.page-about {
  --about-rail-w: 236px;
  display: block;
  background: var(--canvas);
  color: var(--graphite);
}

/* ---------- 面包屑与首屏 ---------- */

.page-about .about-crumb {
  padding-top: 1.4rem;
}

.page-about .about-hero {
  padding: clamp(1.6rem, 5vw, 3.2rem) 0 clamp(1.8rem, 4vw, 2.8rem);
}

.page-about .about-hero__eyebrow {
  margin: 0 0 1rem;
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--copper);
}

.page-about .about-hero__title {
  margin: 0 0 1.3rem;
  max-width: 22ch;
  font-size: clamp(2rem, 7vw, 3.5rem);
  font-weight: 900;
  line-height: 1.16;
  letter-spacing: -0.022em;
  color: var(--graphite);
}

.page-about .about-hero__lede {
  margin: 0;
  max-width: 60ch;
  font-size: clamp(1rem, 2.3vw, 1.12rem);
  line-height: 1.9;
  color: var(--muted);
}

.page-about .about-hero__facts {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
  margin: 1.9rem 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-hero__facts li {
  padding: 0.42rem 0.92rem;
  border: 1px solid rgba(192, 138, 62, 0.34);
  border-radius: 999px;
  background: rgba(192, 138, 62, 0.12);
  font-family: var(--mono);
  font-size: 0.76rem;
  letter-spacing: 0.06em;
  color: var(--ink);
}

/* ---------- 宽幅城市图 ---------- */

.page-about .about-visual {
  margin: 0;
  padding: 0;
}

.page-about .about-visual img {
  display: block;
  width: 100%;
  height: clamp(220px, 36vw, 440px);
  object-fit: cover;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 46px), 0 100%);
}

.page-about .about-visual__caption {
  padding: 1rem 1.2rem 0;
  font-family: var(--mono);
  font-size: 0.76rem;
  letter-spacing: 0.08em;
  color: var(--muted);
}

/* ---------- 墨绿数据带 ---------- */

.page-about .about-board {
  position: relative;
  overflow: hidden;
  margin-top: 1.6rem;
  padding: clamp(2.4rem, 6vw, 4.2rem) 0;
  background: var(--ink);
  color: var(--canvas);
}

.page-about .about-board::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(120% 150% at 10% -20%, rgba(192, 138, 62, 0.24), transparent 58%);
  pointer-events: none;
}

.page-about .about-board__grid {
  position: relative;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.5rem 1.2rem;
}

.page-about .about-stat {
  padding-left: 1rem;
  border-left: 2px solid rgba(232, 185, 106, 0.42);
}

.page-about .about-stat__value {
  display: block;
  font-family: var(--mono);
  font-size: clamp(2.1rem, 6.4vw, 3.2rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--copper-hi);
}

.page-about .about-stat__value small {
  margin-left: 0.12em;
  font-size: 0.42em;
  letter-spacing: 0;
}

.page-about .about-stat__label {
  display: block;
  margin-top: 0.65rem;
  font-size: 0.82rem;
  line-height: 1.7;
  color: rgba(244, 242, 236, 0.66);
}

/* ---------- 分栏骨架 ---------- */

.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 2rem;
  padding: clamp(2.4rem, 6vw, 3.8rem) 0 clamp(3rem, 8vw, 5rem);
}

.page-about .about-rail {
  min-width: 0;
}

.page-about .about-rail__label {
  margin: 0 0 0.8rem;
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .about-rail__list {
  display: flex;
  gap: 0.5rem;
  margin: 0;
  padding: 0 0 0.6rem;
  list-style: none;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-rail__item {
  flex: none;
}

.page-about .about-rail__link {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
  padding: 0.5rem 0.9rem;
  border: 1px solid var(--line-soft);
  border-radius: 999px;
  white-space: nowrap;
  text-decoration: none;
  color: var(--muted);
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease), background-color 0.18s var(--ease);
}

.page-about .about-rail__link:hover {
  color: var(--graphite);
  border-color: rgba(192, 138, 62, 0.5);
}

