.page-about {
  --about-soft: rgba(16, 20, 24, 0.72);
  --about-faint: rgba(16, 20, 24, 0.56);
  --about-card: #FCFAF4;
  --about-line: rgba(16, 20, 24, 0.13);
  --about-glow: rgba(201, 162, 39, 0.2);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding-block: clamp(1.25rem, 3.5vw, 2rem) clamp(2.5rem, 6vw, 4.5rem);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--gold), transparent);
  opacity: 0.45;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: -58%;
  width: min(1100px, 135%);
  aspect-ratio: 1 / 0.44;
  transform: translateX(-50%);
  background: radial-gradient(ellipse at center, var(--about-glow), transparent 68%);
  pointer-events: none;
}

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

.page-about .about-hero .breadcrumbs {
  margin-bottom: clamp(1.4rem, 3.5vw, 2.4rem);
}

.page-about .about-hero .display-1 {
  max-width: 20ch;
  margin-block: 0.8rem 1.1rem;
  text-wrap: balance;
}

.page-about .about-hero .lede {
  max-width: 62ch;
  margin: 0;
  color: var(--mist);
}

.page-about .hero-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(1.75rem, 4.5vw, 2.6rem) 0 0;
  padding: 0;
  background: var(--line-dark);
  border: 1px solid var(--line-dark);
}

.page-about .hero-stats > div {
  background: rgba(8, 23, 42, 0.6);
  padding: 0.9rem 1rem 1.05rem;
}

.page-about .hero-stats dt {
  margin: 0;
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--mist);
  line-height: 1.5;
}

.page-about .hero-stats dd {
  margin: 0.4rem 0 0;
  font-family: var(--font-mono);
  font-size: clamp(1.15rem, 3.2vw, 1.6rem);
  letter-spacing: 0.04em;
  color: var(--gold);
  line-height: 1.3;
}

/* ---------- 主体骨架 ---------- */
.page-about .about-body {
  padding-block: clamp(2.25rem, 5.5vw, 4rem) clamp(2.75rem, 6.5vw, 5rem);
}

.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1.75rem, 4.5vw, 3.25rem);
  align-items: start;
}

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

/* ---------- 锚点侧栏 ---------- */
.page-about .about-rail {
  align-self: start;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--about-line);
}

.page-about .rail-title {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  margin: 0 0 0.75rem;
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--gold-deep);
}

.page-about .rail-title::before {
  content: "";
  width: 18px;
  height: 1px;
  background: var(--gold);
  flex: none;
}

.page-about .about-rail nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.15rem 1.1rem;
}

.page-about .rail-link {
  display: block;
  padding: 0.35rem 0;
  font-size: 14.5px;
  line-height: 1.45;
  color: var(--about-faint);
  text-decoration: none;
  border-left: 2px solid transparent;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

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

.page-about .rail-link[aria-current="true"] {
  color: var(--ink);
  border-left-color: var(--gold);
  font-weight: 500;
}

/* ---------- 章节通用 ---------- */
.page-about .about-section {
  padding-block: clamp(1.75rem, 4.5vw, 2.9rem);
  border-top: 1px solid var(--about-line);
}

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

.page-about .sec-head {
  margin-bottom: clamp(1.25rem, 3.2vw, 2rem);
}

.page-about .sec-head h2 {
  margin: 0 0 0.7rem;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.4rem, 3.6vw, 2rem);
  line-height: 1.3;
  letter-spacing: -0.01em;
  max-width: 24ch;
  color: var(--ink);
}

.page-about .sec-head p:not(.eyebrow) {
  margin: 0;
  max-width: 64ch;
  font-size: 16px;
  line-height: 1.8;
  color: var(--about-soft);
}

/* ---------- 阶段档案卡 ---------- */
.page-about .origin-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1.5rem, 4vw, 2.5rem);
  align-items: start;
}

.page-about .origin-main {
  min-width: 0;
}

.page-about .stage-card {
  position: relative;
  padding: clamp(1.05rem, 2.6vw, 1.5rem);
  margin-bottom: 0.9rem;
  background: var(--about-card);
  border: 1px solid var(--about-line);
  border-left: 3px solid var(--paper-dim);
  transition: border-color 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.page-about .stage-card:last-child {
  margin-bottom: 0;
}

.page-about .stage-card:hover {
  border-left-color: var(--gold);
  box-shadow: 0 8px 22px rgba(16, 20, 24, 0.07);
}

.page-about .stage-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.45rem 0.8rem;
  margin-bottom: 0.75rem;
}

