.page-about {
  --about-sec-pad: clamp(48px, 7vw, 96px);
  --about-quote-pad: clamp(56px, 10vw, 128px);
  display: block;
}

.page-about .breadcrumbs {
  margin: 18px 0 4px;
  font-size: 13px;
  color: var(--muted);
}

.page-about .breadcrumbs a {
  color: var(--muted);
  text-decoration: none;
  transition: color .16s var(--ease);
}

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

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  display: grid;
  gap: clamp(28px, 4vw, 44px);
  padding-block: clamp(20px, 3vw, 40px) 0;
}

@media (min-width: 960px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, .92fr);
    align-items: stretch;
  }
}

.page-about .about-hero__title {
  font-family: var(--font-display);
  font-weight: 300;
  letter-spacing: -.02em;
  margin: 12px 0 0;
  color: var(--text);
}

.page-about .about-hero__intro {
  max-width: 46ch;
  margin: 24px 0 0;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-hero__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 26px;
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
  font-size: 13px;
  letter-spacing: .04em;
  color: var(--muted);
}

.page-about .about-hero__meta li {
  display: flex;
  align-items: baseline;
  gap: 8px;
}

.page-about .about-hero__meta li::before {
  content: "";
  width: 14px;
  height: 2px;
  background: var(--lg-c);
  border-radius: 2px;
}

.page-about .about-hero__meta .data-num {
  font-size: 15px;
  color: var(--cyan);
}

.page-about .about-hero__sand {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: clamp(24px, 3vw, 34px);
  border-radius: var(--r-lg);
  background: var(--sand);
  color: var(--ink);
  overflow: hidden;
  box-shadow: var(--shadow);
}

.page-about .about-hero__sand::after {
  content: "";
  position: absolute;
  right: -64px;
  bottom: -96px;
  width: 220px;
  height: 220px;
  border-radius: 50%;
  border: 1px solid rgba(6, 18, 15, .16);
  box-shadow: 0 0 0 24px rgba(6, 18, 15, .05);
  pointer-events: none;
}

.page-about .about-hero__sandhead {
  margin: 0;
  font-size: 12px;
  letter-spacing: .14em;
  color: rgba(6, 18, 15, .58);
  position: relative;
  z-index: 1;
}

.page-about .sand-stats {
  margin: 0;
  position: relative;
  z-index: 1;
}

.page-about .sand-stats__row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  padding: 11px 0;
  border-bottom: 1px solid rgba(6, 18, 15, .14);
}

.page-about .sand-stats__row:last-child {
  border-bottom: 0;
}

.page-about .sand-stats dt {
  font-size: 13px;
  color: rgba(6, 18, 15, .66);
}

.page-about .sand-stats dd {
  margin: 0;
  font-size: clamp(20px, 2.4vw, 26px);
  font-weight: 500;
  letter-spacing: .02em;
  color: var(--ink);
}

.page-about .about-hero__sandfoot {
  margin: 0;
  position: relative;
  z-index: 1;
  font-size: 12.5px;
  line-height: 1.7;
  color: rgba(6, 18, 15, .6);
}

/* ---------- 通用标题与图 ---------- */

.page-about .about-sec {
  padding-block: var(--about-sec-pad);
}

.page-about .about-head {
  max-width: 62ch;
  margin-bottom: clamp(24px, 3vw, 36px);
}

.page-about .about-head h2 {
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-weight: 400;
  font-size: clamp(25px, 3.4vw, 40px);
  line-height: 1.2;
  letter-spacing: -.01em;
  color: var(--text);
}

.page-about .about-head__note {
  margin: 14px 0 0;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-fig {
  margin: 0 0 clamp(26px, 3.5vw, 40px);
  border: 1px solid var(--edge);
  border-radius: var(--r-lg);
  overflow: hidden;
  background: var(--panel);
}

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

.page-about .about-fig .media__caption {
  padding: 12px 18px 14px;
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--muted);
  border-top: 1px solid var(--edge);
  background: rgba(12, 35, 29, .62);
}

/* ---------- 纵向时间线 ---------- */

.page-about .tl {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 22px;
}

.page-about .tl::before {
  content: "";
  position: absolute;
  top: 6px;
  bottom: 6px;
  left: 5px;
  width: 1px;
  background: linear-gradient(180deg, transparent, var(--edge) 6%, var(--edge) 94%, transparent);
}

.page-about .tl-node {
  position: relative;
  margin-left: 33px;
  padding: 20px 20px 22px;
  border: 1px solid var(--edge);
  border-radius: var(--r-md);
  background: var(--panel);
  transition: border-color .18s var(--ease), transform .18s var(--ease), background .18s var(--ease);
}

