.page-about {
  --about-rail: 190px;
  background: var(--paper);
}

.page-about .about-hero {
  padding: 34px 0 40px;
  border-bottom: 1px solid var(--grid);
}

.page-about .about-hero h1 {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.9rem, 6.2vw, 3.3rem);
  line-height: 1.12;
  letter-spacing: -0.02em;
  color: var(--ink);
  max-width: 20ch;
}

.page-about .lede {
  margin: 22px 0 0;
  font-size: 1rem;
  line-height: 1.8;
  color: var(--ink-soft);
  max-width: 62ch;
}

.page-about .about-facts {
  list-style: none;
  margin: 26px 0 0;
  padding: 18px 0 0;
  border-top: 1px solid var(--grid);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px 18px;
}

.page-about .about-facts b {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--ink);
  letter-spacing: -0.01em;
}

.page-about .about-facts span {
  display: block;
  margin-top: 4px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  color: var(--tag);
}

.page-about .about-sec {
  padding: 40px 0;
  border-bottom: 1px solid var(--grid);
}

.page-about .about-sec:last-of-type {
  border-bottom: 0;
}

.page-about .sec-rail {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 16px;
  font-family: var(--font-mono);
}

.page-about .rail-num {
  font-size: 0.82rem;
  letter-spacing: 0.16em;
  color: var(--signal);
}

.page-about .rail-kicker {
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  color: var(--tag);
}

.page-about .rail-note {
  flex-basis: 100%;
  margin: 0;
  font-size: 0.74rem;
  line-height: 1.7;
  letter-spacing: 0.04em;
  color: var(--tag);
}

.page-about .sec-body h2 {
  margin: 0 0 18px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.45rem, 4.6vw, 2rem);
  line-height: 1.25;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.page-about .sec-body > p {
  margin: 0 0 15px;
  font-size: 1rem;
  line-height: 1.8;
  color: var(--ink-soft);
  max-width: 68ch;
}

.page-about .img-frame {
  margin: 26px 0 10px;
}

.page-about .img-caption {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  line-height: 1.7;
  letter-spacing: 0.04em;
  color: var(--tag);
}

/* 城市网格地图 */
.page-about .cmap-wrap {
  margin: 28px 0 0;
}

.page-about .cmap {
  display: block;
  width: 100%;
  height: auto;
  background: var(--paper);
  border: 1px solid var(--grid);
}

.page-about .cm-grid-line {
  fill: none;
  stroke: var(--grid);
  stroke-width: 1;
}

.page-about .cm-box {
  fill: none;
  stroke: var(--grid-strong);
  stroke-width: 1;
  stroke-dasharray: 4 5;
  transition: stroke 0.2s ease, fill 0.2s ease;
}

.page-about .cm-region {
  cursor: default;
  outline: none;
}

.page-about .cm-region:hover .cm-box,
.page-about .cm-region:focus .cm-box {
  stroke: var(--signal);
  stroke-dasharray: none;
  fill: rgba(255, 107, 53, 0.05);
}

.page-about .cm-label {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.12em;
  fill: var(--ink);
}

.page-about .cm-dot {
  fill: var(--mist);
  stroke: var(--grid-strong);
  stroke-width: 1;
  transition: fill 0.2s ease, stroke 0.2s ease;
}

.page-about .cm-region:hover .cm-dot,
.page-about .cm-region:focus .cm-dot {
  fill: var(--ice);
  stroke: var(--signal);
}

.page-about .cm-tip {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  fill: var(--signal);
  opacity: 0;
  transition: opacity 0.2s ease;
}

.page-about .cm-region:hover .cm-tip,
.page-about .cm-region:focus .cm-tip {
  opacity: 1;
}

.page-about .cm-hrb {
  outline: none;
}

.page-about .cm-hrb-dot {
  fill: var(--signal);
  stroke: var(--signal);
  stroke-width: 1;
}

.page-about .cm-hrb-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  fill: var(--ink);
}

.page-about .cm-hrb:focus .cm-hrb-label,
.page-about .cm-hrb:hover .cm-hrb-label {
  fill: var(--signal);
}

/* 纵向时间轴 */
.page-about .axis {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
}

.page-about .axis-item {
  position: relative;
  padding: 0 0 26px 28px;
  border-left: 1px solid var(--grid);
  outline: none;
}

.page-about .axis-item:last-child {
  padding-bottom: 0;
  border-left-color: transparent;
}

.page-about .axis-item::before {
  content: "";
  position: absolute;
  left: -5px;
  top: 7px;
  width: 9px;
  height: 9px;
  background: var(--paper);
  border: 1px solid var(--grid-strong);
  transition: background 0.2s ease, border-color 0.2s ease;
}

