.page-about {
  --about-measure: 34em;
  --about-rail-w: 200px;
  background: var(--night);
  color: var(--paper);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding-block: clamp(20px, 4vw, 40px) clamp(40px, 6vw, 72px);
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, var(--line-soft) 1px, transparent 1px),
    linear-gradient(to bottom, var(--line-soft) 1px, transparent 1px);
  background-size: 96px 96px;
  opacity: 0.5;
  pointer-events: none;
  -webkit-mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.85), transparent 88%);
  mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.85), transparent 88%);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 84% 12%, var(--cyan-soft), transparent 58%);
  pointer-events: none;
}

.page-about .about-hero .shell {
  position: relative;
  z-index: 1;
}

.page-about .about-breadcrumbs {
  margin-bottom: clamp(24px, 4vw, 44px);
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.page-about .about-breadcrumbs a {
  color: var(--mist);
  text-decoration: none;
}

.page-about .about-breadcrumbs a:hover,
.page-about .about-breadcrumbs a:focus-visible {
  color: var(--cyan);
}

.page-about .about-breadcrumbs .breadcrumb-item[aria-current="page"] {
  color: var(--paper);
}

.page-about .about-hero-inner {
  display: grid;
  gap: clamp(28px, 4vw, 48px);
}

.page-about .about-title {
  margin: 0 0 0.5em;
  font-family: var(--font-display);
  font-size: clamp(2.15rem, 6vw, 4.4rem);
  line-height: 1.06;
  font-weight: 800;
  letter-spacing: 0.015em;
  color: var(--paper);
}

.page-about .about-title-accent {
  position: relative;
  display: inline-block;
  color: var(--paper);
}

.page-about .about-title-accent::after {
  content: "";
  position: absolute;
  left: -0.06em;
  right: -0.06em;
  bottom: 0.06em;
  height: 0.28em;
  background: var(--cyan);
  opacity: 0.35;
  z-index: -1;
}

.page-about .about-lede {
  max-width: 30em;
  margin: 0 0 1.8em;
  font-size: clamp(1rem, 1.6vw, 1.1rem);
  line-height: 1.85;
  color: var(--mist);
}

.page-about .about-hero-facts {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 32px;
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line-soft);
  padding-top: 20px;
  max-width: 34em;
}

.page-about .about-hero-facts li {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.page-about .about-fact-key {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--mist);
}

.page-about .about-fact-val {
  font-family: var(--font-mono);
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--cyan);
  letter-spacing: 0.01em;
}

.page-about .about-dossier {
  padding: clamp(20px, 3vw, 28px);
  border: 1px solid var(--line);
  border-left: 2px solid var(--cyan);
  border-radius: var(--radius);
}

.page-about .about-dossier-kicker {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--mist);
}

.page-about .about-dossier-code {
  margin: 0 0 20px;
  font-family: var(--font-mono);
  font-size: clamp(1.15rem, 2.4vw, 1.5rem);
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--paper);
}

.page-about .about-dossier-meta {
  margin: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-dossier-row {
  display: grid;
  grid-template-columns: 4.6em minmax(0, 1fr);
  gap: 12px;
  align-items: baseline;
  padding-top: 12px;
  border-top: 1px solid var(--line-soft);
}

.page-about .about-dossier-row dt {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  color: var(--mist);
}

.page-about .about-dossier-row dd {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.6;
  color: var(--paper);
}

.page-about .about-hero-media {
  margin: clamp(28px, 4vw, 52px) 0 0;
}

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

/* ---------- 主体骨架 ---------- */
.page-about .about-body {
  display: grid;
  gap: clamp(28px, 4vw, 48px);
  padding-block: clamp(40px, 6vw, 88px) clamp(56px, 8vw, 104px);
}

.page-about .about-rail-title {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--mist);
}

.page-about .about-rail-list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 8px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-rail-link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 8px 14px;
  min-height: 44px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  font-size: 0.9rem;
  color: var(--mist);
  text-decoration: none;
  white-space: nowrap;
  transition: color 180ms ease, border-color 180ms ease, background-color 180ms ease;
}

.page-about .about-rail-num {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  color: var(--deep-teal);
}

.page-about .about-rail-link:hover,
.page-about .about-rail-link:focus-visible {
  color: var(--paper);
  border-color: var(--cyan);
  background: var(--cyan-soft);
}

.page-about .about-rail-link:hover .about-rail-num,
.page-about .about-rail-link:focus-visible .about-rail-num {
  color: var(--cyan);
}

.page-about .about-article {
  max-width: 700px;
  min-width: 0;
}

.page-about .about-section + .about-section {
  margin-top: clamp(48px, 7vw, 92px);
  padding-top: clamp(32px, 5vw, 56px);
  border-top: 1px solid var(--line-soft);
}

.page-about .about-section-num {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .about-section-title {
  margin: 0 0 1.1em;
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 3.2vw, 2.1rem);
  line-height: 1.28;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--paper);
}

.page-about .about-article .prose {
  max-width: var(--about-measure);
  color: var(--mist);
}

