.page-about {
  --about-rail-w: 190px;
  --about-ink-soft: rgba(244, 241, 234, .8);
  --about-ink-faint: rgba(244, 241, 234, .62);
  background: var(--steel-deep);
  color: var(--paper-warm);
  font-family: var(--font-sans);
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: clamp(28px, 5vw, 56px) 0 clamp(44px, 7vw, 96px);
  border-bottom: 1px solid var(--line);
}

.page-about .crumbs {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--muted-steel);
}
.page-about .crumbs a {
  color: var(--muted-steel);
  text-decoration: none;
}
.page-about .crumbs a:hover {
  color: var(--cyan-signal);
}
.page-about .crumbs__sep {
  margin: 0 8px;
  color: var(--line-strong);
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gap);
  align-items: end;
  margin-top: clamp(36px, 6vw, 76px);
}
.page-about .about-hero__lead {
  grid-column: 1 / 7;
}
.page-about .about-hero__aside {
  grid-column: 8 / 13;
  padding-bottom: 6px;
}

.page-about .about-hero .eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--cyan-signal);
}

.page-about .about-hero .display {
  margin: clamp(14px, 2vw, 22px) 0 0;
  font-size: clamp(2.1rem, 5.6vw, 4rem);
  font-weight: 900;
  line-height: 1.04;
  letter-spacing: -0.02em;
  color: var(--paper-warm);
}

.page-about .about-hero .lede {
  margin: clamp(18px, 3vw, 28px) 0 0;
  max-width: 46ch;
  font-family: var(--font-serif);
  font-size: clamp(16px, 1.4vw, 19px);
  line-height: 1.72;
  color: var(--about-ink-soft);
}

.page-about .about-scale {
  display: block;
  width: 100%;
  max-width: 360px;
  height: auto;
  margin-left: auto;
}
.page-about .about-scale__base {
  stroke: var(--line-strong);
  stroke-width: 1;
}
.page-about .about-scale__tick line {
  stroke-width: 2;
}
.page-about .about-scale__tick .t1 { stroke: var(--cyan-signal); }
.page-about .about-scale__tick .t2 { stroke: var(--electric-blue); }
.page-about .about-scale__tick .t3 { stroke: var(--sand-soft); }
.page-about .about-scale__tick .t4 { stroke: var(--violet-signal); }

.page-about .about-scale__cap {
  margin: 14px 0 0;
  font-size: 11px;
  letter-spacing: .1em;
  text-align: right;
  color: var(--muted-steel);
}

/* ---------- 主体骨架：左侧编号栏 + 右侧流 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
  gap: clamp(28px, 5vw, 72px);
  padding-top: clamp(48px, 8vw, 100px);
  padding-bottom: clamp(72px, 11vw, 150px);
}

.page-about .about-rail {
  position: sticky;
  top: 96px;
  align-self: start;
}
.page-about .about-rail__label {
  margin: 0 0 14px;
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--muted-steel);
}
.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.page-about .about-rail .toc__link {
  display: block;
  padding: 7px 0 7px 12px;
  border-left: 1px solid var(--line);
  font-size: 14px;
  line-height: 1.35;
  color: var(--about-ink-faint);
  text-decoration: none;
  transition: color 160ms var(--ease), border-color 160ms var(--ease);
}
.page-about .about-rail .toc__link .mono {
  display: block;
  margin-bottom: 2px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .12em;
  color: var(--muted-steel);
}
.page-about .about-rail .toc__link:hover,
.page-about .about-rail .toc__link.is-active,
.page-about .about-rail .toc__link[aria-current="true"] {
  color: var(--paper-warm);
  border-left-color: var(--cyan-signal);
}
.page-about .about-rail .toc__link:focus-visible {
  outline: 2px solid var(--electric-blue);
  outline-offset: 3px;
}

.page-about .about-flow {
  display: flex;
  flex-direction: column;
  gap: clamp(56px, 9vw, 124px);
  min-width: 0;
}

/* ---------- 章节节点：宽度交替 ---------- */
.page-about .about-node {
  max-width: 74ch;
  min-width: 0;
}
.page-about .about-node--wide {
  max-width: 100%;
}
.page-about .about-node--narrow {
  max-width: 60ch;
}

.page-about .about-node--paper {
  max-width: 66ch;
  padding: clamp(24px, 4vw, 46px);
  border-radius: var(--radius);
  background: var(--paper-warm);
  color: var(--ink-text);
}

