.page-about {
  --about-rail: 196px;
  --about-gap: clamp(1.5rem, 4vw, 3.75rem);
  display: block;
  padding-bottom: clamp(2.5rem, 6vw, 5rem);
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumbs {
  padding-block: 1.25rem .5rem;
}
.page-about .crumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .45rem;
  margin: 0;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: .76rem;
  letter-spacing: .08em;
  color: var(--c-steel);
}
.page-about .crumb-list a {
  color: var(--c-ice);
  text-decoration: none;
}
.page-about .crumb-list a:hover {
  text-decoration: underline;
}
.page-about .crumb-list li + li::before {
  content: "/";
  margin-right: .45rem;
  color: var(--c-line);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(1.5rem, 4vw, 3rem);
  padding-block: 1.75rem 1.5rem;
  border-bottom: 1px solid var(--c-line-soft);
}
.page-about .about-hero h1 {
  margin: .55rem 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.85rem, 5.4vw, 3.05rem);
  line-height: 1.08;
  letter-spacing: .005em;
  color: var(--c-bright);
  text-wrap: balance;
}
.page-about .about-hero .lede {
  margin: 1rem 0 0;
  max-width: 46ch;
  font-size: clamp(.95rem, 1.6vw, 1.03rem);
  line-height: 1.78;
  color: var(--c-text-dim);
}
.page-about .about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: .6rem;
  margin-top: 1.5rem;
}
.page-about .about-hero-visual {
  position: relative;
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  padding: clamp(.9rem, 2.5vw, 1.5rem);
  background:
    linear-gradient(180deg, var(--c-glass), transparent 68%),
    repeating-linear-gradient(0deg, var(--c-line-soft) 0 1px, transparent 1px 44px),
    repeating-linear-gradient(90deg, var(--c-line-soft) 0 1px, transparent 1px 44px),
    var(--c-panel);
}
.page-about .about-hero-visual svg {
  display: block;
  width: 100%;
  height: auto;
}

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, .88fr);
    align-items: center;
    padding-block: 3rem 2.25rem;
    gap: clamp(2rem, 5vw, 4rem);
  }
}

/* ---------- 主体两栏骨架 ---------- */
.page-about .about-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--about-gap);
  padding-block: clamp(2rem, 5vw, 3.5rem) 0;
}

.page-about .about-rail .eyebrow {
  margin: 0 0 .6rem;
}
.page-about .about-rail-list {
  display: flex;
  gap: .4rem;
  margin: 0;
  padding: 0 0 .6rem;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
}
.page-about .about-rail-list::-webkit-scrollbar {
  display: none;
}
.page-about .about-rail-list a {
  display: inline-flex;
  align-items: baseline;
  gap: .45rem;
  white-space: nowrap;
  padding: .4rem .7rem;
  border: 1px solid var(--c-line-soft);
  border-radius: var(--radius);
  color: var(--c-text-dim);
  font-size: .84rem;
  text-decoration: none;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}
.page-about .about-rail-list a:hover,
.page-about .about-rail-list a:focus-visible {
  color: var(--c-bright);
  border-color: var(--c-ice);
  background: var(--c-glass);
}
.page-about .about-rail-list .num {
  font-family: var(--font-mono);
  font-size: .76rem;
  color: var(--c-cyan);
}
.page-about .about-rail-coord {
  display: none;
  margin: 1.25rem 0 0;
  padding-top: .9rem;
  border-top: 1px solid var(--c-line-soft);
  font-family: var(--font-mono);
  font-size: .72rem;
  line-height: 1.7;
  letter-spacing: .05em;
  color: var(--c-steel);
}

@media (min-width: 1024px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
  }
  .page-about .about-rail {
    position: sticky;
    top: 6.5rem;
    align-self: start;
    padding-right: 1.25rem;
    border-right: 1px solid var(--c-line-soft);
  }
  .page-about .about-rail-list {
    flex-direction: column;
    overflow: visible;
    padding-bottom: 0;
  }
  .page-about .about-rail-list a {
    display: flex;
    width: 100%;
    border-color: transparent;
    padding-left: .5rem;
    border-left: 2px solid transparent;
    border-radius: 0;
  }
  .page-about .about-rail-list a:hover,
  .page-about .about-rail-list a:focus-visible {
    border-left-color: var(--c-ice);
    background: var(--c-glass);
  }
  .page-about .about-rail-coord {
    display: block;
  }
}

