.page-about {
  --about-rail-w: 248px;
  --about-gap: 40px;
  padding-bottom: calc(var(--dock-h) + 40px);
  background: var(--salt);
}

.page-about .breadcrumb {
  padding: 24px 0 14px;
}

/* ---------- 首屏框景 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius);
  background:
    radial-gradient(120% 140% at 88% 0%, rgba(27,90,120,.85) 0%, rgba(11,53,80,0) 58%),
    linear-gradient(158deg, var(--deep) 0%, var(--ink) 100%);
  color: var(--salt);
  box-shadow: var(--shadow-2);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 120px;
  background: repeating-linear-gradient(
    90deg,
    rgba(102,217,184,.16) 0 1px,
    transparent 1px 22px
  );
  mask-image: linear-gradient(to top, rgba(0,0,0,.9), transparent);
  -webkit-mask-image: linear-gradient(to top, rgba(0,0,0,.9), transparent);
  pointer-events: none;
}

.page-about .about-hero__frame {
  position: relative;
  margin: 14px;
  padding: 30px 20px 26px;
  border: 1px solid rgba(102,217,184,.28);
  border-radius: 8px;
}

.page-about .about-hero__frame::before {
  content: "";
  position: absolute;
  left: 14px;
  right: 14px;
  top: -1px;
  height: 5px;
  background: repeating-linear-gradient(
    90deg,
    rgba(255,107,74,.85) 0 1px,
    transparent 1px 16px
  );
}

.page-about .about-hero__eyebrow {
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--mint);
}

.page-about .about-hero__title {
  margin: 0 0 18px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(30px, 7.6vw, 58px);
  line-height: 1.1;
  letter-spacing: -.01em;
}

.page-about .about-hero__lede {
  margin: 0;
  max-width: 60ch;
  font-size: 16px;
  line-height: 1.8;
  color: rgba(246,248,244,.82);
}

.page-about .about-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 18px 36px;
  margin-top: 28px;
  padding-top: 20px;
  border-top: 1px solid rgba(246,248,244,.16);
}

.page-about .about-stat {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.page-about .about-stat__num {
  font-family: var(--font-mono);
  font-size: 26px;
  line-height: 1;
  color: var(--mint);
  font-variant-numeric: tabular-nums;
}

.page-about .about-stat__label {
  font-size: 12px;
  color: rgba(246,248,244,.66);
}

/* ---------- 主体两栏 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
  padding-top: 40px;
}

.page-about .about-rail {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper);
  box-shadow: var(--shadow-1);
  padding: 18px 16px;
}

.page-about .about-rail__title {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--coral-deep);
}

.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
}

.page-about .about-rail__list a {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 8px 10px;
  border-radius: 8px;
  border-left: 2px solid transparent;
  color: var(--body);
  text-decoration: none;
  font-size: 14px;
  transition: background-color .18s ease, color .18s ease, border-color .18s ease;
}

.page-about .about-rail__list a:hover,
.page-about .about-rail__list a:focus-visible {
  background: var(--mint-mist);
  color: var(--deep);
}

.page-about .about-rail__list a.is-active {
  border-left-color: var(--coral);
  background: var(--salt);
  color: var(--deep);
  font-weight: 500;
}

.page-about .about-rail__num {
  font-size: 11px;
  color: var(--tide-line);
  font-variant-numeric: tabular-nums;
}

.page-about .about-rail__list a.is-active .about-rail__num {
  color: var(--coral-deep);
}

.page-about .about-rail__note {
  margin: 16px 0 0;
  padding-top: 12px;
  border-top: 1px dashed var(--line);
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.7;
  color: var(--body);
}

/* ---------- 章节 ---------- */
.page-about .about-article {
  display: grid;
  gap: 0;
  min-width: 0;
}

.page-about .chapter {
  padding: 0 0 44px;
  margin-bottom: 44px;
  border-bottom: 1px solid var(--line);
}

.page-about .chapter:last-of-type {
  border-bottom: 0;
  margin-bottom: 24px;
}

.page-about .chapter__head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 16px;
}

.page-about .chapter__num {
  font-size: 13px;
  color: var(--coral-deep);
  letter-spacing: .08em;
  padding-top: 6px;
}

.page-about .chapter__title {
  margin: 0;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(22px, 4.4vw, 32px);
  line-height: 1.32;
  color: var(--ink);
}

.page-about .chapter__lede {
  margin: 0 0 16px;
  font-size: 17px;
  line-height: 1.8;
  color: var(--deep);
}

.page-about .chapter p {
  margin: 0 0 14px;
  font-size: 16px;
  line-height: 1.8;
  color: var(--body);
}

