.page-about {
  --about-hair: rgba(140, 163, 184, 0.42);
  background-color: var(--night-800);
  color: var(--paper);
  overflow-x: clip;
}

.page-about a:focus-visible,
.page-about [tabindex]:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: calc(var(--u) * 4) 0 calc(var(--u) * 7);
  border-bottom: var(--border);
  background-color: var(--night-800);
  background-image:
    linear-gradient(to right, rgba(37, 59, 82, 0.45) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(37, 59, 82, 0.45) 1px, transparent 1px);
  background-size: 64px 64px;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: clamp(120px, 24vw, 300px);
  height: 100%;
  background: linear-gradient(180deg, rgba(255, 122, 45, 0.16), rgba(7, 20, 38, 0) 72%);
  clip-path: polygon(34% 0, 100% 0, 100% 100%, 0 100%);
  pointer-events: none;
}

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

.page-about .about-hero-inner > .breadcrumb {
  margin-bottom: calc(var(--u) * 4);
}

.page-about .about-hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: calc(var(--u) * 5);
  align-items: end;
}

.page-about .about-eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.16em;
  color: var(--orange);
  text-transform: uppercase;
}

.page-about .about-hero h1 {
  margin: calc(var(--u) * 2) 0 calc(var(--u) * 3);
  max-width: 17ch;
  font-size: var(--fs-h1);
  font-weight: 900;
  line-height: 1.04;
  letter-spacing: -0.015em;
}

.page-about .about-hl {
  color: var(--cyan);
  box-shadow: inset 0 -0.18em 0 rgba(57, 245, 200, 0.22);
}

.page-about .about-lead {
  margin: 0;
  max-width: 58ch;
  font-size: var(--fs-body);
  line-height: 1.75;
  color: rgba(244, 247, 250, 0.86);
}

.page-about .about-tags {
  display: flex;
  flex-wrap: wrap;
  gap: calc(var(--u) * 1);
  margin: calc(var(--u) * 3) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: calc(var(--u) * 1.5);
  margin-top: calc(var(--u) * 4);
}

.page-about .about-hero-figure {
  position: relative;
  margin: 0;
  border: 3px solid var(--ink);
  box-shadow: var(--shadow-hard);
  background: var(--night-900);
}

.page-about .about-hero-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  filter: saturate(0.88) contrast(1.12) brightness(0.76);
}

.page-about .about-hero-figure::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(158deg, rgba(57, 245, 200, 0.16), transparent 44%),
    linear-gradient(20deg, rgba(255, 122, 45, 0.16), transparent 38%);
  pointer-events: none;
}

.page-about .about-figure-cap {
  margin: calc(var(--u) * 1.5) 0 0;
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.06em;
  color: var(--cool);
}

/* ---------- 主体布局 ---------- */
.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: calc(var(--u) * 4);
  padding-top: calc(var(--u) * 6);
  padding-bottom: calc(var(--u) * 8);
}

.page-about .about-index-title {
  margin: 0 0 calc(var(--u) * 1.5);
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.18em;
  color: var(--cool);
}

.page-about .about-index-list {
  display: flex;
  gap: calc(var(--u) * 1);
  margin: 0;
  padding: 0 0 calc(var(--u) * 1);
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-index-link {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border: 1px solid var(--line-blue);
  color: var(--cool);
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  text-decoration: none;
  white-space: nowrap;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease), background 0.18s var(--ease);
}

.page-about .about-index-link:hover {
  color: var(--paper);
  border-color: var(--cyan);
}

.page-about .about-index-num {
  color: var(--orange);
  letter-spacing: 0.08em;
  transition: color 0.18s var(--ease);
}

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

/* ---------- 章节骨架 ---------- */
.page-about .about-chapter {
  padding-bottom: calc(var(--u) * 6);
}

.page-about .about-chapter + .about-chapter {
  border-top: 1px dashed var(--line-blue);
  padding-top: calc(var(--u) * 6);
}

.page-about .about-chapter-head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  align-items: baseline;
  gap: calc(var(--u) * 2);
  margin-bottom: calc(var(--u) * 4);
}

.page-about .about-chapter-num {
  padding: 2px 6px;
  border: 1px solid var(--orange);
  color: var(--orange);
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  line-height: 1.4;
  letter-spacing: 0.08em;
}