.page-about .about-rail__num {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  color: var(--copper);
}

.page-about .about-rail__text {
  font-size: 0.84rem;
}

/* ---------- 章节 ---------- */

.page-about .about-flow > * + * {
  margin-top: clamp(2.8rem, 7vw, 4.6rem);
}

.page-about .about-stage {
  scroll-margin-top: 120px;
}

.page-about .about-stage__head {
  display: flex;
  align-items: baseline;
  gap: 0.9rem;
  margin-bottom: 1.3rem;
}

.page-about .about-stage__num {
  flex: none;
  font-family: var(--mono);
  font-size: 0.8rem;
  letter-spacing: 0.16em;
  color: var(--copper);
}

.page-about .about-stage__title {
  margin: 0;
  font-size: clamp(1.35rem, 3.6vw, 1.9rem);
  font-weight: 900;
  line-height: 1.34;
  letter-spacing: -0.016em;
  color: var(--graphite);
}

.page-about .about-prose p {
  margin: 0;
  font-size: 1rem;
  line-height: 1.9;
  color: var(--graphite);
}

.page-about .about-prose p + p {
  margin-top: 1.1rem;
}

/* ---------- 数字胶囊 ---------- */

.page-about .about-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
  margin: 1.5rem 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-chips li {
  display: inline-flex;
  align-items: baseline;
  gap: 0.4rem;
  padding: 0.5rem 0.95rem;
  border-radius: 999px;
  background: var(--paper);
  font-size: 0.85rem;
  color: var(--graphite);
}

.page-about .about-chips__k {
  font-family: var(--mono);
  font-weight: 700;
  color: var(--ink);
}

/* ---------- 图片 ---------- */

.page-about .about-figure {
  margin: 1.8rem 0 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: var(--r-lg);
  object-fit: cover;
}

.page-about .about-figure--square img {
  max-height: 460px;
}

.page-about .about-figure figcaption {
  margin-top: 0.75rem;
  font-family: var(--mono);
  font-size: 0.76rem;
  letter-spacing: 0.05em;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 调度拓扑图 ---------- */

.page-about .about-net-wrap {
  margin-top: 1.8rem;
  padding: clamp(0.9rem, 3vw, 1.8rem);
  border-radius: var(--r-lg);
  background: var(--ink);
}

.page-about .about-net {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .about-net circle,
.page-about .about-net rect {
  transition: opacity 0.2s var(--ease), stroke-width 0.2s var(--ease);
}

.page-about .about-net circle:hover,
.page-about .about-net rect:hover {
  opacity: 0.82;
  stroke-width: 3;
}

/* ---------- 四状态轨道 ---------- */

.page-about .about-track {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1rem;
  margin: 1.8rem 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-track__item {
  position: relative;
  padding: 1.15rem 1rem 1.25rem;
  border-radius: var(--r-md);
  background: var(--canvas);
  box-shadow: inset 0 0 0 1px var(--line-soft);
}

.page-about .about-track__item::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  border-radius: var(--r-md) var(--r-md) 0 0;
  background: var(--copper);
}

.page-about .about-track__item--done::before {
  background: var(--mint);
}

.page-about .about-track__num {
  display: block;
  margin-bottom: 0.5rem;
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.14em;
  color: var(--copper);
}

.page-about .about-track__name {
  display: block;
  margin-bottom: 0.35rem;
  font-size: 1.02rem;
  color: var(--graphite);
}

.page-about .about-track__desc {
  display: block;
  font-size: 0.82rem;
  line-height: 1.72;
  color: var(--muted);
}

/* ---------- 数据卡 ---------- */

.page-about .about-metrics {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 1rem;
  margin-top: 1.8rem;
}

.page-about .about-metric {
  padding: 1.2rem 1.2rem 1.3rem;
  border-radius: var(--r-md);
  background: var(--canvas);
  box-shadow: inset 0 0 0 1px var(--line-soft);
  transition: box-shadow 0.2s var(--ease), transform 0.2s var(--ease);
}

