.page-about {
  --about-card: rgba(16, 42, 68, 0.72);
  --about-rail: 300px;
  background: var(--night-900);
  color: var(--fog);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: 22px 0 48px;
  background: var(--night-900);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -60px;
  right: -34%;
  width: 92%;
  height: 300px;
  background: var(--pitch-700);
  clip-path: polygon(30% 0, 100% 0, 100% 100%, 0 100%);
  opacity: 0.92;
  z-index: 0;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 120px;
  height: 4px;
  background: var(--whistle);
  z-index: 2;
}

.page-about .about-hero .wrap {
  position: relative;
  z-index: 1;
}

.page-about .breadcrumb ol {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 0 0 20px;
  padding: 0;
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  color: var(--text-mute);
}

.page-about .breadcrumb li + li::before {
  content: "/";
  margin-right: 6px;
  color: var(--pitch-500);
}

.page-about .breadcrumb a {
  color: var(--text-soft);
  text-decoration: none;
}

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

.page-about .eyebrow {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--board);
  margin: 0 0 10px;
}

.page-about .about-hero__title {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(1.85rem, 6.2vw, 3.5rem);
  line-height: 1.14;
  letter-spacing: 0.01em;
  margin: 0 0 18px;
  color: var(--fog);
  max-width: 16ch;
}

.page-about .about-hero__title em {
  font-style: normal;
  color: var(--board);
}

.page-about .about-hero__lead {
  max-width: 48ch;
  margin: 0;
  font-size: 1rem;
  line-height: 1.85;
  color: var(--text-soft);
}

/* ---------- 数据看板 ---------- */
.page-about .board {
  margin-top: 34px;
  padding: 16px;
  background: rgba(7, 21, 35, 0.6);
  border: 1px solid var(--line-strong);
}

.page-about .board-filters {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 16px;
}

.page-about .board-btn {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.08em;
  padding: 8px 14px;
  background: transparent;
  border: 1px solid var(--line-strong);
  color: var(--text-soft);
  cursor: pointer;
  transition: background 0.2s var(--ease), color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .board-btn:hover,
.page-about .board-btn:focus-visible {
  border-color: var(--board);
  color: var(--board);
}

.page-about .board-btn[aria-pressed="true"] {
  background: var(--whistle);
  border-color: var(--whistle);
  color: var(--night-900);
  font-weight: 700;
}

.page-about .board-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(142px, 1fr));
  gap: 10px;
}

.page-about .board-tile {
  padding: 14px 12px;
  background: rgba(42, 156, 120, 0.14);
  border-left: 3px solid var(--pitch-500);
}

.page-about .board-tile__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.5rem;
  line-height: 1.15;
  color: var(--board);
  letter-spacing: 0.01em;
}

.page-about .board-tile__label {
  display: block;
  margin-top: 5px;
  font-size: 0.78rem;
  line-height: 1.55;
  color: var(--text-soft);
}

/* ---------- 主体骨架 ---------- */
.page-about .about-body {
  padding-top: 40px;
  padding-bottom: 48px;
}

.page-about .about-grid {
  display: grid;
  gap: 32px;
}

/* ---------- 粘性索引 ---------- */
.page-about .about-rail {
  padding: 18px 0 0;
  border-top: 2px solid var(--pitch-700);
}

.page-about .rail-title {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  color: var(--board);
  margin: 0 0 12px;
}

.page-about .rail-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0 8px;
  counter-reset: rail;
}

.page-about .rail-list li {
  counter-increment: rail;
  flex: 0 0 auto;
}

.page-about .rail-list a {
  display: block;
  padding: 8px 10px 8px 0;
  font-size: 0.9rem;
  color: var(--text-soft);
  text-decoration: none;
  border-bottom: 1px solid var(--line);
  transition: color 0.2s var(--ease);
}

.page-about .rail-list a::before {
  content: counter(rail, decimal-leading-zero);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--whistle);
  margin-right: 8px;
}

