.page-about {
  background-color: var(--turf-deep);
  color: var(--cold);
  padding-bottom: 4rem;
}

.page-about .breadcrumb {
  padding-top: 1.75rem;
  margin-bottom: 1.25rem;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-bottom: 2.5rem;
  border-bottom: 1px solid rgba(198, 255, 74, 0.16);
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
}

.page-about .about-hero__copy .micro-index {
  color: var(--gray);
  margin-bottom: 1.25rem;
}

.page-about .about-hero__title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(2.1rem, 8.2vw, 4.6rem);
  line-height: 1.02;
  letter-spacing: -0.02em;
  color: var(--cold);
  margin-bottom: 1.5rem;
  max-width: 18ch;
}

.page-about .about-hero__lede {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.85;
  color: rgba(244, 247, 242, 0.82);
  max-width: 46ch;
}

.page-about .about-hero__media {
  align-self: end;
}

/* ---------- 长卷布局 ---------- */
.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 2.5rem;
  padding-top: 2.5rem;
}

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

/* ---------- 章节 ---------- */
.page-about .chapter {
  padding-block: 2rem 2.5rem;
  border-bottom: 1px solid rgba(154, 167, 158, 0.18);
  scroll-margin-top: 7rem;
}

.page-about .chapter__head {
  display: flex;
  align-items: baseline;
  gap: 0.85rem;
  margin-bottom: 1.35rem;
}

.page-about .chapter__num {
  font-family: var(--font-display);
  font-weight: 200;
  font-size: clamp(2.1rem, 9vw, 4.4rem);
  line-height: 0.8;
  letter-spacing: -0.04em;
  color: var(--gray);
  opacity: 0.45;
  flex: none;
}

.page-about .chapter__title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.35rem, 4.6vw, 2.1rem);
  line-height: 1.15;
  letter-spacing: -0.01em;
  color: var(--cold);
  margin: 0;
}

.page-about .chapter__body {
  max-width: 42rem;
}

.page-about .chapter__body p {
  font-size: 1rem;
  line-height: 1.85;
  color: rgba(244, 247, 242, 0.84);
}

.page-about .chapter__body p + p {
  margin-top: 1.05rem;
}

.page-about .chapter__body a {
  color: var(--lime);
  text-decoration: none;
  border-bottom: 1px solid rgba(198, 255, 74, 0.45);
  padding-bottom: 1px;
  transition: border-color 0.2s ease, color 0.2s ease;
}

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

/* ---------- 数据条 ---------- */
.page-about .about-figures {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 1.75rem 0;
  background-color: rgba(154, 167, 158, 0.22);
  border: 1px solid rgba(154, 167, 158, 0.22);
}

.page-about .about-figure {
  background-color: var(--turf-mid);
  padding: 1.1rem 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.page-about .about-figure__value {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(1.4rem, 5.2vw, 1.85rem);
  line-height: 1.1;
  color: var(--lime);
  letter-spacing: -0.01em;
}

.page-about .about-figure__label {
  font-family: var(--font-body);
  font-size: 0.8rem;
  letter-spacing: 0.06em;
  color: var(--gray);
}

/* ---------- 时间线 ---------- */
.page-about .timeline {
  position: relative;
  margin-top: 1.75rem;
  list-style: none;
  padding: 0;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 5.5rem;
  top: 0.55rem;
  bottom: 1.6rem;
  width: 1px;
  background: linear-gradient(to bottom, rgba(198, 255, 74, 0.45), rgba(198, 255, 74, 0.06));
}

.page-about .timeline__item {
  position: relative;
  display: grid;
  grid-template-columns: 5.5rem minmax(0, 1fr);
  gap: 1.5rem;
  padding-bottom: 1.65rem;
  scroll-margin-top: 7rem;
}

.page-about .timeline__item:last-child {
  padding-bottom: 0;
}

.page-about .timeline__year {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--lime);
  text-align: right;
  padding-right: 1.25rem;
  padding-top: 0.1rem;
  line-height: 1.4;
}

.page-about .timeline__item::after {
  content: "";
  position: absolute;
  left: 5.5rem;
  top: 0.42rem;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background-color: var(--lime);
  box-shadow: 0 0 0 3px rgba(198, 255, 74, 0.14);
  transform: translateX(-50%);
}

.page-about .timeline__text p {
  font-size: 0.95rem;
  line-height: 1.75;
  color: rgba(244, 247, 242, 0.82);
  max-width: 34rem;
}

/* ---------- 图片 ---------- */
.page-about .about-media {
  margin-top: 1.9rem;
}

.page-about .media-frame img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 收束 ---------- */
.page-about .about-close {
  padding-top: 2.25rem;
}

.page-about .about-close__note {
  font-size: 0.95rem;
  line-height: 1.8;
  color: var(--gray);
  max-width: 40rem;
}

.page-about .about-close__note a {
  color: var(--cold);
  text-decoration: none;
  border-bottom: 1px solid rgba(198, 255, 74, 0.5);
  transition: color 0.2s ease, border-color 0.2s ease;
}

.page-about .about-close__note a:hover,
.page-about .about-close__note a:focus-visible {
  color: var(--lime);
  border-bottom-color: var(--lime);
}

/* ---------- 年份索引 ---------- */
.page-about .about-rail {
  display: none;
}

.page-about .about-rail__inner {
  background-color: var(--turf-mid);
  border: 1px solid rgba(198, 255, 74, 0.2);
  padding: 1.25rem 1.1rem;
}

.page-about .about-rail__inner .micro-index {
  color: var(--gray);
  margin-bottom: 0.9rem;
}

.page-about .rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0.1rem;
}

.page-about .rail__link {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  letter-spacing: 0.08em;
  color: rgba(244, 247, 242, 0.62);
  text-decoration: none;
  padding: 0.4rem 0.5rem;
  border-left: 2px solid transparent;
  transition: color 0.18s ease, border-color 0.18s ease, background-color 0.18s ease;
}

.page-about .rail__link:hover,
.page-about .rail__link:focus-visible {
  color: var(--lime);
  border-left-color: var(--lime);
  background-color: rgba(198, 255, 74, 0.07);
}

.page-about .rail__link:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-figures {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-hero {
    padding-bottom: 3rem;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 5.5fr) minmax(0, 6.5fr);
    align-items: end;
    gap: 3rem;
  }

  .page-about .chapter {
    padding-block: 2.75rem 3.25rem;
  }

  .page-about .chapter__head {
    gap: 1.25rem;
    margin-bottom: 1.6rem;
  }
}

@media (min-width: 1060px) {
  .page-about .about-layout {
    grid-template-columns: minmax(0, 7.6fr) minmax(0, 2.4fr);
    gap: 4.5rem;
    align-items: start;
  }

  .page-about .about-rail {
    display: block;
    position: sticky;
    top: 6.5rem;
  }
}

@media (max-width: 559px) {
  .page-about .timeline::before {
    left: 0.3rem;
    top: 0.55rem;
  }

  .page-about .timeline__item {
    grid-template-columns: minmax(0, 1fr);
    gap: 0.3rem;
    padding-left: 1.6rem;
  }

  .page-about .timeline__year {
    text-align: left;
    padding-right: 0;
  }

  .page-about .timeline__item::after {
    left: 0.3rem;
    top: 0.32rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .rail__link,
  .page-about .chapter__body a,
  .page-about .about-close__note a {
    transition: none;
  }
}
<<<END>>>