.page-about .sec-head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  gap: 8px 18px;
  align-items: baseline;
  margin-bottom: clamp(20px, 3vw, 34px);
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line);
}
.page-about .sec-head__idx {
  grid-column: 1;
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--cyan-signal);
}
.page-about .sec-head__title {
  grid-column: 2;
  margin: 0;
  font-size: clamp(1.4rem, 2.7vw, 2.1rem);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.01em;
  color: var(--paper-warm);
}
.page-about .sec-head__note {
  grid-column: 3;
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .08em;
  text-align: right;
  white-space: nowrap;
  color: var(--muted-steel);
}

.page-about .about-node--paper .sec-head {
  border-bottom-color: var(--line-dark);
}
.page-about .about-node--paper .sec-head__idx { color: var(--cyan-dim); }
.page-about .about-node--paper .sec-head__title { color: var(--ink-text); }
.page-about .about-node--paper .sec-head__note { color: var(--muted-steel); }

/* ---------- 正文 ---------- */
.page-about .prose {
  font-size: 16.5px;
  line-height: 1.78;
  color: var(--about-ink-soft);
}
.page-about .prose p {
  margin: 0 0 1.05em;
  max-width: 68ch;
}
.page-about .prose p:last-child {
  margin-bottom: 0;
}
.page-about .about-node--paper .prose {
  color: rgba(16, 24, 32, .84);
}

/* ---------- 数据铭牌 ---------- */
.page-about .about-plates {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: var(--gap);
  margin: 0 0 clamp(24px, 4vw, 40px);
}
.page-about .plate {
  padding: 20px 18px;
  border: 1px solid var(--line);
  border-left: 3px solid var(--cyan-signal);
  border-radius: var(--radius);
  background: var(--steel-mid);
}
.page-about .plate__val {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(1.8rem, 3.4vw, 2.5rem);
  font-weight: 700;
  line-height: 1.1;
  color: var(--paper-warm);
}
.page-about .plate__val span {
  margin-left: .3em;
  font-size: .4em;
  color: var(--sand-orange);
}
.page-about .plate__label {
  margin: 8px 0 0;
  font-size: 13px;
  line-height: 1.5;
  color: var(--muted-steel);
}

/* ---------- 专利族维护组列表 ---------- */
.page-about .about-fams {
  list-style: none;
  margin: clamp(24px, 4vw, 40px) 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
}
.page-about .about-fam {
  position: relative;
  display: grid;
  grid-template-columns: 84px minmax(0, 1fr) auto;
  gap: 6px 22px;
  align-items: start;
  padding: clamp(18px, 3vw, 28px) 0 clamp(18px, 3vw, 28px) 20px;
  border-bottom: 1px solid var(--line);
}
.page-about .about-fam__bar {
  position: absolute;
  left: 0;
  top: clamp(18px, 3vw, 28px);
  bottom: clamp(18px, 3vw, 28px);
  width: 3px;
  border-radius: 2px;
  transition: width 180ms var(--ease);
}
.page-about .about-fam:hover .about-fam__bar {
  width: 5px;
}
.page-about .about-fam--pf01 .about-fam__bar { background: var(--cyan-signal); }
.page-about .about-fam--pf02 .about-fam__bar { background: var(--electric-blue); }
.page-about .about-fam--pf03 .about-fam__bar { background: var(--sand-soft); }
.page-about .about-fam--pf04 .about-fam__bar { background: var(--violet-signal); }

.page-about .about-fam__code {
  grid-column: 1;
  margin: 2px 0 0;
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: .1em;
  color: var(--cyan-signal);
}
.page-about .about-fam--pf02 .about-fam__code { color: var(--electric-blue); }
.page-about .about-fam--pf03 .about-fam__code { color: var(--sand-soft); }
.page-about .about-fam--pf04 .about-fam__code { color: var(--violet-signal); }

.page-about .about-fam__text {
  grid-column: 2;
  min-width: 0;
}
.page-about .about-fam__title {
  margin: 0 0 8px;
  font-size: clamp(1.05rem, 1.8vw, 1.2rem);
  font-weight: 700;
  line-height: 1.4;
  color: var(--paper-warm);
}
.page-about .about-fam__text p {
  margin: 0;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.75;
  color: var(--about-ink-soft);
}
.page-about .about-fam__tag {
  grid-column: 3;
  margin: 3px 0 0;
  font-size: 11.5px;
  letter-spacing: .08em;
  white-space: nowrap;
  color: var(--muted-steel);
}

/* ---------- 图片 ---------- */
.page-about .media {
  margin: clamp(28px, 4vw, 44px) 0 0;
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--steel-mid);
  border: 1px solid var(--line);
}
.page-about .media img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
}
.page-about .media--slant img {
  clip-path: polygon(0 0, 100% 0, 100% 94%, 0 100%);
}
.page-about .media__cap {
  padding: 10px 14px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .06em;
  color: var(--muted-steel);
  border-top: 1px solid var(--line);
}
.page-about .about-node__figure {
  max-width: 760px;
}