/* ---------- 章节通用 ---------- */
.page-about .about-section {
  padding-block: clamp(1.75rem, 4.5vw, 3rem);
  border-top: 1px solid var(--c-line-soft);
  scroll-margin-top: 6.5rem;
}
.page-about .about-section:first-child {
  border-top: 0;
  padding-top: 0;
}
.page-about .about-section-head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  align-items: baseline;
  gap: .3rem .85rem;
  margin-bottom: 1.35rem;
}
.page-about .about-section-head .section-index {
  font-family: var(--font-mono);
  font-size: clamp(1.5rem, 4vw, 2.35rem);
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--c-ice);
}
.page-about .about-section-head .section-title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.3rem, 3.3vw, 1.95rem);
  line-height: 1.18;
  letter-spacing: .01em;
  color: var(--c-bright);
}
.page-about .about-section-head .section-lede {
  grid-column: 2;
  margin: 0;
  max-width: 62ch;
  font-size: .96rem;
  line-height: 1.78;
  color: var(--c-text-dim);
}

/* ---------- 01 团队构成 ---------- */
.page-about .about-split {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(1.5rem, 4vw, 2.5rem);
}
.page-about .tabs {
  display: block;
}
.page-about .tablist {
  display: flex;
  flex-wrap: wrap;
  gap: .35rem;
  margin-bottom: 1.1rem;
}
.page-about .tab {
  appearance: none;
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  background: transparent;
  color: var(--c-text-dim);
  font-family: var(--font-body);
  font-size: .88rem;
  padding: .48rem .95rem;
  white-space: nowrap;
  cursor: pointer;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}
.page-about .tab:hover {
  color: var(--c-bright);
  border-color: var(--c-ice);
}
.page-about .tab[aria-selected="true"] {
  background: var(--c-glass-strong);
  border-color: var(--c-ice);
  color: var(--c-bright);
}
.page-about .tab:focus-visible {
  outline: 2px solid var(--c-cyan);
  outline-offset: 2px;
}
.page-about .tabpanel {
  border-left: 2px solid var(--c-cyan);
  padding: .15rem 0 .15rem 1rem;
  color: var(--c-text);
  font-size: .96rem;
  line-height: 1.8;
}
.page-about .tabpanel[hidden] {
  display: none;
}
.page-about .tabpanel p {
  margin: 0;
}
.page-about .about-split-side .figure {
  margin: 0;
}
.page-about .about-split-side .figure-frame {
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--c-panel);
}
.page-about .about-split-side .figure-frame img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
}
.page-about .figure-caption {
  margin-top: .65rem;
  font-size: .8rem;
  line-height: 1.65;
  color: var(--c-steel);
}

@media (min-width: 880px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 1.18fr) minmax(0, .82fr);
    align-items: start;
    gap: clamp(1.75rem, 4vw, 3rem);
  }
  .page-about .about-split-side {
    margin-top: 2.25rem;
  }
}

/* ---------- 02 内容链路 ---------- */
.page-about .about-flow-body {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(1.5rem, 4vw, 2.5rem);
}
.page-about .about-flow {
  position: relative;
  margin: 0;
  padding: 0 0 0 .35rem;
  list-style: none;
  display: grid;
  gap: .85rem;
}
.page-about .about-flow-step {
  position: relative;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: .85rem;
  padding: .9rem 1rem .95rem .9rem;
  border: 1px solid var(--c-line-soft);
  border-left: 2px solid var(--c-ice);
  border-radius: var(--radius);
  background: linear-gradient(180deg, var(--c-glass), transparent 68%);
}
.page-about .about-flow-num {
  font-family: var(--font-mono);
  font-size: .88rem;
  line-height: 1.6;
  color: var(--c-cyan);
}
.page-about .about-flow-step h3 {
  margin: 0 0 .3rem;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.06rem;
  letter-spacing: .03em;
  color: var(--c-bright);
}
.page-about .about-flow-step p {
  margin: 0;
  font-size: .93rem;
  line-height: 1.78;
  color: var(--c-text-dim);
}
.page-about .about-flow-figure {
  margin: 0;
}
.page-about .about-flow-figure .figure-frame {
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--c-panel);
}
.page-about .about-flow-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
}

@media (min-width: 900px) {
  .page-about .about-flow-body {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, .85fr);
    align-items: start;
  }
  .page-about .about-flow-step:nth-child(even) {
    margin-left: clamp(1rem, 4vw, 2.75rem);
  }
}

/* ---------- 03 版本保障 ---------- */
.page-about .about-checks {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: .75rem;
}
.page-about .about-check {
  display: grid;
  grid-template-columns: 1fr;
  gap: .35rem;
  padding: 1rem 1.1rem 1.05rem;
  border: 1px solid var(--c-line-soft);
  border-radius: var(--radius);
  background: var(--c-cream);
}
.page-about .about-check-key {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.02rem;
  letter-spacing: .06em;
  color: var(--c-ink);
}
.page-about .about-check-key::before {
  content: "";
  display: inline-block;
  width: 8px;
  height: 8px;
  margin-right: .5rem;
  border-radius: 50%;
  background: var(--c-cyan);
  vertical-align: middle;
}
.page-about .about-check p {
  margin: 0;
  font-size: .93rem;
  line-height: 1.8;
  color: #4a3d34;
}
.page-about .about-inline-link {
  margin: 1.15rem 0 0;
  font-size: .9rem;
  color: var(--c-text-dim);
}
.page-about .about-inline-link a {
  color: var(--c-ice);
  text-decoration: none;
  border-bottom: 1px solid var(--c-line);
  padding-bottom: 1px;
}
.page-about .about-inline-link a:hover {
  border-bottom-color: var(--c-ice);
}