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

.page-about .chapter a {
  color: var(--coral-deep);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- 索引地图 ---------- */
.page-about .index-map {
  list-style: none;
  margin: 20px 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .index-map__item {
  border: 1px solid var(--line);
  border-left: 3px solid var(--mint);
  border-radius: var(--radius);
  background: var(--paper);
  box-shadow: var(--shadow-1);
  padding: 16px 16px 18px;
}

.page-about .index-map__k {
  display: inline-block;
  margin-bottom: 8px;
  padding: 2px 8px;
  border-radius: 999px;
  background: var(--mint-mist);
  color: var(--deep);
  font-size: 12px;
  letter-spacing: .12em;
}

.page-about .index-map__h {
  margin: 0 0 8px;
  font-family: var(--font-serif);
  font-size: 18px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .index-map__item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--body);
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  margin: 22px 0 24px;
}

.page-about .about-figure img,
.page-about .contact-band__figure img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.page-about .about-figure .media-frame {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--mint-mist);
  box-shadow: var(--shadow-1);
}

.page-about .media-caption {
  margin-top: 8px;
  font-size: 12px;
  color: var(--body);
}

/* ---------- 时间线 ---------- */
.page-about .timeline {
  list-style: none;
  margin: 26px 0 0;
  padding: 0 0 0 22px;
  border-left: 1px solid var(--line);
}

.page-about .timeline__item {
  position: relative;
  padding: 0 0 26px 18px;
}

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: -27px;
  top: 4px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--paper);
  border: 2px solid var(--coral);
}

.page-about .timeline__item--current::before {
  background: var(--mint);
  border-color: var(--deep);
  box-shadow: 0 0 0 4px rgba(102,217,184,.24);
}

.page-about .timeline__node {
  display: inline-block;
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--coral-deep);
  margin-bottom: 4px;
}

.page-about .timeline__item--current .timeline__node {
  color: var(--tide-line);
}

.page-about .timeline__title {
  margin: 0 0 8px;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 19px;
  line-height: 1.45;
  color: var(--ink);
}

.page-about .timeline__more {
  margin-top: 6px;
  border-top: 1px dashed var(--line);
}

.page-about .timeline__more summary {
  cursor: pointer;
  padding: 8px 0 4px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--tide-line);
  list-style: none;
}

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

.page-about .timeline__more summary::before {
  content: "+ ";
  color: var(--coral-deep);
}

.page-about .timeline__more[open] summary::before {
  content: "– ";
}

.page-about .timeline__more p {
  margin: 0 0 6px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--body);
}

/* ---------- 团队 ---------- */
.page-about .team-grid {
  display: grid;
  gap: 12px;
  margin: 22px 0;
}

.page-about .team-card {
  position: relative;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper);
  box-shadow: var(--shadow-1);
  padding: 18px 16px;
}

.page-about .team-card__num {
  display: block;
  font-size: 22px;
  color: var(--mint);
  line-height: 1;
  margin-bottom: 8px;
}

.page-about .team-card__title {
  margin: 0 0 8px;
  font-family: var(--font-serif);
  font-size: 18px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .team-card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--body);
}

.page-about .rhythm {
  display: grid;
  gap: 1px;
  margin-top: 22px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--line);
}

.page-about .rhythm__item {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 16px;
  background: var(--paper);
}

.page-about .rhythm__num {
  flex: 0 0 auto;
  font-size: 34px;
  line-height: 1;
  color: var(--deep);
  font-variant-numeric: tabular-nums;
}

.page-about .rhythm__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--body);
}

/* ---------- 双端互补 ---------- */
.page-about .chapter--tide {
  background: linear-gradient(180deg, var(--mint-mist) 0%, rgba(216,245,234,0) 100%);
  border-radius: var(--radius);
  padding: 24px 16px 28px;
  margin-left: -16px;
  margin-right: -16px;
}

.page-about .dual {
  display: grid;
  gap: 14px;
  margin-top: 8px;
}

.page-about .dual__panel {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper);
  padding: 18px 16px;
  box-shadow: var(--shadow-1);
}

.page-about .dual__panel--dark {
  background: var(--deep);
  border-color: var(--deep);
  color: var(--salt);
}

.page-about .dual__label {
  margin: 0 0 10px;
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--tide-line);
}

.page-about .dual__panel--dark .dual__label {
  color: var(--mint);
}

.page-about .dual__title {
  margin: 0 0 10px;
  font-family: var(--font-serif);
  font-size: 19px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--ink);
}

