.page-about {
  --about-rail-w: 244px;
  --about-ink-soft: rgba(37, 28, 22, 0.74);
  --about-hair: rgba(37, 28, 22, 0.16);
  background: var(--graphite-900);
  color: var(--text);
  padding-bottom: clamp(48px, 7vw, 96px);
}

.page-about .about-mast {
  position: relative;
  overflow: hidden;
  padding: clamp(20px, 3.6vw, 34px) 0 clamp(40px, 6vw, 72px);
  background:
    radial-gradient(120% 100% at 88% -10%, rgba(11, 94, 215, 0.42), transparent 62%),
    radial-gradient(80% 70% at 0% 110%, rgba(22, 224, 255, 0.12), transparent 60%),
    var(--graphite-900);
  border-bottom: 1px solid var(--line-blue);
}

.page-about .about-mast::after {
  content: "";
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(116deg, rgba(174, 183, 194, 0.09) 0 1px, transparent 1px 28px);
  pointer-events: none;
}

.page-about .about-mast > .container {
  position: relative;
  z-index: 1;
}

.page-about .breadcrumb-link {
  color: var(--text-dim);
}

.page-about .breadcrumb-link[aria-current="page"] {
  color: var(--cyan);
}

.page-about .about-mast-grid {
  display: grid;
  gap: clamp(26px, 4vw, 44px);
  margin-top: clamp(22px, 3.6vw, 38px);
}

.page-about .about-mast h1 {
  font-family: var(--font-display);
  font-size: clamp(38px, 8.4vw, 76px);
  line-height: 0.94;
  letter-spacing: -0.04em;
  font-weight: 800;
  margin: 14px 0 0;
  color: #fff;
}

.page-about .about-lead {
  max-width: 48ch;
  margin-top: 20px;
  font-size: clamp(15px, 1.7vw, 17px);
  line-height: 1.8;
  color: var(--text-dim);
}

.page-about .about-mast-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.page-about .about-mast-stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .mast-stat {
  background: var(--graphite-800);
  padding: 16px 14px 14px;
}

.page-about .stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(24px, 3.6vw, 34px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--yellow);
}

.page-about .stat-label {
  display: block;
  margin-top: 8px;
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--mist);
}

/* ---------- 画册跨页 ---------- */

.page-about .about-sheet {
  margin-top: clamp(24px, 4vw, 44px);
  background: var(--paper);
  color: var(--paper-ink);
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.45);
}

.page-about .about-rail {
  background: var(--graphite-800);
  color: var(--text);
  padding: 20px 18px 24px;
  border-bottom: 2px solid var(--blue);
}

.page-about .about-rail-cover {
  margin: 0 0 18px;
  overflow: hidden;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 18px), calc(100% - 18px) 100%, 0 100%);
}

.page-about .about-rail-cover img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.page-about .rail-title {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .rail-nav ol {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .rail-link {
  display: flex;
  gap: 10px;
  align-items: baseline;
  padding: 8px 0;
  border-bottom: 1px solid rgba(174, 183, 194, 0.14);
  color: var(--text-dim);
  font-size: 13px;
  line-height: 1.45;
  text-decoration: none;
  transition: color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .rail-link:hover {
  color: var(--cyan);
  transform: translateX(4px);
}

.page-about .rail-link:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

.page-about .rail-num {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--yellow);
}

.page-about .rail-years {
  margin-top: 22px;
}

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

.page-about .rail-year-list li {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 5px 0;
  font-size: 12.5px;
  color: var(--mist);
}

.page-about .rail-year {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--cyan);
  letter-spacing: 0.04em;
}

.page-about .about-body {
  padding: clamp(22px, 4vw, 54px) clamp(18px, 4vw, 52px) clamp(28px, 5vw, 60px);
}

.page-about .about-chapter {
  padding-block: clamp(26px, 4vw, 46px);
  border-top: 1px solid var(--about-hair);
}

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

.page-about .chapter-head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 16px;
}

.page-about .chapter-num {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--blue);
}

.page-about .about-chapter h2 {
  font-family: var(--font-display);
  font-size: clamp(24px, 3.6vw, 38px);
  line-height: 1.08;
  letter-spacing: -0.03em;
  font-weight: 800;
  margin: 0;
  color: var(--paper-ink);
}

.page-about .about-chapter p {
  max-width: 64ch;
  margin: 0 0 14px;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--about-ink-soft);
}

.page-about .about-chapter h3 {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-size: 19px;
  letter-spacing: -0.01em;
  font-weight: 700;
  color: var(--paper-ink);
}

/* 01 体验清单 */

.page-about .exp-list {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  border-top: 1px solid var(--about-hair);
}

.page-about .exp-item {
  display: grid;
  gap: 4px;
  padding: 13px 0;
  border-bottom: 1px solid var(--about-hair);
}

.page-about .exp-key {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--paper-ink);
}

.page-about .exp-val {
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--about-ink-soft);
}

