip {
  position: absolute;
  right: 8px;
  top: 50%;
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--ink);
  background: var(--gold-light);
  padding: 2px 7px;
  opacity: 0;
  transform: translate(0, -50%) translateX(6px);
  transition: opacity 180ms var(--ease), transform 180ms var(--ease);
  pointer-events: none;
  white-space: nowrap;
}

.page-about .line-track:hover .line-chip,
.page-about .line-track:focus-within .line-chip {
  opacity: 1;
  transform: translate(0, -50%) translateX(0);
}

.page-about .line-note {
  margin: 0;
  font-size: var(--step0);
  line-height: 1.78;
  color: rgba(244, 240, 230, 0.74);
  max-width: 66ch;
}

/* ---------- 团队 ---------- */
.page-about .team-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--about-rule-soft);
  border: 1px solid var(--about-rule-soft);
  margin-bottom: clamp(24px, 3vw, 36px);
}

.page-about .team-card {
  background: var(--charcoal);
  padding: 22px 18px 24px;
}

.page-about .team-no {
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--gold-deep);
  margin: 0 0 12px;
}

.page-about .team-name {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(18px, 2.3vw, 21px);
  margin: 0 0 6px;
}

.page-about .team-count {
  font-size: var(--step1);
  color: var(--gold);
  letter-spacing: 0.06em;
  margin: 0 0 12px;
}

.page-about .team-desc {
  margin: 0;
  font-size: 15px;
  line-height: 1.76;
  color: rgba(244, 240, 230, 0.72);
}

.page-about .reach-strip {
  border-left: 2px solid var(--crimson);
  background: var(--about-panel-2);
  padding: 18px 18px 18px 20px;
}

.page-about .reach-line {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(244, 240, 230, 0.8);
  max-width: 72ch;
}

/* ---------- 服务规范 ---------- */
.page-about .service-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--about-rule-soft);
}

.page-about .service-item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 8px;
  padding: 20px 0;
  border-bottom: 1px solid var(--about-rule-soft);
}

.page-about .service-no {
  font-size: 13px;
  letter-spacing: 0.18em;
  color: var(--gold-deep);
}

.page-about .service-title {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(17px, 2.2vw, 20px);
  margin: 0 0 8px;
}

.page-about .service-item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.76;
  color: rgba(244, 240, 230, 0.74);
  max-width: 66ch;
}

/* ---------- 状态标记 ---------- */
.page-about .status-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
}

.page-about .status-card {
  border: 1px solid var(--about-rule-soft);
  background: var(--charcoal);
  padding: 20px 18px 22px;
}

.page-about .status-card--live {
  border-top: 3px solid var(--gold);
}

.page-about .status-card--hold {
  border-top: 3px solid var(--crimson);
}

.page-about .status-card--arch {
  border-top: 3px solid var(--steel);
}

.page-about .status-card h3 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(17px, 2.2vw, 20px);
  margin: 14px 0 10px;
}

.page-about .status-card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: rgba(244, 240, 230, 0.74);
}

.page-about .status-tail {
  margin: 26px 0 0;
  font-size: 15px;
  line-height: 1.78;
  color: rgba(244, 240, 230, 0.66);
  max-width: 68ch;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .team-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

@media (min-width: 900px) {
  .page-about .about-body {
    padding-left: var(--gutter);
    padding-right: var(--gutter);
  }

  .page-about .hero-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: end;
  }

  .page-about .chapter-head {
    grid-template-columns: 120px minmax(0, 1fr);
    gap: 24px;
    align-items: start;
  }

  .page-about .chapter-num {
    position: sticky;
    top: calc(var(--header-h) + 26px);
  }

  .page-about .timeline {
    padding-left: 46px;
  }

  .page-about .timeline::before {
    left: 9px;
  }

  .page-about .tl-dot {
    left: -46px;
  }

  .page-about .line-row {
    grid-template-columns: 200px minmax(0, 1fr);
    column-gap: 24px;
    align-items: center;
    padding: 24px 22px;
  }

  .page-about .line-head {
    grid-column: 1;
  }

  .page-about .line-track {
    grid-column: 2;
  }

  .page-about .line-note {
    grid-column: 2;
  }

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

  .page-about .service-item {
    grid-template-columns: 64px minmax(0, 1fr);
    gap: 18px;
    align-items: start;
  }
}

@media (min-width: 1100px) {
  .page-about .about-body {
    grid-template-columns: 176px minmax(0, 1fr);
    column-gap: clamp(48px, 5vw, 88px);
  }

  .page-about .year-rail {
    position: sticky;
    top: calc(var(--header-h) + 32px);
    align-self: start;
    max-height: calc(100vh - var(--header-h) - 56px);
    overflow-y: auto;
  }

  .page-about .year-rail-list {
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 1px;
    background: var(--about-rule-soft);
    border-left: 1px solid var(--about-rule);
  }

  .page-about .year-rail-link {
    position: relative;
    justify-content: flex-start;
    min-width: 0;
    width: 100%;
    padding: 14px 12px 14px 18px;
    background: var(--charcoal);
    border: 0;
    border-left: 2px solid transparent;
  }

  .page-about .year-rail-link::before {
    content: "";
    position: absolute;
    left: -5px;
    top: 50%;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--graphite);
    transform: translateY(-50%);
    transition: background 180ms var(--ease);
  }

  .page-about .year-rail-link:hover::before {
    background: var(--gold-deep);
  }

  .page-about .year-rail-link.is-active {
    background: transparent;
    color: var(--gold-light);
    border-left-color: var(--gold);
  }

  .page-about .year-rail-link.is-active span {
    color: var(--gold-light);
  }

  .page-about .year-rail-link.is-active::before {
    background: var(--crimson);
  }

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

  .page-about .matrix-plate {
    float: right;
    width: 240px;
    margin: 0 0 24px 32px;
  }

  .page-about .lines-map {
    max-width: 72%;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .year-rail-link,
  .page-about .tl-node,
  .page-about .line-chip,
  .page-about .copy-btn,
  .page-about .matrix-panel .data-table tbody tr {
    transition: none;
  }
}
<<<END>>>