.page-about .tl-node::before {
  content: "";
  position: absolute;
  left: -34px;
  top: 25px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--lg-c);
  box-shadow: 0 0 0 4px var(--ink);
  transition: background .18s var(--ease);
}

.page-about .tl-node:hover,
.page-about .tl-node:focus-within {
  border-color: var(--cyan);
  transform: translateY(-3px);
  background: rgba(12, 35, 29, .95);
}

.page-about .tl-node:hover::before,
.page-about .tl-node:focus-within::before {
  background: var(--cyan);
}

.page-about .tl-node__year {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin: 0 0 10px;
}

.page-about .tl-node__year .data-num {
  font-size: clamp(23px, 3vw, 31px);
  color: var(--cyan);
  letter-spacing: .04em;
}

.page-about .tl-node__era {
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--muted);
}

.page-about .tl-node__title {
  margin: 0 0 10px;
  font-size: clamp(17px, 1.9vw, 20px);
  font-weight: 500;
  line-height: 1.45;
  color: var(--text);
}

.page-about .tl-node__text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .tl-node__solved {
  display: inline-block;
  margin: 14px 0 0;
  padding: 4px 12px;
  border: 1px solid rgba(255, 138, 60, .38);
  border-radius: 999px;
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--orange);
}

@media (min-width: 900px) {
  .page-about .tl::before {
    left: 50%;
    transform: translateX(-.5px);
  }

  .page-about .tl-node {
    margin-left: 0;
  }

  .page-about .tl-node:nth-child(odd) {
    margin-right: calc(50% + 34px);
  }

  .page-about .tl-node:nth-child(even) {
    margin-left: calc(50% + 34px);
  }

  .page-about .tl-node:nth-child(odd)::before {
    left: auto;
    right: -40px;
  }

  .page-about .tl-node:nth-child(even)::before {
    left: -40px;
  }
}

/* ---------- 引述呼吸点 ---------- */

.page-about .about-quote {
  position: relative;
  padding-block: var(--about-quote-pad);
  text-align: center;
}

.page-about .about-quote::before {
  content: "";
  position: absolute;
  left: 50%;
  top: 0;
  width: 1px;
  height: 44px;
  transform: translateX(-50%);
  background: linear-gradient(180deg, transparent, var(--edge));
}

.page-about .about-quote__text {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(26px, 5vw, 56px);
  line-height: 1.26;
  letter-spacing: -.015em;
  color: var(--text);
}

.page-about .about-quote__text span {
  color: var(--cyan);
}

/* ---------- 四环节 ---------- */

.page-about .about-flow__layout {
  display: grid;
  gap: clamp(26px, 3.5vw, 40px);
}

.page-about .flow {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

@media (min-width: 720px) {
  .page-about .flow {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.page-about .flow__card {
  padding: 22px 22px 20px;
  border: 1px solid var(--edge);
  border-radius: var(--r-md);
  background: linear-gradient(160deg, rgba(12, 35, 29, .92), rgba(6, 18, 15, .62));
  transition: transform .18s var(--ease), border-color .18s var(--ease), opacity .18s var(--ease);
}

.page-about .flow:hover .flow__card:not(:hover) {
  opacity: .6;
}

.page-about .flow__card:hover,
.page-about .flow__card:focus-within {
  transform: translateY(-4px);
  border-color: var(--cyan);
  opacity: 1;
}

.page-about .flow__idx {
  display: block;
  font-size: 13px;
  letter-spacing: .12em;
  color: var(--cyan);
}

.page-about .flow__card h3 {
  margin: 10px 0 10px;
  font-size: 17px;
  font-weight: 500;
  color: var(--text);
}

.page-about .flow__card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .flow__card .flow__catch {
  margin: 14px 0 0;
  padding-top: 12px;
  border-top: 1px dashed rgba(255, 138, 60, .28);
  font-size: 12.5px;
  letter-spacing: .02em;
  color: var(--orange);
}

@media (min-width: 1000px) {
  .page-about .about-flow__layout {
    grid-template-columns: minmax(0, 1.42fr) minmax(0, .58fr);
    align-items: start;
  }

  .page-about .about-flow__fig {
    position: sticky;
    top: calc(var(--topbar-h) + 24px);
    margin-bottom: 0;
  }
}

/* ---------- 覆盖范围 ---------- */

.page-about .scope {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .scope__row {
  display: grid;
  grid-template-columns: 6px minmax(0, 1fr);
  gap: 0 18px;
  padding: 18px 20px;
  border: 1px solid var(--edge);
  border-radius: var(--r-sm);
  background: rgba(12, 35, 29, .55);
  transition: border-color .18s var(--ease), background .18s var(--ease);
}

