.page-about {
  --stage-pad: clamp(20px, 2.8vw, 34px);
  --hairline: rgba(11, 33, 54, 0.14);
  --hairline-dark: rgba(198, 210, 221, 0.2);
  background: var(--paper);
  color: var(--ink);
  padding-bottom: clamp(48px, 7vw, 96px);
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumbs {
  margin-bottom: clamp(18px, 2.6vw, 30px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  border-radius: var(--r-xl);
  padding: clamp(26px, 4.4vw, 56px);
  background:
    radial-gradient(115% 130% at 86% 6%, rgba(94, 211, 192, 0.17), transparent 60%),
    radial-gradient(90% 110% at 6% 96%, rgba(47, 123, 181, 0.24), transparent 62%),
    var(--c-deep);
  color: var(--c-mist);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(198, 210, 221, 0.07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(198, 210, 221, 0.07) 1px, transparent 1px);
  background-size: 58px 58px;
  -webkit-mask-image: radial-gradient(125% 105% at 18% 0%, #000 0%, transparent 76%);
  mask-image: radial-gradient(125% 105% at 18% 0%, #000 0%, transparent 76%);
}

.page-about .about-hero__inner {
  position: relative;
  display: grid;
  gap: clamp(26px, 3.6vw, 46px);
  align-items: center;
}

.page-about .about-hero__eyebrow {
  margin: 0 0 18px;
  font-size: 11px;
  letter-spacing: 0.22em;
  color: var(--c-lime);
}

.page-about .about-hero h1 {
  margin: 0 0 20px;
  font-size: clamp(29px, 5.2vw, 58px);
  line-height: 1.14;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: #ffffff;
  max-width: 20ch;
}

.page-about .about-hero__lead {
  margin: 0 0 30px;
  font-size: clamp(15px, 1.15vw, 17px);
  line-height: 1.86;
  color: var(--c-silver);
  max-width: 48ch;
}

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

.page-about .about-hero .btn-ghost {
  border-color: rgba(198, 210, 221, 0.38);
  color: var(--c-mist);
}

.page-about .about-hero__visual {
  border-radius: var(--r-lg);
  overflow: hidden;
  border: 1px solid var(--hairline-dark);
  background: rgba(19, 44, 69, 0.55);
}

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

/* ---------- 分屏主体 ---------- */
.page-about .about-body {
  display: grid;
  gap: clamp(22px, 3vw, 46px);
  align-items: start;
  min-width: 0;
}

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

.page-about .about-rail__eyebrow {
  margin: 0 0 12px;
  font-size: 10px;
  letter-spacing: 0.24em;
  color: var(--c-slate);
}

.page-about .about-rail__nav {
  display: flex;
  flex-direction: row;
  gap: 8px;
  overflow-x: auto;
  padding: 0 0 12px;
  border-bottom: 1px solid var(--hairline);
  scrollbar-width: thin;
}

.page-about .about-rail .rail-link {
  display: flex;
  align-items: baseline;
  gap: 9px;
  flex: 0 0 auto;
  white-space: nowrap;
  padding: 8px 13px;
  border-radius: var(--r-pill);
  font-size: 13.5px;
  line-height: 1.5;
  color: var(--ink-soft);
  text-decoration: none;
  transition: background-color var(--dur-fast) var(--ease), color var(--dur-fast) var(--ease);
}

.page-about .about-rail .rail-link:hover {
  background: var(--c-mist);
  color: var(--ink);
}

.page-about .about-rail .rail-link[aria-current="true"] {
  background: var(--c-deep);
  color: var(--c-lime);
}

.page-about .about-rail .rail-link[aria-current="true"] .rail-index {
  color: var(--c-lime);
}

.page-about .about-rail .rail-index {
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--c-slate);
}

/* ---------- 阶段流 ---------- */
.page-about .about-stream {
  display: flex;
  flex-direction: column;
  gap: clamp(16px, 2.2vw, 24px);
  min-width: 0;
}

.page-about .stage {
  position: relative;
  display: grid;
  gap: clamp(14px, 2vw, 24px);
  padding: var(--stage-pad);
  border: 1px solid var(--hairline);
  border-radius: var(--r-lg);
  background: var(--c-ivory);
  scroll-margin-top: calc(var(--header-h) + 28px);
  transition: background-color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .stage:target {
  border-color: rgba(163, 230, 53, 0.75);
  background: var(--c-mist);
}

.page-about .stage__head {
  display: flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
}

.page-about .stage__num {
  flex: none;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--c-slate);
  padding: 4px 10px;
  border: 1px solid var(--hairline);
  border-radius: var(--r-pill);
  background: var(--paper);
}

.page-about .stage__title {
  margin: 0;
  font-size: clamp(18px, 2.3vw, 23px);
  line-height: 1.38;
  font-weight: 700;
  color: var(--ink);
}

.page-about .stage__body {
  display: flex;
  flex-direction: column;
  gap: 14px;
  min-width: 0;
}

.page-about .stage__body p {
  margin: 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink-soft);
  max-width: 70ch;
}

.page-about .stage__metric {
  display: inline-flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 10px;
  align-self: flex-start;
  max-width: 100%;
  margin-top: 2px;
  padding: 12px 20px;
  border-radius: var(--r-md);
  background: var(--c-midnight);
  color: var(--c-mist);
}

.page-about .stage__metric-num {
  font-size: clamp(22px, 2.6vw, 28px);
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--c-lime);
}

.page-about .stage__metric-label {
  font-size: 13px;
  line-height: 1.55;
  color: var(--c-silver);
}

.page-about .stage__figure {
  margin: 2px 0 0;
  border-radius: var(--r-md);
  overflow: hidden;
  border: 1px solid var(--hairline);
  background: var(--paper-alt);
}

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

/* ---------- 收尾行动区 ---------- */
.page-about .about-cta {
  margin-top: clamp(40px, 6vw, 84px);
  padding: clamp(28px, 4.2vw, 52px);
  border-radius: var(--r-xl);
  background: linear-gradient(135deg, var(--c-midnight) 0%, var(--c-deep) 62%, var(--c-abyss) 100%);
  color: var(--c-mist);
  display: grid;
  gap: 16px;
}

.page-about .about-cta h2 {
  margin: 0;
  font-size: clamp(22px, 3vw, 34px);
  line-height: 1.28;
  font-weight: 800;
  color: #ffffff;
}

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

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 6px;
}

.page-about .about-cta .btn-ghost {
  border-color: rgba(198, 210, 221, 0.38);
  color: var(--c-mist);
}

/* ---------- 断点 ---------- */
@media (min-width: 760px) {
  .page-about .stage {
    grid-template-columns: minmax(148px, 0.72fr) minmax(0, 1.75fr);
    align-items: start;
  }

  .page-about .stage__head {
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
  }
}

@media (min-width: 1080px) {
  .page-about .about-body {
    grid-template-columns: var(--rail-w) minmax(0, 1fr);
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + 28px);
  }

  .page-about .about-rail__nav {
    flex-direction: column;
    gap: 4px;
    overflow-x: visible;
    padding: 0 0 0 14px;
    border-bottom: 0;
    border-left: 1px solid var(--hairline);
  }

  .page-about .about-rail .rail-link {
    white-space: normal;
    border-radius: var(--r-sm);
    font-size: 14px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .stage,
  .page-about .about-rail .rail-link {
    transition: none;
  }
}
<<<END>>>