.page-about .fact-strip {
  list-style: none;
  display: grid;
  gap: 1px;
  margin: 24px 0 0;
  padding: 0;
  background: var(--about-hair);
  border: 1px solid var(--about-hair);
}

.page-about .fact-strip li {
  background: rgba(255, 255, 255, 0.55);
  padding: 14px 16px;
}

.page-about .fact-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 22px;
  line-height: 1.1;
  color: var(--blue);
}

.page-about .fact-txt {
  display: block;
  margin-top: 5px;
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--about-ink-soft);
}

/* 02 坐标索引 */

.page-about .coverage-grid {
  display: grid;
  gap: clamp(20px, 3vw, 30px);
  margin-top: 22px;
}

.page-about .coverage-grid .media-frame {
  background: var(--graphite-800);
  border-color: rgba(11, 94, 215, 0.5);
}

.page-about .coverage-grid .media-caption {
  color: var(--mist);
}

.page-about .legend {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 14px;
  margin: 0 0 16px;
  padding: 0;
}

.page-about .legend-item {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 6px 11px;
  border: 1px solid var(--about-hair);
  font-size: 12.5px;
  color: var(--about-ink-soft);
  transition: border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-about .legend-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--blue);
}

.page-about .legend-item--partner .legend-dot {
  background: var(--cyan);
}

.page-about .legend-item--new .legend-dot {
  background: var(--orange);
}

.page-about .legend-count {
  font-family: var(--font-mono);
  color: var(--paper-ink);
}

.page-about .coord-table {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--about-hair);
}

.page-about .coord-row {
  display: grid;
  gap: 3px 12px;
  padding: 12px 10px 12px 0;
  border-bottom: 1px solid var(--about-hair);
  border-left: 3px solid transparent;
  transition: background-color var(--dur) var(--ease), border-left-color var(--dur) var(--ease), padding-left var(--dur) var(--ease);
}

.page-about .coord-row:hover,
.page-about .coord-row:focus-visible,
.page-about .coord-row:focus-within {
  background: rgba(11, 94, 215, 0.07);
  border-left-color: var(--blue);
  padding-left: 10px;
  outline: none;
}

.page-about .coord-row--new:hover,
.page-about .coord-row--new:focus-visible,
.page-about .coord-row--new:focus-within {
  background: rgba(255, 90, 31, 0.09);
  border-left-color: var(--orange);
}

.page-about .coord-key {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--blue);
}

.page-about .coord-row--new .coord-key {
  color: var(--orange);
}

.page-about .coord-label {
  font-family: var(--font-display);
  font-size: 16.5px;
  font-weight: 700;
  color: var(--paper-ink);
}

.page-about .coord-note {
  font-size: 14px;
  line-height: 1.7;
  color: var(--about-ink-soft);
}

.page-about .coverage-grid:has(.coord-row--direct:hover) .legend-item--direct,
.page-about .coverage-grid:has(.coord-row--partner:hover) .legend-item--partner,
.page-about .coverage-grid:has(.coord-row--new:hover) .legend-item--new {
  border-color: var(--blue);
  background: rgba(11, 94, 215, 0.08);
}

.page-about .coverage-tip {
  margin: 18px 0 0;
  padding-left: 14px;
  border-left: 2px solid var(--cyan);
  font-size: 14px;
  line-height: 1.75;
  color: var(--about-ink-soft);
}

/* 03 版本时间轴 */

.page-about .version-line {
  list-style: none;
  margin: 24px 0 0;
  padding: 0 0 0 22px;
  border-left: 1px solid var(--about-hair);
}

.page-about .version-item {
  position: relative;
  padding: 0 0 22px 0;
}

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

.page-about .version-node {
  position: absolute;
  left: -34px;
  top: 2px;
  display: grid;
  place-items: center;
  width: 24px;
  height: 24px;
  border: 1px solid var(--yellow);
  background: var(--paper);
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--paper-ink);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 6px), calc(100% - 6px) 100%, 0 100%);
}

.page-about .version-item--current .version-node {
  background: var(--orange);
  border-color: var(--orange);
  color: #fff;
}

.page-about .version-body {
  padding: 0 0 0 4px;
}

.page-about .version-more {
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  margin-bottom: 0 !important;
  transition: max-height 220ms var(--ease), opacity 180ms var(--ease), margin-bottom 220ms var(--ease);
}

.page-about .version-item:hover .version-more,
.page-about .version-item:focus .version-more,
.page-about .version-item:focus-within .version-more {
  max-height: 220px;
  opacity: 1;
  margin-bottom: 14px !important;
}

.page-about .version-item:focus {
  outline: none;
}

.page-about .version-item:focus-visible .version-body h3 {
  color: var(--blue);
}

.page-about .version-figure {
  margin-top: 26px;
  background: var(--graphite-800);
  border-color: rgba(255, 210, 63, 0.45);
}