.page-about .about-metric__value {
  display: block;
  font-family: var(--mono);
  font-size: clamp(2rem, 5.4vw, 2.8rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--copper);
}

.page-about .about-metric__value small {
  margin-left: 0.1em;
  font-size: 0.42em;
  color: var(--muted);
}

.page-about .about-metric__label {
  display: block;
  margin-top: 0.55rem;
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--graphite);
}

.page-about .about-metric__detail {
  margin: 0.6rem 0 0;
  font-size: 0.82rem;
  line-height: 1.72;
  color: var(--muted);
}

.page-about .about-metric:hover {
  box-shadow: inset 0 0 0 1px rgba(192, 138, 62, 0.65), var(--shadow-soft);
  transform: translateY(-2px);
}

/* ---------- 合规清单 ---------- */

.page-about .about-legal {
  margin-top: 1.8rem;
  padding: clamp(1.3rem, 4vw, 2.2rem);
  border-radius: var(--r-lg);
  background: var(--paper);
}

.page-about .about-legal__list {
  margin: 0;
}

.page-about .about-legal__row {
  display: grid;
  gap: 0.3rem;
  padding: 0.95rem 0;
  border-bottom: 1px solid rgba(28, 31, 29, 0.1);
}

.page-about .about-legal__row:first-child {
  padding-top: 0;
}

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

.page-about .about-legal__row dt {
  font-family: var(--mono);
  font-size: 0.76rem;
  letter-spacing: 0.12em;
  color: var(--copper);
}

.page-about .about-legal__row dd {
  margin: 0;
  font-size: 0.94rem;
  line-height: 1.82;
  color: var(--graphite);
}

.page-about .about-legal__row dd .copy-btn {
  margin-left: 0.5rem;
  vertical-align: baseline;
}

/* ---------- 收尾 ---------- */

.page-about .about-cta {
  padding: clamp(2.6rem, 7vw, 4.4rem) 0;
  background: var(--ink);
  color: var(--canvas);
}

.page-about .about-cta__eyebrow {
  margin: 0 0 0.9rem;
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--copper-hi);
}

.page-about .about-cta__title {
  margin: 0 0 1rem;
  max-width: 20ch;
  font-size: clamp(1.5rem, 4.4vw, 2.4rem);
  font-weight: 900;
  line-height: 1.28;
  letter-spacing: -0.018em;
  color: var(--canvas);
}

.page-about .about-cta__text {
  margin: 0;
  max-width: 56ch;
  font-size: 1rem;
  line-height: 1.9;
  color: rgba(244, 242, 236, 0.72);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.7rem;
}

.page-about .about-cta__ghost {
  color: var(--copper-hi);
  border-color: rgba(232, 185, 106, 0.55);
  background: transparent;
}

.page-about .about-cta__extra {
  margin: 1.4rem 0 0;
  font-size: 0.86rem;
  line-height: 1.8;
  color: rgba(244, 242, 236, 0.56);
}

.page-about .about-cta__extra a {
  color: var(--copper-hi);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- 桌面布局 ---------- */

@media (min-width: 760px) {
  .page-about .about-board__grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 1.6rem;
  }
}

@media (min-width: 1000px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: clamp(2.4rem, 5vw, 4.2rem);
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: 112px;
  }

  .page-about .about-rail__list {
    display: block;
    padding-bottom: 0;
    overflow: visible;
  }

  .page-about .about-rail__item + .about-rail__item {
    margin-top: 0.15rem;
  }

  .page-about .about-rail__link {
    padding: 0.55rem 0 0.55rem 1rem;
    border: 0;
    border-left: 3px solid var(--line-soft);
    border-radius: 0;
    white-space: normal;
  }

  .page-about .about-rail__link:hover,
  .page-about .about-rail__link.is-active {
    border-left-color: var(--copper);
    color: var(--graphite);
    font-weight: 600;
  }

  .page-about .about-net-wrap {
    padding: 2rem;
  }
}

/* ---------- 动效降级 ---------- */

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__link,
  .page-about .about-metric,
  .page-about .about-net circle,
  .page-about .about-net rect {
    transition: none;
  }

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