.page-about .stage-no {
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--gold-deep);
}

.page-about .stage-title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.05rem, 2.4vw, 1.28rem);
  line-height: 1.42;
  color: var(--ink);
}

.page-about .stage-card > p {
  margin: 0;
  max-width: 62ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--about-soft);
}

.page-about .fold {
  margin-top: 0.85rem;
  padding-top: 0.65rem;
  border-top: 1px dashed var(--about-line);
}

.page-about .fold > summary {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  cursor: pointer;
  list-style: none;
  font-size: 14px;
  font-weight: 500;
  color: var(--gold-deep);
}

.page-about .fold > summary::-webkit-details-marker {
  display: none;
}

.page-about .fold > summary::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 15px;
  line-height: 1;
  color: var(--gold);
}

.page-about .fold[open] > summary::after {
  content: "–";
}

.page-about .fold > .fold-body {
  padding-top: 0.6rem;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--about-faint);
}

.page-about .origin-side {
  min-width: 0;
}

.page-about .origin-figure {
  margin: 0 0 0.9rem;
}

.page-about .origin-side .note {
  margin: 0;
  max-width: 42ch;
}

/* ---------- 团队 ---------- */
.page-about .team-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1.25rem, 3.5vw, 2.25rem);
  align-items: start;
}

.page-about .team-copy p {
  margin: 0 0 1rem;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--about-soft);
}

.page-about .team-copy p:last-child {
  margin-bottom: 0;
}

.page-about .team-figures ul {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--about-line);
}

.page-about .team-figures li {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.2rem;
  padding: 0.85rem 0;
  border-bottom: 1px solid var(--about-line);
}

.page-about .fig-key {
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--gold-deep);
}

.page-about .fig-val {
  font-size: 15px;
  line-height: 1.7;
  color: var(--about-soft);
}

/* ---------- 方法论 ---------- */
.page-about .method-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1.5rem, 4vw, 2.5rem);
  align-items: start;
}

.page-about .method-steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.9rem;
}

.page-about .method-steps li {
  position: relative;
  padding: 1.15rem 1.1rem 1.2rem;
  background: var(--about-card);
  border: 1px solid var(--about-line);
}

.page-about .method-steps li::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 34px;
  height: 3px;
  background: var(--gold);
}

.page-about .step-no {
  display: block;
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--gold-deep);
  margin-bottom: 0.35rem;
}

.page-about .method-steps h3 {
  margin: 0 0 0.45rem;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.08rem;
  line-height: 1.4;
  color: var(--ink);
}

.page-about .method-steps p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--about-soft);
}

.page-about .method-figure {
  margin: 0;
}

/* ---------- 版本演进（深色面板） ---------- */
.page-about .version-panel {
  position: relative;
  padding: clamp(1.4rem, 4vw, 2.6rem);
  background: var(--sea);
  border: 1px solid var(--line-dark);
  overflow: hidden;
}

.page-about .version-panel::after {
  content: "";
  position: absolute;
  right: -12%;
  top: -30%;
  width: 55%;
  aspect-ratio: 1;
  background: radial-gradient(circle, rgba(201, 162, 39, 0.14), transparent 68%);
  pointer-events: none;
}

.page-about .version-panel > * {
  position: relative;
  z-index: 1;
}

.page-about .version-panel .eyebrow {
  color: var(--gold);
}

.page-about .version-panel h2 {
  margin: 0.6rem 0 0.7rem;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.35rem, 3.4vw, 1.9rem);
  line-height: 1.3;
  letter-spacing: -0.01em;
  color: var(--paper);
  max-width: 24ch;
}

.page-about .version-intro {
  margin: 0;
  max-width: 62ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--mist);
}

.page-about .version-track {
  list-style: none;
  margin: clamp(1.4rem, 3.5vw, 2rem) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.1rem;
}

.page-about .version-node {
  position: relative;
  padding-left: 1.1rem;
  border-left: 2px solid rgba(201, 162, 39, 0.32);
}

.page-about .version-tag {
  display: block;
  font-size: 13px;
  letter-spacing: 0.12em;
  color: var(--gold);
  margin-bottom: 0.35rem;
}

.page-about .version-node h3 {
  margin: 0 0 0.4rem;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.05rem;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .version-node p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--mist);
}

.page-about .version-more {
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  margin-top: 0;
  transition: max-height 0.3s var(--ease), opacity 0.25s var(--ease), margin-top 0.3s var(--ease);
}