.page-about .about-article .prose p {
  font-size: clamp(1rem, 1.5vw, 1.05rem);
  line-height: 1.85;
}

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

.page-about .about-quote {
  margin: clamp(24px, 3.5vw, 36px) 0;
  padding: 18px 0 18px 20px;
  border-left: 3px solid var(--cyan);
  max-width: var(--about-measure);
}

.page-about .about-quote p {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(1.15rem, 2.2vw, 1.45rem);
  font-weight: 700;
  letter-spacing: 0.04em;
  line-height: 1.5;
  color: var(--paper);
}

/* ---------- 方法条 ---------- */
.page-about .about-method-grid {
  display: grid;
  gap: 1px;
  margin-top: clamp(24px, 3.5vw, 36px);
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  overflow: hidden;
  max-width: var(--about-measure);
}

.page-about .about-method-item {
  background: var(--glass);
  padding: 18px 20px;
}

.page-about .about-method-key {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--amber);
}

.page-about .about-method-text {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.75;
  color: var(--mist);
}

/* ---------- 内嵌图 ---------- */
.page-about .about-inline-media {
  margin: clamp(24px, 4vw, 40px) 0;
  max-width: var(--about-measure);
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  margin: clamp(24px, 4vw, 40px) 0 0;
  padding: 0;
  list-style: none;
  max-width: var(--about-measure);
}

.page-about .about-timeline .timeline-item {
  position: relative;
  padding: 0 0 clamp(22px, 3vw, 32px) 26px;
  border-left: 1px solid var(--line);
}

.page-about .about-timeline .timeline-item:last-child {
  padding-bottom: 0;
  border-left-color: transparent;
}

.page-about .about-timeline .timeline-mark {
  position: absolute;
  left: -5px;
  top: 6px;
  width: 9px;
  height: 9px;
  display: block;
  background: var(--cyan);
  transform: rotate(45deg);
}

.page-about .about-tl-stage {
  margin: 0 0 4px;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--mist);
}

.page-about .about-tl-title {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-size: clamp(1rem, 1.8vw, 1.14rem);
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--paper);
}

.page-about .about-tl-text {
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.8;
  color: var(--mist);
}

/* ---------- 数据锚点 ---------- */
.page-about .about-stats {
  display: grid;
  gap: 1px;
  margin: clamp(24px, 3.5vw, 36px) 0;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  overflow: hidden;
  max-width: var(--about-measure);
}

.page-about .about-stats .data-figure {
  background: var(--glass);
  padding: 20px;
}

.page-about .about-stats .data-figure-value {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: clamp(1.8rem, 4.4vw, 2.6rem);
  font-weight: 700;
  letter-spacing: 0.02em;
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-stats .data-figure--amber .data-figure-value {
  color: var(--amber);
}

.page-about .about-stats .data-figure-label {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  color: var(--mist);
}

/* ---------- 收尾 ---------- */
.page-about .about-cta {
  margin-top: clamp(48px, 7vw, 92px);
  padding: clamp(28px, 4vw, 44px);
  background: var(--field-black);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  position: relative;
  overflow: hidden;
}

.page-about .about-cta::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 46%;
  height: 2px;
  background: linear-gradient(to right, var(--cyan), var(--amber), transparent);
}

.page-about .about-cta-title {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-size: clamp(1.3rem, 2.8vw, 1.75rem);
  font-weight: 700;
  letter-spacing: 0.03em;
  color: var(--paper);
}

.page-about .about-cta-text {
  margin: 0 0 24px;
  max-width: 30em;
  font-size: 0.95rem;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .about-cta-links {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 18px;
}

/* ---------- 桌面 ---------- */
@media (min-width: 900px) {
  .page-about .about-hero-inner {
    grid-template-columns: minmax(0, 1.4fr) minmax(280px, 0.6fr);
    align-items: start;
    gap: clamp(40px, 6vw, 96px);
  }

  .page-about .about-hero-aside {
    margin-top: 44px;
  }

  .page-about .about-body {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: clamp(48px, 7vw, 104px);
    align-items: start;
  }

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

  .page-about .about-rail-list {
    flex-direction: column;
    gap: 2px;
    padding-bottom: 0;
    overflow: visible;
  }

  .page-about .about-rail-link {
    display: grid;
    grid-template-columns: 2.2em minmax(0, 1fr);
    align-items: baseline;
    gap: 8px;
    width: 100%;
    padding: 11px 0 11px 14px;
    border: 0;
    border-left: 1px solid var(--line-soft);
    border-radius: 0;
    min-height: 0;
    background: transparent;
    text-align: left;
  }

  .page-about .about-rail-link:hover,
  .page-about .about-rail-link:focus-visible {
    border-left-color: var(--cyan);
    border-left-width: 2px;
    padding-left: 13px;
    background: transparent;
  }

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

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

@media (min-width: 1180px) {
  .page-about .about-hero-media {
    margin-top: clamp(40px, 5vw, 64px);
  }

  .page-about .about-article {
    max-width: 720px;
  }
}

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