.page-about .about-chapter-head h2 {
  margin: 0;
  font-size: var(--fs-h2);
  font-weight: 900;
  line-height: 1.12;
  letter-spacing: -0.01em;
}

.page-about .about-chapter-lead {
  grid-column: 1 / -1;
  margin: calc(var(--u) * 1.5) 0 0;
  max-width: 62ch;
  font-size: var(--fs-body);
  line-height: 1.7;
  color: rgba(244, 247, 250, 0.78);
}

.page-about .about-prose p {
  margin: 0 0 calc(var(--u) * 2.5);
  font-size: var(--fs-body);
  line-height: 1.78;
  color: rgba(244, 247, 250, 0.88);
}

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

/* ---------- 01 起点 ---------- */
.page-about .about-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: calc(var(--u) * 4);
  align-items: start;
}

.page-about .about-quote {
  margin: 0;
  padding: calc(var(--u) * 3);
  background: var(--paper);
  color: var(--ink);
  border: 3px solid var(--ink);
  box-shadow: var(--shadow-hard-sm);
  transform: rotate(-0.9deg);
}

.page-about .about-quote p {
  margin: 0 0 calc(var(--u) * 2);
  font-size: var(--fs-h3);
  font-weight: 700;
  line-height: 1.5;
}

.page-about .about-quote cite {
  font-family: var(--font-mono);
  font-style: normal;
  font-size: var(--fs-mono);
  letter-spacing: 0.05em;
  color: #455a6b;
}

/* ---------- 02 体系条带 ---------- */
.page-about .about-bands {
  margin: 0 0 calc(var(--u) * 4);
  padding: 0;
  list-style: none;
}

.page-about .about-band {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: calc(var(--u) * 2) calc(var(--u) * 2.5);
  align-items: start;
  padding: calc(var(--u) * 3) calc(var(--u) * 1.5);
  border-top: var(--border);
  transition: background 0.18s var(--ease);
}

.page-about .about-band:last-child {
  border-bottom: var(--border);
}

.page-about .about-band:hover {
  background: rgba(13, 33, 54, 0.72);
}

.page-about .about-band-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  border: 1px solid var(--cyan);
  color: var(--cyan);
  font-family: var(--font-mono);
  font-size: var(--fs-small);
  line-height: 1;
}

.page-about .about-band-body h3 {
  margin: 0 0 calc(var(--u) * 1);
  font-size: var(--fs-h3);
  font-weight: 800;
  line-height: 1.3;
}

.page-about .about-band-body p {
  margin: 0;
  max-width: 64ch;
  font-size: var(--fs-body);
  line-height: 1.72;
  color: rgba(244, 247, 250, 0.8);
}

.page-about .about-band-meta {
  grid-column: 2 / 3;
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.1em;
  color: var(--orange);
}

.page-about .about-coverage {
  margin-bottom: calc(var(--u) * 4);
}

.page-about .about-coverage-title {
  margin: 0 0 calc(var(--u) * 1.5);
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.16em;
  color: var(--cool);
}

.page-about .about-chips {
  display: flex;
  flex-wrap: wrap;
  gap: calc(var(--u) * 1);
  margin: 0 0 calc(var(--u) * 2);
  padding: 0;
  list-style: none;
}

.page-about .about-chips li {
  padding: 6px 12px;
  border: 1px solid var(--line-blue);
  background: rgba(13, 33, 54, 0.6);
  font-family: var(--font-mono);
  font-size: var(--fs-small);
  color: var(--paper);
}

.page-about .about-coverage-note {
  margin: 0;
  max-width: 60ch;
  font-size: var(--fs-small);
  line-height: 1.7;
  color: var(--cool);
}

.page-about .about-side-note {
  margin: 0;
  padding-left: calc(var(--u) * 2.5);
  border-left: 3px solid var(--cyan);
  max-width: 66ch;
  font-size: var(--fs-small);
  line-height: 1.75;
  color: rgba(244, 247, 250, 0.74);
}

/* ---------- 03 时间线 ---------- */
.page-about .about-timeline-figure {
  position: relative;
  margin: 0 0 calc(var(--u) * 3);
  border: var(--border);
  background: var(--night-900);
  box-shadow: var(--shadow-hard-sm);
}

.page-about .about-timeline-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  filter: brightness(0.66) contrast(1.16) saturate(0.85);
}

.page-about .about-tl-axis {
  display: none;
  width: 100%;
  height: 40px;
  margin-bottom: calc(var(--u) * 1);
}