.page-about .rail-list a:hover,
.page-about .rail-list a:focus-visible {
  color: var(--board);
}

.page-about .rail-note {
  margin: 22px 0 0;
  padding: 16px 18px;
  font-family: var(--font-serif);
  font-size: 1rem;
  line-height: 1.7;
  color: var(--fog);
  background: var(--pitch-700);
  clip-path: polygon(0 0, 100% 0, 100% 84%, 0 100%);
}

/* ---------- 章节叙事 ---------- */
.page-about .chapter {
  padding: 36px 0;
  border-top: 1px solid var(--line);
}

.page-about .chapter:first-of-type {
  border-top: 0;
  padding-top: 0;
}

.page-about .chapter__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.2em;
  color: var(--whistle);
  margin-bottom: 8px;
}

.page-about .chapter h2 {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(1.35rem, 3.6vw, 2rem);
  line-height: 1.28;
  margin: 0 0 16px;
  color: var(--fog);
}

.page-about .chapter p {
  margin: 0 0 14px;
  font-size: 0.96rem;
  line-height: 1.9;
  color: var(--text-soft);
}

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

.page-about .media-frame {
  margin: 22px 0;
}

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

/* ---------- 九城示意 ---------- */
.page-about .city-map {
  margin: 22px 0;
  padding: 14px;
  background: var(--about-card);
  border: 1px solid var(--line);
}

.page-about .city-map svg {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .city-map__cells rect {
  fill: var(--pitch-700);
  stroke: var(--night-900);
  stroke-width: 2;
}

.page-about .city-map__cells rect.is-home {
  fill: var(--whistle);
}

.page-about .city-map__labels text {
  fill: var(--fog);
  font-family: var(--font-body);
  font-size: 16px;
  font-weight: 600;
  text-anchor: middle;
}

.page-about .city-map figcaption {
  margin-top: 10px;
  font-size: 0.78rem;
  line-height: 1.6;
  color: var(--text-mute);
}

.page-about .axis-list {
  list-style: none;
  margin: 20px 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .axis-list li {
  padding: 14px 16px;
  font-size: 0.9rem;
  line-height: 1.7;
  color: var(--text-soft);
  background: rgba(16, 42, 68, 0.6);
  border-left: 2px solid var(--pitch-500);
}

.page-about .axis-list__tag {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.12em;
  color: var(--board);
  margin-bottom: 4px;
}

/* ---------- 节奏带 ---------- */
.page-about .pace-strip {
  display: grid;
  gap: 10px;
  margin: 22px 0 0;
}

.page-about .pace-strip__item {
  padding: 14px 16px;
  background: var(--about-card);
  border-top: 2px solid var(--whistle);
}

.page-about .pace-strip__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.15rem;
  color: var(--board);
  margin-bottom: 4px;
}

.page-about .pace-strip__text {
  display: block;
  font-size: 0.84rem;
  line-height: 1.6;
  color: var(--text-soft);
}

/* ---------- 时间线 ---------- */
.page-about .seasons {
  list-style: none;
  margin: 10px 0 0;
  padding: 0;
  position: relative;
}

.page-about .seasons::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 8px;
  bottom: 12px;
  width: 2px;
  background: var(--line-strong);
}

.page-about .season {
  position: relative;
  padding: 0 0 26px 30px;
}

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

.page-about .season::before {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  width: 14px;
  height: 14px;
  background: var(--whistle);
  transform: rotate(45deg);
}

.page-about .season__year {
  display: block;
  font-family: var(--font-mono);
  font-size: 1rem;
  letter-spacing: 0.08em;
  color: var(--board);
}

.page-about .season h3 {
  margin: 4px 0 6px;
  font-size: 1rem;
  font-weight: 700;
  color: var(--fog);
}

.page-about .season p {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.8;
  color: var(--text-soft);
}