.page-about .version-node:hover .version-more,
.page-about .version-node:focus-within .version-more {
  max-height: 12rem;
  opacity: 1;
  margin-top: 0.6rem;
}

/* ---------- 覆盖范围 ---------- */
.page-about .coverage-figure {
  margin: 0 0 clamp(1.5rem, 3.5vw, 2.25rem);
}

.page-about .coverage-head {
  margin-bottom: clamp(1.25rem, 3vw, 1.75rem);
}

.page-about .coverage-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  padding: 0;
  background: var(--about-line);
  border: 1px solid var(--about-line);
}

.page-about .coverage-stats > div {
  background: var(--about-card);
  padding: 1rem 1.05rem 1.1rem;
}

.page-about .coverage-stats dt {
  margin: 0;
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--about-faint);
}

.page-about .coverage-stats dd {
  margin: 0.4rem 0 0;
  font-family: var(--font-mono);
  font-size: clamp(1.15rem, 3vw, 1.5rem);
  letter-spacing: 0.03em;
  line-height: 1.3;
  color: var(--gold-deep);
}

.page-about .coverage-foot {
  margin: clamp(1.25rem, 3vw, 1.75rem) 0 0;
  max-width: 66ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--about-soft);
}

/* ---------- 合作 ---------- */
.page-about .partner-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.9rem;
}

.page-about .partner-card {
  display: flex;
  flex-direction: column;
  padding: 1.15rem 1.15rem 1.2rem;
  background: var(--about-card);
  border: 1px solid var(--about-line);
  border-top: 3px solid var(--paper-dim);
  transition: border-color 0.2s var(--ease);
}

.page-about .partner-card:hover {
  border-top-color: var(--gold);
}

.page-about .partner-card h3 {
  margin: 0 0 0.5rem;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.08rem;
  line-height: 1.4;
  color: var(--ink);
}

.page-about .partner-card p {
  margin: 0 0 1rem;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--about-soft);
  flex: 1 1 auto;
}

.page-about .partner-link {
  align-self: flex-start;
  font-size: 14px;
  font-weight: 500;
  color: var(--gold-deep);
  text-decoration: none;
  border-bottom: 1px solid rgba(110, 84, 12, 0.35);
  padding-bottom: 1px;
  transition: border-color 0.2s var(--ease), color 0.2s var(--ease);
}

.page-about .partner-link:hover {
  color: var(--ink);
  border-bottom-color: var(--gold);
}

.page-about .partner-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: clamp(1.5rem, 3.5vw, 2rem);
}

/* ---------- 响应式 ---------- */
@media (min-width: 560px) {
  .page-about .method-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

@media (min-width: 780px) {
  .page-about .hero-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

  .page-about .team-grid {
    grid-template-columns: minmax(0, 1.25fr) minmax(0, 0.75fr);
  }

  .page-about .team-figures li {
    grid-template-columns: 7.5rem minmax(0, 1fr);
    gap: 0.9rem;
    align-items: baseline;
  }

  .page-about .version-track {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 1.25rem;
    padding-top: 1.6rem;
  }

  .page-about .version-track::before {
    content: "";
    position: absolute;
    top: 0.55rem;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(to right, var(--gold), rgba(201, 162, 39, 0.14));
  }

  .page-about .version-track {
    position: relative;
  }

  .page-about .version-node {
    padding-left: 0;
    border-left: 0;
  }

  .page-about .version-node::before {
    content: "";
    position: absolute;
    top: -1.05rem;
    left: 0;
    width: 9px;
    height: 9px;
    border-radius: 50%;
    background: var(--gold);
    box-shadow: 0 0 0 4px rgba(201, 162, 39, 0.16);
    transform: translateY(-50%);
  }
}

@media (min-width: 900px) {
  .page-about .origin-layout {
    grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr);
  }

  .page-about .method-layout {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
  }

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

@media (min-width: 1000px) {
  .page-about .about-shell {
    grid-template-columns: 200px minmax(0, 1fr);
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + 24px);
    border-bottom: 0;
  }

  .page-about .about-rail nav {
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 0;
  }

  .page-about .rail-link {
    padding-left: 0.8rem;
  }
}

@media (hover: none) {
  .page-about .version-more {
    max-height: none;
    opacity: 1;
    margin-top: 0.6rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .stage-card,
  .page-about .partner-card,
  .page-about .rail-link,
  .page-about .partner-link,
  .page-about .version-more {
    transition: none;
  }

  .page-about .version-more {
    max-height: none;
    opacity: 1;
    margin-top: 0.6rem;
  }
}
<<<PAGE_CSS_END>>>