/* ---------- 图文并置 ---------- */
.page-about .about-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: clamp(24px, 4vw, 48px);
  align-items: start;
}
.page-about .about-split__media {
  margin-top: 0;
}
.page-about .about-split__text .prose p {
  max-width: 60ch;
}
.page-about .about-split--flip .about-split__media {
  order: 2;
}

/* ---------- 区域码条 ---------- */
.page-about .about-zones {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 12px;
  margin: clamp(24px, 4vw, 36px) 0 0;
  padding: 0;
}
.page-about .about-zone {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--steel-mid);
}
.page-about .about-zone__code {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .1em;
  color: var(--paper-warm);
}
.page-about .about-zone__name {
  font-size: 13px;
  color: var(--muted-steel);
}

/* ---------- 提示条 ---------- */
.page-about .callout {
  margin: clamp(26px, 4vw, 40px) 0 0;
  padding: clamp(18px, 3vw, 26px);
  border: 1px solid var(--line);
  border-left: 3px solid var(--sand-orange);
  border-radius: var(--radius);
  background: var(--steel-mid);
}
.page-about .callout__idx {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .12em;
  color: var(--sand-orange);
}
.page-about .callout p {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--about-ink-soft);
}
.page-about .callout a {
  color: var(--cyan-signal);
  text-decoration: none;
  border-bottom: 1px solid var(--cyan-dim);
}
.page-about .callout a:hover {
  color: var(--paper-warm);
  border-bottom-color: var(--sand-orange);
}

/* ---------- 响应式 ---------- */
@media (max-width: 1024px) {
  .page-about .about-body {
    grid-template-columns: 160px minmax(0, 1fr);
    gap: 32px;
  }
  .page-about .about-fam {
    grid-template-columns: 76px minmax(0, 1fr);
  }
  .page-about .about-fam__tag {
    grid-column: 2;
  }
}

@media (max-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1fr);
    margin-top: 28px;
  }
  .page-about .about-hero__lead,
  .page-about .about-hero__aside {
    grid-column: 1 / -1;
  }
  .page-about .about-hero__aside {
    margin-top: 26px;
  }
  .page-about .about-scale {
    margin-left: 0;
  }
  .page-about .about-scale__cap {
    text-align: left;
  }
  .page-about .about-body {
    grid-template-columns: minmax(0, 1fr);
    gap: 0;
    padding-top: clamp(32px, 6vw, 56px);
  }
  .page-about .about-rail {
    position: static;
    margin-bottom: 44px;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--line);
  }
  .page-about .about-rail__list {
    flex-direction: row;
    flex-wrap: wrap;
    gap: 6px 0;
  }
  .page-about .about-rail .toc__link {
    padding: 6px 14px 6px 0;
    border-left: 0;
    border-bottom: 1px solid var(--line);
  }
  .page-about .about-rail .toc__link .mono {
    display: inline;
    margin: 0 6px 0 0;
  }
  .page-about .about-rail .toc__link:hover,
  .page-about .about-rail .toc__link.is-active,
  .page-about .about-rail .toc__link[aria-current="true"] {
    border-left-color: transparent;
    border-bottom-color: var(--cyan-signal);
  }
  .page-about .about-flow {
    gap: clamp(48px, 9vw, 84px);
  }
  .page-about .about-node,
  .page-about .about-node--narrow,
  .page-about .about-node--paper {
    max-width: 100%;
  }
  .page-about .about-split {
    grid-template-columns: minmax(0, 1fr);
  }
  .page-about .about-split--flip .about-split__media {
    order: 0;
  }
}

@media (max-width: 640px) {
  .page-about .sec-head {
    grid-template-columns: auto minmax(0, 1fr);
    gap: 6px 14px;
  }
  .page-about .sec-head__title {
    grid-column: 2;
  }
  .page-about .sec-head__note {
    grid-column: 2;
    text-align: left;
    white-space: normal;
  }
  .page-about .about-fam {
    grid-template-columns: minmax(0, 1fr);
    gap: 8px;
    padding-left: 16px;
  }
  .page-about .about-fam__code,
  .page-about .about-fam__text,
  .page-about .about-fam__tag {
    grid-column: 1;
  }
  .page-about .about-plates {
    grid-template-columns: minmax(0, 1fr);
  }
  .page-about .about-node__figure {
    max-width: 100%;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-fam__bar,
  .page-about .about-rail .toc__link {
    transition: none;
  }
  .page-about .about-fam:hover .about-fam__bar {
    width: 3px;
  }
}
<<<END>>>