.page-about {
  --ab-line: rgba(201, 211, 221, 0.18);
  --ab-card: rgba(18, 54, 90, 0.72);
  background: var(--navy);
  color: var(--mist);
  font-family: var(--font-body);
  padding: 16px 0 56px;
}

.page-about .wrap {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 18px;
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--grey);
  padding: 8px 0 4px;
}

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

.page-about .breadcrumbs a:hover {
  color: var(--lime);
}

.page-about .crumb-sep {
  color: var(--steel);
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  display: grid;
  gap: 20px;
  margin-top: 14px;
  padding-bottom: 26px;
  border-bottom: 3px solid var(--steel);
}

.page-about .ab-hero-copy {
  border-left: 4px solid var(--lime);
  padding-left: 14px;
}

.page-about .ab-hero h1 {
  font-size: clamp(30px, 6vw, 54px);
  line-height: 1.1;
  font-weight: 800;
  letter-spacing: -0.01em;
  margin: 10px 0 14px;
  color: var(--mist);
}

.page-about .ab-lede {
  font-size: 16px;
  line-height: 1.72;
  color: var(--grey);
  max-width: 58ch;
  margin: 0;
}

.page-about .ab-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
}

.page-about .ab-hero-panel {
  background: linear-gradient(158deg, rgba(18, 54, 90, 0.92), rgba(6, 18, 38, 0.96));
  border: 3px solid var(--steel);
  border-radius: var(--radius);
  box-shadow: 6px 6px 0 var(--midnight);
  padding: 16px;
}

.page-about .ab-panel-k {
  margin: 0 0 12px;
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--lime);
}

.page-about .ab-panel-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px 10px;
}

.page-about .ab-panel-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(24px, 7vw, 32px);
  font-weight: 700;
  line-height: 1;
  color: var(--lime);
}

.page-about .ab-panel-u {
  font-size: 0.5em;
  margin-left: 2px;
}

.page-about .ab-panel-t {
  display: block;
  margin-top: 5px;
  font-size: 12px;
  line-height: 1.4;
  color: var(--grey);
}

.page-about .ab-panel-foot {
  margin: 16px 0 0;
  padding-top: 12px;
  border-top: 1px solid var(--steel);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--grey);
}

/* ---------- 主体：索引 + 章节 ---------- */
.page-about .ab-body {
  display: grid;
  gap: 26px;
  margin-top: 30px;
}

.page-about .ab-rail-title {
  margin: 0 0 10px;
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--grey);
}

.page-about .ab-rail-list {
  list-style: none;
  margin: 0;
  padding: 0 0 8px;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  max-width: 100%;
}

.page-about .ab-rail-list::-webkit-scrollbar {
  height: 0;
}

.page-about .ab-rail-link {
  display: flex;
  align-items: center;
  gap: 8px;
  white-space: nowrap;
  padding: 8px 12px;
  border: 2px solid var(--steel);
  border-radius: var(--radius);
  background: rgba(18, 54, 90, 0.5);
  color: var(--grey);
  font-size: 13px;
  text-decoration: none;
  transition: border-color 0.16s ease, color 0.16s ease, background 0.16s ease;
}

.page-about .ab-rail-num {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  color: var(--lime);
}

.page-about .ab-rail-link:hover,
.page-about .ab-rail-link:focus-visible {
  border-color: var(--lime);
  color: var(--mist);
  background: rgba(30, 54, 0, 0.6);
}

.page-about .ab-rail-link:hover .ab-rail-num,
.page-about .ab-rail-link:focus-visible .ab-rail-num {
  color: var(--lime);
}

/* ---------- 章节 ---------- */
.page-about .ab-chapters {
  display: flex;
  flex-direction: column;
  gap: 48px;
  min-width: 0;
}

.page-about .ab-chapter {
  scroll-margin-top: calc(var(--command) + 24px);
}

.page-about .ab-chapter-head {
  display: flex;
  align-items: center;
  gap: 12px;
  padding-bottom: 10px;
  margin-bottom: 16px;
  border-bottom: 3px solid var(--steel);
}

.page-about .ab-chapter-idx {
  flex: none;
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--lime);
  background: var(--lime-deep);
  border: 2px solid var(--lime);
  border-radius: 2px;
  padding: 3px 8px;
}

.page-about .ab-chapter h2 {
  font-size: clamp(20px, 2.7vw, 30px);
  line-height: 1.24;
  font-weight: 800;
  margin: 0;
  color: var(--mist);
}

.page-about .ab-chapter > p {
  margin: 0 0 18px;
  font-size: 16px;
  line-height: 1.76;
  color: rgba(244, 247, 243, 0.86);
  max-width: 64ch;
}

/* ---------- 图片 ---------- */
.page-about .ab-figure {
  margin: 0 0 20px;
  border: 3px solid var(--steel);
  border-radius: var(--radius);
  box-shadow: 6px 6px 0 var(--midnight);
  overflow: hidden;
  background: var(--midnight);
}

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

.page-about .ab-figure--tall {
  max-width: 420px;
}

/* ---------- 信息卡 ---------- */
.page-about .ab-tiles {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