/* ---------- 展开 ---------- */
.page-about .about-toggle {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin: 4px 0 0;
  padding: 10px 18px;
  font: inherit;
  font-size: 0.88rem;
  background: transparent;
  border: 1px solid var(--line-strong);
  color: var(--fog);
  cursor: pointer;
  transition: border-color 0.2s var(--ease), color 0.2s var(--ease);
}

.page-about .about-toggle::after {
  content: "＋";
  font-family: var(--font-mono);
  color: var(--whistle);
}

.page-about .about-toggle[aria-expanded="true"]::after {
  content: "－";
}

.page-about .about-toggle:hover,
.page-about .about-toggle:focus-visible {
  border-color: var(--whistle);
  color: var(--board);
}

.page-about .venue-kinds {
  display: grid;
  gap: 12px;
  margin-top: 16px;
}

.page-about .venue-kind {
  padding: 14px 16px;
  background: var(--about-card);
  border-top: 2px solid var(--pitch-500);
}

.page-about .venue-kind h4 {
  margin: 0 0 6px;
  font-size: 0.94rem;
  color: var(--fog);
}

.page-about .venue-kind p {
  margin: 0;
  font-size: 0.85rem;
  line-height: 1.7;
  color: var(--text-soft);
}

/* ---------- 斜切引语 ---------- */
.page-about .quote-slab {
  margin: 34px 0;
  padding: 34px 26px;
  background: var(--pitch-700);
  clip-path: polygon(0 0, 100% 6%, 100% 100%, 0 94%);
}

.page-about .quote-slab p {
  margin: 0;
  font-family: var(--font-serif);
  font-size: clamp(1.1rem, 3vw, 1.55rem);
  line-height: 1.7;
  color: var(--fog);
}

/* ---------- 行动 ---------- */
.page-about .story-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 20px;
}

/* ---------- 收尾 ---------- */
.page-about .closing {
  display: grid;
  gap: 0;
  background: var(--night-700);
  border-top: 4px solid var(--pitch-500);
}

.page-about .closing__media img {
  display: block;
  width: 100%;
  height: 100%;
  min-height: 200px;
  object-fit: cover;
}

.page-about .closing__text {
  padding: 30px 22px 36px;
}

.page-about .closing__text h2 {
  font-family: var(--font-serif);
  font-size: clamp(1.3rem, 3.8vw, 1.9rem);
  line-height: 1.3;
  margin: 0 0 12px;
  color: var(--fog);
}

.page-about .closing__text p {
  margin: 0;
  font-size: 0.94rem;
  line-height: 1.85;
  color: var(--text-soft);
  max-width: 42ch;
}

.page-about .closing__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 20px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-hero {
    padding: 28px 0 60px;
  }

  .page-about .board {
    padding: 20px;
  }

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

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

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

  .page-about .quote-slab {
    padding: 42px 36px;
  }
}

@media (min-width: 1024px) {
  .page-about .about-hero::before {
    width: 62%;
    height: 360px;
    right: -12%;
  }

  .page-about .about-hero__title {
    max-width: 22ch;
  }

  .page-about .about-hero__lead {
    font-size: 1.05rem;
  }

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

  .page-about .about-grid {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: 56px;
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: 88px;
    padding-top: 22px;
  }

  .page-about .rail-list {
    display: block;
    gap: 0;
  }

  .page-about .rail-list a {
    padding: 9px 0;
    font-size: 0.92rem;
  }

  .page-about .chapter {
    padding: 48px 0;
  }

  .page-about .chapter p {
    font-size: 1rem;
    max-width: 62ch;
  }

  .page-about .seasons {
    max-width: 62ch;
  }

  .page-about .closing {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: stretch;
  }

  .page-about .closing__text {
    padding: 48px 42px;
    display: flex;
    flex-direction: column;
    justify-content: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .board-btn,
  .page-about .rail-list a,
  .page-about .about-toggle {
    transition: none;
  }
}
<<<END>>>