.page-about .version-figure .media-caption {
  color: var(--mist);
}

/* 04 团队 */

.page-about .team-rows {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
}

.page-about .team-row {
  display: grid;
  gap: 6px 20px;
  padding: 16px 0;
  border-bottom: 1px solid var(--about-hair);
}

.page-about .team-row:first-child {
  border-top: 1px solid var(--about-hair);
}

.page-about .team-num {
  font-family: var(--font-mono);
  font-size: 34px;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--blue);
}

.page-about .team-text h3 {
  margin-bottom: 4px;
}

.page-about .team-text p {
  margin: 0;
  font-size: 14.5px;
}

.page-about .standard-list {
  list-style: none;
  margin: 26px 0 0;
  padding: 18px 18px 6px;
  background: rgba(11, 94, 215, 0.06);
  border-left: 3px solid var(--blue);
}

.page-about .standard-list li {
  position: relative;
  padding: 0 0 12px 18px;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--about-ink-soft);
}

.page-about .std-mark {
  position: absolute;
  left: 0;
  top: 9px;
  width: 7px;
  height: 7px;
  background: var(--blue);
}

/* 05 生态 */

.page-about .eco-grid {
  display: grid;
  gap: 1px;
  margin-top: 24px;
  background: var(--about-hair);
  border: 1px solid var(--about-hair);
}

.page-about .eco-cell {
  background: rgba(255, 255, 255, 0.5);
  padding: 20px 18px;
}

.page-about .eco-cell--note {
  background: var(--graphite-800);
  color: var(--text);
}

.page-about .eco-kicker {
  margin: 0 0 6px !important;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--blue) !important;
}

.page-about .eco-cell--note .eco-kicker {
  color: var(--cyan) !important;
}

.page-about .eco-big {
  margin: 0 0 8px !important;
  font-family: var(--font-mono);
  font-size: 44px;
  line-height: 1;
  letter-spacing: -0.04em;
  color: var(--paper-ink) !important;
}

.page-about .eco-txt {
  margin: 0 !important;
  font-size: 14px;
  line-height: 1.75;
  color: var(--about-ink-soft) !important;
}

.page-about .eco-cell--note .eco-txt {
  color: var(--text-dim) !important;
}

.page-about .eco-txt--strong {
  color: var(--paper) !important;
  font-size: 16px !important;
  line-height: 1.6 !important;
  margin-bottom: 8px !important;
}

/* 06 路线 */

.page-about .route-list {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .route-link {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 4px 14px;
  padding: 15px 16px;
  background: rgba(255, 255, 255, 0.55);
  border: 1px solid var(--about-hair);
  color: var(--paper-ink);
  text-decoration: none;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 12px), calc(100% - 12px) 100%, 0 100%);
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-about .route-link:hover {
  transform: translate(4px, -3px);
  border-color: var(--blue);
  background: rgba(11, 94, 215, 0.08);
}

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

.page-about .route-num {
  grid-row: span 2;
  align-self: start;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--blue);
  padding-top: 4px;
}

.page-about .route-name {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.page-about .route-desc {
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--about-ink-soft);
}

.page-about .route-item--accent .route-link {
  background: rgba(255, 90, 31, 0.09);
  border-color: rgba(255, 90, 31, 0.4);
}

.page-about .route-item--accent .route-num {
  color: var(--orange);
}

.page-about .route-foot {
  margin-top: 20px;
  font-size: 14px;
}

.page-about .inline-link {
  color: var(--blue);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .inline-link:hover {
  color: var(--orange);
}

/* ---------- 响应式 ---------- */

@media (min-width: 620px) {
  .page-about .exp-item {
    grid-template-columns: 132px minmax(0, 1fr);
    gap: 16px;
    align-items: baseline;
  }

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

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

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

@media (min-width: 900px) {
  .page-about .about-mast-grid {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 0.65fr);
    align-items: end;
  }

  .page-about .team-row {
    grid-template-columns: 128px minmax(0, 1fr);
    align-items: baseline;
  }

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

@media (min-width: 960px) {
  .page-about .about-sheet {
    display: grid;
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--header-h) + var(--track-h) + 18px);
    border-bottom: 0;
    border-right: 2px solid var(--blue);
    padding: 24px 20px 28px;
  }

  .page-about .about-rail-cover {
    margin-bottom: 20px;
  }

  .page-about .coverage-grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    align-items: start;
  }

  .page-about .about-chapter h2 {
    font-size: clamp(28px, 3vw, 38px);
  }
}

@media (min-width: 1180px) {
  .page-about .about-body {
    padding-left: clamp(40px, 4vw, 64px);
    padding-right: clamp(40px, 4vw, 64px);
  }

  .page-about .coord-row {
    grid-template-columns: 96px minmax(0, 180px) minmax(0, 1fr);
    align-items: baseline;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .rail-link,
  .page-about .coord-row,
  .page-about .route-link,
  .page-about .version-more {
    transition: none !important;
  }

  .page-about .rail-link:hover,
  .page-about .route-link:hover {
    transform: none;
  }
}
<<<END>>>