.page-about .ab-tile {
  background: var(--ab-card);
  border: 3px solid var(--steel);
  border-radius: var(--radius);
  box-shadow: 4px 4px 0 var(--midnight);
  padding: 15px 16px;
  transition: transform 0.18s ease, border-color 0.18s ease;
}

.page-about .ab-tile:hover {
  transform: translateY(-2px);
  border-color: var(--lime);
}

.page-about .ab-tile-k {
  display: inline-block;
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--lime);
  background: var(--lime-deep);
  border-radius: 2px;
  padding: 2px 7px;
}

.page-about .ab-tile h3 {
  font-size: 17px;
  line-height: 1.4;
  font-weight: 700;
  margin: 10px 0 6px;
  color: var(--mist);
}

.page-about .ab-tile p {
  margin: 0;
  font-size: 14px;
  line-height: 1.68;
  color: var(--grey);
}

/* ---------- 时间轴 ---------- */
.page-about .ab-timeline {
  list-style: none;
  margin: 0;
  padding: 2px 0 2px 22px;
  position: relative;
}

.page-about .ab-timeline::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 10px;
  bottom: 10px;
  width: 2px;
  background: linear-gradient(180deg, var(--lime), var(--steel) 72%, rgba(18, 54, 90, 0));
}

.page-about .ab-timeline li {
  position: relative;
  padding: 0 0 24px;
}

.page-about .ab-timeline li::before {
  content: "";
  position: absolute;
  left: -20px;
  top: 5px;
  width: 12px;
  height: 12px;
  background: var(--lime);
  border: 2px solid var(--midnight);
  border-radius: 2px;
  box-shadow: 0 0 0 3px rgba(198, 255, 0, 0.12);
}

.page-about .ab-timeline li:last-child {
  padding-bottom: 0;
}

.page-about .ab-timeline h3 {
  margin: 0 0 6px;
  font-size: 17px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--mist);
}

.page-about .ab-timeline p {
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--grey);
  max-width: 60ch;
}

/* ---------- 覆盖地图 ---------- */
.page-about .ab-map-wrap {
  margin: 0 0 20px;
  border: 3px solid var(--steel);
  border-radius: var(--radius);
  box-shadow: 6px 6px 0 var(--midnight);
  background: var(--midnight);
  overflow: hidden;
}

.page-about .ab-map {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  transition: opacity 0.2s ease;
}

.page-about .ab-map-wrap:hover .ab-map {
  opacity: 0.9;
}

.page-about .ab-legend {
  list-style: none;
  margin: 0;
  padding: 12px 14px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 20px;
  border-top: 1px solid var(--steel);
}

.page-about .ab-legend li {
  display: flex;
  align-items: center;
  gap: 7px;
  font-size: 12px;
  color: var(--grey);
}

.page-about .ab-dot {
  width: 10px;
  height: 10px;
  border-radius: 2px;
  flex: none;
}

.page-about .ab-dot--lime {
  background: var(--lime);
}

.page-about .ab-dot--cyan {
  background: transparent;
  border: 2px solid var(--cyan);
}

/* ---------- 规模数据 ---------- */
.page-about .ab-stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.page-about .ab-stat {
  background: var(--midnight);
  border: 3px solid var(--steel);
  border-radius: var(--radius);
  padding: 13px 14px;
}

.page-about .ab-stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(26px, 5vw, 38px);
  font-weight: 700;
  line-height: 1;
  color: var(--lime);
}

.page-about .ab-stat-u {
  font-size: 0.5em;
  margin-left: 2px;
}

.page-about .ab-stat-l {
  display: block;
  margin-top: 7px;
  font-size: 12px;
  line-height: 1.5;
  color: var(--grey);
}

/* ---------- 要点清单 ---------- */
.page-about .ab-notes {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .ab-notes li {
  position: relative;
  padding: 13px 15px 13px 34px;
  background: rgba(18, 54, 90, 0.42);
  border-left: 3px solid var(--steel);
  border-radius: 0 var(--radius) var(--radius) 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--grey);
}

.page-about .ab-notes li::before {
  content: "";
  position: absolute;
  left: 13px;
  top: 20px;
  width: 8px;
  height: 8px;
  background: var(--cyan);
  border-radius: 1px;
}

.page-about .ab-notes strong {
  display: block;
  margin-bottom: 3px;
  font-size: 15px;
  color: var(--mist);
}

.page-about .ab-notes--accent li {
  border-left-color: var(--lime);
  background: rgba(30, 54, 0, 0.38);
}

.page-about .ab-notes--accent li::before {
  background: var(--lime);
}

/* ---------- 入口卡 ---------- */
.page-about .ab-links {
  list-style: none;
  margin: 0 0 24px;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.page-about .ab-link-card {
  display: grid;
  grid-template-columns: auto 1fr auto;
  grid-template-areas:
    "k title arrow"
    "k desc arrow";
  align-items: center;
  gap: 2px 12px;
  padding: 14px 16px;
  background: var(--ab-card);
  border: 3px solid var(--steel);
  border-radius: var(--radius);
  box-shadow: 4px 4px 0 var(--midnight);
  text-decoration: none;
  color: inherit;
  transition: transform 0.18s ease, border-color 0.18s ease, box-shadow 0.18s ease;
}