.page-about .about-timeline {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: calc(var(--u) * 2);
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-tl-node {
  position: relative;
  padding: calc(var(--u) * 3) calc(var(--u) * 2.5) calc(var(--u) * 2.5);
  border: var(--border);
  background: var(--night-700);
  transition: border-color 0.18s var(--ease), transform 0.18s var(--ease), box-shadow 0.18s var(--ease);
}

.page-about .about-tl-node:hover,
.page-about .about-tl-node:focus {
  border-color: var(--cyan);
  transform: translateY(-3px);
  box-shadow: var(--shadow-hard-sm);
}

.page-about .about-tl-dot {
  position: absolute;
  top: -8px;
  left: calc(var(--u) * 2.5);
  width: 12px;
  height: 12px;
  background: var(--orange);
  border: 2px solid var(--night-800);
}

.page-about .about-tl-phase {
  margin: 0 0 calc(var(--u) * 1);
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.14em;
  color: var(--cool);
}

.page-about .about-tl-node h3 {
  margin: 0 0 calc(var(--u) * 1);
  font-size: var(--fs-h3);
  font-weight: 800;
  line-height: 1.3;
}

.page-about .about-tl-summary {
  margin: 0;
  font-size: var(--fs-small);
  line-height: 1.7;
  color: rgba(244, 247, 250, 0.78);
}

.page-about .about-tl-note {
  margin: 0;
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  font-size: var(--fs-small);
  line-height: 1.7;
  color: var(--cyan);
  transition: max-height 0.25s var(--ease), opacity 0.2s var(--ease), margin 0.2s var(--ease);
}

.page-about .about-tl-node:hover .about-tl-note,
.page-about .about-tl-node:focus .about-tl-note,
.page-about .about-tl-node:focus-within .about-tl-note {
  max-height: 220px;
  opacity: 1;
  margin-top: calc(var(--u) * 1.5);
}

/* ---------- 04 团队 ---------- */
.page-about .about-team-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: calc(var(--u) * 3);
  margin-bottom: calc(var(--u) * 4);
}

.page-about .about-team-figure {
  margin: 0;
  border: var(--border);
  background: var(--night-900);
}

.page-about .about-team-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  filter: brightness(0.72) contrast(1.12) saturate(0.8);
}

.page-about .about-team-figure .about-figure-cap {
  margin: 0;
  padding: calc(var(--u) * 1.5) calc(var(--u) * 2);
  border-top: 1px solid var(--line-blue);
}

.page-about .about-team-nums {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line-blue);
  border: var(--border);
}

.page-about .about-num-cell {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: calc(var(--u) * 2.5);
  background: var(--night-800);
}

.page-about .about-num-cell--lead {
  grid-column: 1 / -1;
  background: var(--night-700);
}

.page-about .about-num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(34px, 7vw, 54px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--score);
}

.page-about .about-num--plain {
  font-size: clamp(26px, 5vw, 38px);
  color: var(--paper);
}

.page-about .about-num-label {
  font-size: var(--fs-small);
  line-height: 1.5;
  color: var(--cool);
}

.page-about .about-rhythm {
  padding-left: calc(var(--u) * 2.5);
  border-left: 3px solid var(--orange);
  max-width: 68ch;
}

.page-about .about-rhythm p {
  margin: 0;
  font-size: var(--fs-body);
  line-height: 1.78;
  color: rgba(244, 247, 250, 0.86);
}

/* ---------- 05 合作 ---------- */
.page-about .about-partners {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: calc(var(--u) * 2);
  margin-bottom: calc(var(--u) * 4);
}

.page-about .about-partner {
  padding: calc(var(--u) * 3) calc(var(--u) * 2.5);
  border-top: 3px solid var(--cyan);
  background: rgba(13, 33, 54, 0.62);
}

.page-about .about-partner-num {
  display: block;
  margin-bottom: calc(var(--u) * 1);
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(24px, 4vw, 32px);
  font-weight: 700;
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-partner h3 {
  margin: 0 0 calc(var(--u) * 1);
  font-size: var(--fs-h3);
  font-weight: 800;
  line-height: 1.3;
}

.page-about .about-partner p {
  margin: 0;
  font-size: var(--fs-small);
  line-height: 1.7;
  color: rgba(244, 247, 250, 0.78);
}