.page-about .axis-item:hover::before,
.page-about .axis-item:focus-visible::before {
  background: var(--signal);
  border-color: var(--signal);
}

.page-about .axis-item:focus-visible {
  outline: 2px solid var(--ice);
  outline-offset: 4px;
}

.page-about .axis-year {
  display: inline-block;
  margin-bottom: 6px;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.16em;
  color: var(--signal);
}

.page-about .axis-body h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.05rem;
  line-height: 1.45;
  color: var(--ink);
}

.page-about .axis-body p {
  margin: 0;
  font-size: 0.95rem;
  line-height: 1.78;
  color: var(--ink-soft);
  max-width: 60ch;
}

.page-about .axis-body .axis-more {
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  font-size: 0.88rem;
  line-height: 1.75;
  color: var(--tag);
  transition: max-height 0.3s ease, opacity 0.3s ease, margin 0.3s ease;
}

.page-about .axis-item:hover .axis-more,
.page-about .axis-item:focus-within .axis-more,
.page-about .axis-item:focus-visible .axis-more {
  max-height: 9rem;
  opacity: 1;
  margin-top: 8px;
}

/* 便签 */
.page-about .datanote {
  position: relative;
  margin: 26px 0 8px;
  padding: 16px 18px;
  max-width: 640px;
  background: var(--note);
  border: 1px solid rgba(180, 83, 9, 0.28);
  border-radius: var(--note-radius);
}

.page-about .datanote::before {
  content: "";
  position: absolute;
  top: -6px;
  left: 20px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--signal);
}

.page-about .datanote summary {
  cursor: pointer;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  color: var(--ink);
}

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

.page-about .datanote summary::after {
  content: "（展开）";
  color: var(--warn);
  font-weight: 400;
}

.page-about .datanote[open] summary::after {
  content: "（收起）";
}

.page-about .datanote summary:focus-visible {
  outline: 2px solid var(--ice);
  outline-offset: 3px;
}

.page-about .datanote p {
  margin: 12px 0 0;
  font-size: 0.9rem;
  line-height: 1.75;
  color: var(--ink);
}

/* 深色数据面板 */
.page-about .acclaim-panel {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  margin: 24px 0;
  background: var(--grid);
  border: 1px solid var(--grid);
}

.page-about .acclaim-panel > div {
  padding: 22px 18px;
  background: var(--pine);
  color: var(--mist);
}

.page-about .acclaim-panel b {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.9rem;
  font-weight: 600;
  line-height: 1;
  color: var(--ice);
}

.page-about .acclaim-panel span {
  display: block;
  margin-top: 8px;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.06em;
  color: rgba(244, 246, 247, 0.74);
}

/* 底部索引 */
.page-about .about-next {
  padding: 40px 0 56px;
  border-top: 2px solid var(--signal);
}

.page-about .about-next .eyebrow {
  margin-bottom: 16px;
}

.page-about .next-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .next-list li {
  border-top: 1px solid var(--grid);
}

.page-about .next-list li:first-child {
  border-top: 0;
}

.page-about .next-list a {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  padding: 15px 2px;
  text-decoration: none;
  font-size: 0.98rem;
  line-height: 1.5;
  color: var(--ink);
  transition: color 0.2s ease, padding-left 0.2s ease;
}

.page-about .next-list a:hover,
.page-about .next-list a:focus-visible {
  color: var(--signal);
  padding-left: 10px;
}

.page-about .next-list a:focus-visible {
  outline: 2px solid var(--ice);
  outline-offset: 2px;
}

.page-about .next-num {
  flex: none;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.14em;
  color: var(--tag);
}

@media (min-width: 900px) {
  .page-about .about-hero {
    display: grid;
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    gap: 56px;
    align-items: end;
    padding: 64px 0 56px;
  }

  .page-about .about-hero-side {
    padding-left: 40px;
    border-left: 1px solid var(--grid);
  }

  .page-about .lede {
    margin-top: 0;
  }

  .page-about .about-facts {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px 24px;
  }

  .page-about .about-sec {
    display: grid;
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: 48px;
    padding: 64px 0;
  }

  .page-about .sec-rail {
    flex-direction: column;
    align-items: flex-start;
    align-self: start;
    gap: 6px;
    margin-bottom: 0;
    padding-top: 14px;
    border-top: 2px solid var(--signal);
  }

  .page-about .rail-note {
    flex-basis: auto;
    margin-top: 14px;
  }

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

  .page-about .acclaim-panel > div {
    padding: 26px 22px;
  }

  .page-about .axis-item {
    padding-left: 34px;
  }

  .page-about .about-next {
    padding: 56px 0 72px;
  }
}
<<<END>>>