.page-about .ab-link-card:hover,
.page-about .ab-link-card:focus-visible {
  transform: translateY(-2px);
  border-color: var(--lime);
  box-shadow: 6px 6px 0 var(--midnight);
}

.page-about .ab-link-k {
  grid-area: k;
  align-self: start;
  font-size: 12px;
  font-weight: 700;
  color: var(--lime);
  border: 2px solid var(--steel);
  border-radius: 2px;
  padding: 2px 6px;
}

.page-about .ab-link-card strong {
  grid-area: title;
  font-size: 16px;
  font-weight: 700;
  color: var(--mist);
}

.page-about .ab-link-d {
  grid-area: desc;
  font-size: 13px;
  line-height: 1.6;
  color: var(--grey);
}

.page-about .ab-link-arrow {
  grid-area: arrow;
  font-family: var(--font-mono);
  font-size: 18px;
  color: var(--lime);
}

/* ---------- 费用速查 ---------- */
.page-about .ab-fee {
  border: 3px solid var(--lime);
  border-radius: var(--radius);
  background: linear-gradient(140deg, rgba(30, 54, 0, 0.72), rgba(6, 18, 38, 0.94));
  box-shadow: 6px 6px 0 var(--midnight);
  padding: 15px 16px;
}

.page-about .ab-fee-title {
  margin: 0 0 12px;
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--lime);
}

.page-about .ab-fee-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 8px;
}

.page-about .ab-fee-list a {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: baseline;
  gap: 4px 14px;
  padding: 9px 11px;
  border: 2px solid var(--steel);
  border-radius: 2px;
  background: rgba(10, 31, 61, 0.7);
  text-decoration: none;
  transition: border-color 0.16s ease, background 0.16s ease;
}

.page-about .ab-fee-list a:hover,
.page-about .ab-fee-list a:focus-visible {
  border-color: var(--lime);
  background: rgba(30, 54, 0, 0.5);
}

.page-about .ab-fee-list span {
  font-size: 13px;
  color: var(--grey);
}

.page-about .ab-fee-list strong {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 700;
  color: var(--lime);
}

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

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

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

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

@media (min-width: 900px) {
  .page-about {
    padding-bottom: 72px;
  }

  .page-about .wrap {
    padding: 0 40px;
  }

  .page-about .ab-hero {
    grid-template-columns: minmax(0, 1.4fr) minmax(280px, 0.8fr);
    gap: 34px;
    align-items: start;
    margin-top: 18px;
    padding-bottom: 34px;
  }

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

  .page-about .ab-figure--wide img {
    max-height: 460px;
  }

  .page-about .ab-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 1000px) {
  .page-about .ab-body {
    grid-template-columns: 176px minmax(0, 1fr);
    gap: 44px;
    margin-top: 36px;
  }

  .page-about .ab-rail {
    position: sticky;
    top: calc(var(--command) + 24px);
    align-self: start;
  }

  .page-about .ab-rail-title {
    margin-bottom: 14px;
  }

  .page-about .ab-rail-list {
    display: block;
    overflow: visible;
    padding: 0;
    position: relative;
  }

  .page-about .ab-rail-list::before {
    content: "";
    position: absolute;
    left: 11px;
    top: 12px;
    bottom: 12px;
    width: 2px;
    background: linear-gradient(180deg, rgba(198, 255, 0, 0.7), rgba(18, 54, 90, 0.2));
  }

  .page-about .ab-rail-link {
    display: grid;
    grid-template-columns: 24px minmax(0, 1fr);
    gap: 10px;
    align-items: center;
    white-space: normal;
    padding: 7px 0;
    background: none;
    border: 0;
    border-radius: 0;
    font-size: 12.5px;
    line-height: 1.45;
  }

  .page-about .ab-rail-link:hover,
  .page-about .ab-rail-link:focus-visible {
    background: none;
    color: var(--lime);
  }

  .page-about .ab-rail-num {
    width: 24px;
    height: 24px;
    display: grid;
    place-items: center;
    font-size: 11px;
    border: 2px solid var(--steel);
    border-radius: 2px;
    background: var(--navy);
    transition: background 0.16s ease, color 0.16s ease, border-color 0.16s ease;
  }

  .page-about .ab-rail-link:hover .ab-rail-num,
  .page-about .ab-rail-link:focus-visible .ab-rail-num {
    background: var(--lime);
    color: var(--lime-deep);
    border-color: var(--lime);
  }

  .page-about .ab-links {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px;
  }
}

@media (min-width: 1280px) {
  .page-about .wrap {
    padding: 0 48px;
  }

  .page-about .ab-body {
    grid-template-columns: 196px minmax(0, 1fr);
    gap: 52px;
  }

  .page-about .ab-chapters {
    gap: 56px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-tile,
  .page-about .ab-link-card,
  .page-about .ab-map {
    transition: none;
  }

  .page-about .ab-tile:hover,
  .page-about .ab-link-card:hover,
  .page-about .ab-link-card:focus-visible {
    transform: none;
  }
}
<<<END>>>