@media (min-width: 760px) {
  .page-about .about-check {
    grid-template-columns: 11rem minmax(0, 1fr);
    gap: 1.25rem;
    align-items: baseline;
  }
}

/* ---------- 04 更新节奏 ---------- */
.page-about .about-metrics {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: .75rem;
  margin: 0 0 1.5rem;
  padding: 0;
  list-style: none;
}
.page-about .about-metric {
  display: flex;
  flex-direction: column;
  gap: .3rem;
  padding: .95rem 1rem 1rem;
  border: 1px solid var(--c-line-soft);
  border-top: 2px solid var(--c-ice);
  border-radius: var(--radius);
  background: var(--c-panel);
}
.page-about .about-metric-value {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(1.7rem, 5vw, 2.35rem);
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--c-bright);
}
.page-about .about-metric-plus {
  font-size: .68em;
  color: var(--c-orange);
  margin-left: .08em;
}
.page-about .about-metric-label {
  font-size: .82rem;
  line-height: 1.6;
  color: var(--c-steel);
}
.page-about .about-rhythm-split {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(1.25rem, 3.5vw, 2.25rem);
}
.page-about .about-rhythm-text p {
  margin: 0 0 .95rem;
  font-size: .95rem;
  line-height: 1.82;
  color: var(--c-text-dim);
}
.page-about .about-rhythm-text p:last-child {
  margin-bottom: 0;
}
.page-about .about-rhythm-figure {
  margin: 0;
}
.page-about .about-rhythm-figure .figure-frame {
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--c-panel);
}
.page-about .about-rhythm-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
}

@media (min-width: 880px) {
  .page-about .about-rhythm-split {
    grid-template-columns: minmax(0, .92fr) minmax(0, 1.08fr);
    align-items: center;
  }
}

/* ---------- 05 合作生态 ---------- */
.page-about .about-folds {
  display: grid;
  gap: .6rem;
}
.page-about .about-fold {
  border: 1px solid var(--c-line-soft);
  border-radius: var(--radius);
  background: var(--c-glass);
  transition: border-color var(--dur) var(--ease);
}
.page-about .about-fold[open] {
  border-color: var(--c-line);
}
.page-about .about-fold summary {
  display: flex;
  align-items: center;
  gap: .6rem;
  padding: .9rem 1.05rem;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: .04em;
  color: var(--c-bright);
}
.page-about .about-fold summary::-webkit-details-marker {
  display: none;
}
.page-about .about-fold summary::before {
  content: "+";
  flex: none;
  width: 1rem;
  font-family: var(--font-mono);
  font-size: 1.05rem;
  line-height: 1;
  color: var(--c-cyan);
  text-align: center;
}
.page-about .about-fold[open] summary::before {
  content: "–";
}
.page-about .about-fold summary:focus-visible {
  outline: 2px solid var(--c-cyan);
  outline-offset: 2px;
}
.page-about .about-fold p {
  margin: 0;
  padding: 0 1.05rem 1rem 2.65rem;
  font-size: .93rem;
  line-height: 1.8;
  color: var(--c-text-dim);
}

/* ---------- 06 找到我们 ---------- */
.page-about .about-contact {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.15rem;
  padding: clamp(1.1rem, 3vw, 1.75rem);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  background:
    linear-gradient(135deg, var(--c-glass), transparent 72%),
    var(--c-panel);
}
.page-about .about-contact-main p {
  margin: 0;
  font-size: .96rem;
  line-height: 1.82;
  color: var(--c-text);
}
.page-about .about-contact-mail {
  font-family: var(--font-mono);
  font-size: .92em;
  color: var(--c-cyan);
  word-break: break-all;
}
.page-about .about-contact-side {
  display: flex;
  align-items: flex-start;
}

@media (min-width: 780px) {
  .page-about .about-contact {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: 2rem;
  }
}

/* ---------- 窄屏收口 ---------- */
@media (max-width: 480px) {
  .page-about .about-hero-actions .btn {
    flex: 1 1 auto;
    text-align: center;
  }
  .page-about .about-metrics {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-metric-value {
    font-size: 1.5rem;
  }
  .page-about .about-section-head {
    gap: .25rem .65rem;
  }
}

/* ---------- 无动画偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition-duration: .01ms !important;
    animation-duration: .01ms !important;
  }
}
<<<END>>>