.page-about .dual__panel--dark .dual__title {
  color: var(--salt);
}

.page-about .dual__panel p {
  margin: 0 0 10px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--body);
}

.page-about .dual__panel--dark p {
  color: rgba(246,248,244,.82);
}

.page-about .dual__foot {
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px dashed var(--line);
  font-size: 15px;
  line-height: 1.75;
  color: var(--deep);
}

/* ---------- 规模条 ---------- */
.page-about .scale-strip {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 22px 0 18px;
  border: 1px solid var(--deep);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--deep);
}

.page-about .scale-strip__cell {
  background: var(--deep);
  padding: 14px 12px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.page-about .scale-strip__num {
  font-size: 20px;
  line-height: 1;
  color: var(--mint);
  font-variant-numeric: tabular-nums;
}

.page-about .scale-strip__label {
  font-size: 12px;
  line-height: 1.5;
  color: rgba(246,248,244,.72);
}

/* ---------- 联系 ---------- */
.page-about .contact-band {
  display: grid;
  gap: 18px;
  margin-top: 10px;
  padding: 18px 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper);
  box-shadow: var(--shadow-1);
}

.page-about .contact-band .contact-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px 12px;
  padding: 10px 0;
  border-bottom: 1px dashed var(--line);
}

.page-about .contact-band .contact-row__label {
  flex: 0 0 72px;
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--tide-line);
}

.page-about .contact-band .contact-row__value {
  flex: 1 1 160px;
  min-width: 0;
  font-size: 15px;
  word-break: break-word;
  color: var(--deep);
}

.page-about .contact-band .copy-btn {
  flex: 0 0 auto;
  padding: 5px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--salt);
  color: var(--deep);
  font-size: 12px;
  cursor: pointer;
  transition: border-color .18s ease, color .18s ease;
}

.page-about .contact-band .copy-btn:hover,
.page-about .contact-band .copy-btn:focus-visible {
  border-color: var(--coral);
  color: var(--coral-deep);
}

.page-about .contact-band .copy-btn[data-copied] {
  border-color: var(--mint);
  color: var(--tide-line);
  background: var(--mint-mist);
}

.page-about .contact-band__note {
  margin: 14px 0 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--body);
}

.page-about .contact-band__figure {
  margin: 0;
}

.page-about .contact-band__figure .media-frame {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--mint-mist);
}

.page-about .contact-band__tip {
  margin-top: 14px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--body);
}

/* ---------- 继续了解 ---------- */
.page-about .about-next {
  border-top: 2px solid var(--deep);
  padding-top: 22px;
}

.page-about .about-next__title {
  margin: 0 0 14px;
  font-family: var(--font-serif);
  font-size: 22px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .about-next__links {
  display: grid;
  gap: 8px;
}

.page-about .about-next__link {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 14px 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper);
  text-decoration: none;
  color: var(--deep);
  font-size: 15px;
  line-height: 1.65;
  transition: border-color .18s ease, transform .18s ease;
}

.page-about .about-next__link:hover,
.page-about .about-next__link:focus-visible {
  border-color: var(--coral);
  transform: translateX(2px);
}

.page-about .about-next__num {
  flex: 0 0 auto;
  color: var(--coral-deep);
  font-size: 14px;
}

/* ---------- 媒体查询 ---------- */
@media (min-width: 640px) {
  .page-about .about-hero__frame {
    margin: 18px;
    padding: 40px 32px 32px;
  }

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

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

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

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

  .page-about .scale-strip {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }

  .page-about .contact-band {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
    align-items: start;
    padding: 22px 20px;
  }

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

@media (min-width: 960px) {
  .page-about {
    --about-gap: 52px;
  }

  .page-about .breadcrumb {
    padding: 32px 0 18px;
  }

  .page-about .about-hero__frame {
    margin: 22px;
    padding: 52px 44px 40px;
  }

  .page-about .about-hero__lede {
    font-size: 17px;
  }

  .page-about .about-body {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: var(--about-gap);
    align-items: start;
    padding-top: 54px;
  }

  .page-about .about-rail {
    position: sticky;
    top: 96px;
    padding: 20px 16px;
  }

  .page-about .chapter--tide {
    margin-left: 0;
    margin-right: 0;
    padding: 28px 28px 32px;
  }

  .page-about .chapter__head {
    gap: 18px;
  }

  .page-about .chapter__num {
    font-size: 14px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__list a,
  .page-about .contact-band .copy-btn,
  .page-about .about-next__link {
    transition: none;
  }

  .page-about .about-next__link:hover,
  .page-about .about-next__link:focus-visible {
    transform: none;
  }
}
<<<PAGE_CSS_END>>>
<<<END>>>
```