.page-about .scope__row:hover {
  border-color: var(--lg-c);
  background: rgba(12, 35, 29, .82);
}

.page-about .scope__stripe {
  display: block;
  width: 6px;
  height: 100%;
  min-height: 46px;
  border-radius: 999px;
}

.page-about .scope__body h3 {
  margin: 0 0 8px;
  font-size: 16.5px;
  font-weight: 500;
  color: var(--text);
}

.page-about .scope__body p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .scope__foot {
  margin-top: 20px;
  display: grid;
  gap: 16px;
  padding: 20px 22px;
  border: 1px dashed var(--edge);
  border-radius: var(--r-md);
  background: rgba(23, 64, 52, .18);
}

.page-about .scope__foot p {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .scope__foot span {
  color: var(--text);
}

@media (min-width: 820px) {
  .page-about .scope__foot {
    grid-template-columns: 1fr 1fr;
    gap: 30px;
  }
}

/* ---------- 团队与轮值 ---------- */

.page-about .team {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(108px, 1fr));
  gap: 14px;
  margin-bottom: 22px;
}

.page-about .team__stat {
  padding: 18px 16px;
  border: 1px solid var(--edge);
  border-radius: var(--r-sm);
  background: rgba(12, 35, 29, .6);
}

.page-about .team__num {
  margin: 0;
  font-size: clamp(28px, 3.6vw, 40px);
  line-height: 1;
  letter-spacing: .02em;
  color: var(--cyan);
}

.page-about .team__label {
  margin: 10px 0 0;
  font-size: 12.5px;
  letter-spacing: .08em;
  color: var(--muted);
}

.page-about .team__rota {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .team__shift {
  padding: 20px;
  border: 1px solid var(--edge);
  border-radius: var(--r-md);
  background: linear-gradient(180deg, rgba(23, 64, 52, .3), rgba(6, 18, 15, .22));
  transition: border-color .18s var(--ease);
}

.page-about .team__shift:hover {
  border-color: var(--lg-c);
}

.page-about .team__shift-tag {
  margin: 0 0 10px;
  font-size: 12.5px;
  letter-spacing: .1em;
  color: var(--lg-c);
}

.page-about .team__shift p:last-child {
  margin: 0;
  font-size: 14px;
  line-height: 1.82;
  color: var(--muted);
}

@media (min-width: 800px) {
  .page-about .team__rota {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 联系方式入口 ---------- */

.page-about .reach {
  display: grid;
  gap: 14px;
}

.page-about .reach__card {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 24px 22px;
}

.page-about .reach__card h3 {
  margin: 0;
  font-size: 16.5px;
  font-weight: 500;
  color: var(--text);
}

.page-about .reach__card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.82;
  color: var(--muted);
}

.page-about .reach__card .btn {
  align-self: flex-start;
  margin-top: auto;
}

@media (min-width: 820px) {
  .page-about .reach {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 结尾 ---------- */

.page-about .about-cta {
  padding-block: clamp(20px, 3vw, 32px) clamp(48px, 7vw, 88px);
}

.page-about .about-cta__inner {
  padding: clamp(28px, 4vw, 52px);
  border: 1px solid var(--edge);
  border-radius: var(--r-lg);
  background:
    radial-gradient(120% 140% at 100% 0%, rgba(44, 224, 198, .14), transparent 56%),
    linear-gradient(160deg, var(--panel), var(--ink));
}

.page-about .about-cta__inner h2 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(24px, 3.4vw, 38px);
  line-height: 1.24;
  letter-spacing: -.01em;
  color: var(--text);
}

.page-about .about-cta__inner p {
  max-width: 56ch;
  margin: 14px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

/* ---------- 窄屏收尾 ---------- */

@media (max-width: 640px) {
  .page-about .about-hero__meta {
    gap: 8px 18px;
  }

  .page-about .tl-node {
    padding: 18px 16px 18px;
  }

  .page-about .scope__row {
    padding: 16px 16px;
    gap: 0 14px;
  }

  .page-about .about-cta__actions .btn {
    width: 100%;
    text-align: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .tl-node,
  .page-about .flow__card,
  .page-about .scope__row,
  .page-about .team__shift,
  .page-about .breadcrumbs a {
    transition: none;
  }

  .page-about .tl-node:hover,
  .page-about .tl-node:focus-within,
  .page-about .flow__card:hover,
  .page-about .flow__card:focus-within {
    transform: none;
  }

  .page-about .flow:hover .flow__card:not(:hover) {
    opacity: 1;
  }
}
<<<END>>>