.page-about .about-partner-cta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: calc(var(--u) * 2);
  padding: calc(var(--u) * 3) calc(var(--u) * 2.5);
  border: var(--border);
  background: var(--night-700);
}

.page-about .about-partner-cta p {
  margin: 0;
  max-width: 56ch;
  font-size: var(--fs-body);
  line-height: 1.7;
  color: rgba(244, 247, 250, 0.86);
}

/* ---------- 06 为什么 ---------- */
.page-about .about-metrics {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0 0 calc(var(--u) * 4);
  padding: 0;
  list-style: none;
  background: var(--line-blue);
  border: var(--border);
}

.page-about .about-metric {
  padding: calc(var(--u) * 3) calc(var(--u) * 2.5);
  background: var(--night-800);
}

.page-about .about-metric-num {
  display: block;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(26px, 4.4vw, 40px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--cyan);
}

.page-about .about-metric-label {
  display: block;
  margin-top: calc(var(--u) * 1);
  font-size: var(--fs-small);
  line-height: 1.5;
  color: var(--cool);
}

.page-about .about-scenes {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: calc(var(--u) * 3);
}

.page-about .about-scene {
  padding-left: calc(var(--u) * 2.5);
  border-left: 2px solid var(--line-blue);
  transition: border-color 0.18s var(--ease);
}

.page-about .about-scene:hover {
  border-color: var(--orange);
}

.page-about .about-scene h3 {
  margin: 0 0 calc(var(--u) * 1);
  font-size: var(--fs-h3);
  font-weight: 800;
  line-height: 1.3;
}

.page-about .about-scene p {
  margin: 0;
  font-size: var(--fs-body);
  line-height: 1.72;
  color: rgba(244, 247, 250, 0.8);
}

.page-about .about-cta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: calc(var(--u) * 3);
  margin-top: calc(var(--u) * 5);
  padding: calc(var(--u) * 4) calc(var(--u) * 3);
  border: var(--border);
  background:
    linear-gradient(120deg, rgba(57, 245, 200, 0.12), transparent 46%),
    var(--night-700);
  box-shadow: var(--shadow-hard-sm);
}

.page-about .about-cta p {
  margin: 0;
  max-width: 46ch;
  font-size: var(--fs-body);
  line-height: 1.7;
  color: var(--paper);
}

.page-about .about-cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: calc(var(--u) * 1.5);
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-partners {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-scenes {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 820px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  }
  .page-about .about-band {
    grid-template-columns: 40px minmax(0, 1fr) 96px;
    align-items: center;
    padding-left: calc(var(--u) * 2.5);
  }
  .page-about .about-band:nth-child(2) {
    padding-right: 8%;
  }
  .page-about .about-band:nth-child(3) {
    padding-left: calc(var(--u) * 5);
  }
  .page-about .about-team-grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    align-items: start;
  }
  .page-about .about-tl-axis {
    display: block;
  }
  .page-about .about-timeline {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: calc(var(--u) * 2);
    align-items: start;
  }
  .page-about .about-tl-node:nth-child(2),
  .page-about .about-tl-node:nth-child(4) {
    margin-top: calc(var(--u) * 4);
  }
  .page-about .about-metrics {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding-top: calc(var(--u) * 6);
  }
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: calc(var(--u) * 6);
  }
}

@media (min-width: 1000px) {
  .page-about .about-layout {
    grid-template-columns: 200px minmax(0, 1fr);
    gap: calc(var(--u) * 7);
  }
  .page-about .about-index {
    position: sticky;
    top: 96px;
    align-self: start;
  }
  .page-about .about-index-list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding-bottom: 0;
    border-left: 2px solid var(--line-blue);
  }
  .page-about .about-index-link {
    padding: 10px 0 10px 12px;
    border: 0;
    border-left: 2px solid transparent;
    margin-left: -2px;
  }
  .page-about .about-index-link:hover {
    color: var(--paper);
    border-left-color: var(--cyan);
    background: rgba(13, 33, 54, 0.7);
  }
}

@media (hover: none) {
  .page-about .about-tl-note {
    max-height: none;
    opacity: 1;
    margin-top: calc(var(--u) * 1.5);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-tl-node,
  .page-about .about-tl-note,
  .page-about .about-index-link,
  .page-about .about-band {
    transition: none;
  }
  .page-about .about-tl-node:hover,
  .page-about .about-tl-node:focus {
    transform: none;
  }
}
<<<END>>>