.page-about {
  background: var(--bg);
  color: var(--c-ink);
  font-family: var(--font-body);
  line-height: 1.75;
  overflow-x: hidden;
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  padding: 40px 0 56px;
  border-bottom: 1px solid var(--line);
  background:
    linear-gradient(180deg, rgba(0, 232, 206, 0.05) 0%, rgba(5, 7, 10, 0) 42%),
    var(--bg);
}

.page-about .ab-hero__grid {
  display: grid;
  gap: 28px;
}

.page-about .ab-tally {
  border-left: 1px solid var(--line);
  padding-left: 16px;
}

.page-about .ab-tally__cap {
  margin: 0 0 12px;
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--c-muted);
}

.page-about .ab-tally__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-tally__row {
  display: flex;
  align-items: baseline;
  gap: 8px;
}

.page-about .ab-tally__y {
  font-size: 14px;
  color: var(--c-cyan);
  letter-spacing: 0.04em;
}

.page-about .ab-tally__n {
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--c-muted);
}

.page-about .ab-crumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--c-muted);
  margin-bottom: 26px;
}

.page-about .ab-crumb__link {
  color: var(--c-muted);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--dur) ease, border-color var(--dur) ease;
}

.page-about .ab-crumb__link:hover {
  color: var(--c-cyan);
  border-bottom-color: var(--c-cyan);
}

.page-about .ab-crumb__sep {
  color: var(--c-line);
}

.page-about .ab-crumb__cur {
  color: var(--c-ink);
}

.page-about .ab-hero__title {
  margin: 0 0 24px;
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(32px, 7vw, 68px);
  line-height: 1.08;
  letter-spacing: -0.02em;
  color: var(--c-white);
  max-width: 22ch;
}

.page-about .ab-hero__lead {
  max-width: var(--w-text);
  margin: 0 0 8px;
  color: var(--c-ink);
}

.page-about .ab-hero__stats {
  display: grid;
  gap: 1px;
  margin-top: 38px;
  background-color: var(--line);
  border: 1px solid var(--line);
}

.page-about .ab-stat {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 18px 20px 22px;
  background: var(--c-panel);
}

.page-about .ab-stat--lg {
  background: var(--c-raise);
}

.page-about .ab-stat__value {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(30px, 7vw, 46px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--c-white);
}

.page-about .ab-stat--lg .ab-stat__value {
  font-size: clamp(42px, 9vw, 64px);
  color: var(--c-cyan);
  text-shadow: 0 0 24px var(--accent-soft);
}

.page-about .ab-stat__unit {
  margin-left: 4px;
  font-size: 15px;
  color: var(--c-muted);
}

.page-about .ab-stat__label {
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--c-muted);
}

/* ---------- 章节通用 ---------- */
.page-about .ab-section {
  padding: 60px 0;
  border-top: 1px solid var(--line);
}

.page-about .ab-section:first-of-type {
  border-top: 0;
}

.page-about .ab-section__head {
  margin-bottom: 36px;
}

.page-about .ab-section__lead {
  margin: 14px 0 0;
  max-width: 56ch;
  font-size: 15px;
  color: var(--c-muted);
}

.page-about .ab-h2 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 400;
  font-size: clamp(24px, 4.4vw, 40px);
  line-height: 1.18;
  letter-spacing: -0.01em;
  color: var(--c-white);
  max-width: 26ch;
}

.page-about .ab-p {
  margin: 0 0 18px;
  max-width: 68ch;
  color: var(--c-ink);
}

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

/* 双栏：窄注释 + 宽正文 */
.page-about .ab-cols {
  display: grid;
  gap: 28px;
}

.page-about .ab-cols__aside {
  border-left: 1px solid var(--line);
  padding-left: 16px;
}

.page-about .ab-cols__aside .note {
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--c-muted);
  max-width: 34ch;
}

/* ---------- 图片 ---------- */
.page-about .ab-figure {
  margin: 0;
  border: 1px solid var(--line);
  background: var(--c-panel);
}

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

.page-about .ab-figure figcaption {
  padding: 10px 14px;
  border-top: 1px solid var(--line);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--c-muted);
}

.page-about .ab-figure--band {
  margin-bottom: 36px;
}

/* ---------- 时间轴手风琴 ---------- */
.page-about .ab-timeline {
  border-top: 1px solid var(--line);
}

.page-about .ab-timeline .accordion__item {
  border-bottom: 1px solid var(--line);
  transition: background-color var(--dur) ease;
}

.page-about .ab-timeline .accordion__item[data-read="true"] {
  background: rgba(0, 232, 206, 0.03);
}

.page-about .ab-timeline .accordion__trigger {
  display: grid;
  grid-template-columns: 62px 1fr 24px;
  align-items: center;
  gap: 14px;
  width: 100%;
  padding: 20px 4px;
  border: 0;
  background: transparent;
  color: inherit;
  font: inherit;
  text-align: left;
  cursor: pointer;
}

.page-about .ab-timeline__year {
  font-size: 15px;
  letter-spacing: 0.04em;
  color: var(--c-cyan);
}

.page-about .ab-timeline__title {
  font-size: 16px;
  line-height: 1.5;
  color: var(--c-ink);
  transition: color var(--dur) ease;
}

.page-about .ab-timeline .accordion__trigger:hover .ab-timeline__title,
.page-about .ab-timeline .accordion__trigger[aria-expanded="true"] .ab-timeline__title {
  color: var(--c-white);
}

.page-about .ab-timeline__mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 22px;
  height: 22px;
  border: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1;
  color: var(--c-muted);
  transition: transform var(--dur) ease, color var(--dur) ease, border-color var(--dur) ease;
}

.page-about .ab-timeline .accordion__trigger[aria-expanded="true"] .ab-timeline__mark {
  color: var(--c-cyan);
  border-color: var(--c-cyan-dim);
  transform: rotate(90deg);
}

.page-about .ab-timeline .accordion__panel {
  padding: 0 4px 22px 80px;
  overflow: hidden;
}

.page-about .ab-timeline .accordion__panel[hidden] {
  display: none;
}

.page-about .ab-timeline .accordion__panel .ab-p {
  font-size: 15px;
  color: var(--c-ink);
}

/* ---------- 能力带（页签） ---------- */
.page-about .ab-belts {
  border: 1px solid var(--line);
  background: var(--c-panel);
}

.page-about .ab-belts__bar {
  display: flex;
  flex-wrap: wrap;
  gap: 0;
  border-bottom: 1px solid var(--line);
  background: var(--c-raise);
}

.page-about .ab-belts__tab {
  flex: 1 1 auto;
  min-width: 108px;
  padding: 14px 12px;
  border: 0;
  border-right: 1px solid var(--line);
  background: transparent;
  color: var(--c-muted);
  font-family: var(--font-body);
  font-size: 13px;
  letter-spacing: 0.12em;
  cursor: pointer;
  transition: color var(--dur) ease, background-color var(--dur) ease;
}

.page-about .ab-belts__tab:last-child {
  border-right: 0;
}

.page-about .ab-belts__tab[aria-selected="true"] {
  color: var(--c-cyan);
  background: var(--accent-soft);
  box-shadow: inset 0 -1px 0 var(--c-cyan);
}

.page-about .ab-belts__tab:hover {
  color: var(--c-white);
}

.page-about .ab-belt {
  display: grid;
  gap: 1px;
  background: var(--line);
  padding: 0;
}

.page-about .ab-belt[hidden] {
  display: none;
}

.page-about .ab-belt__row {
  display: grid;
  gap: 6px;
  padding: 18px 20px;
  background: var(--c-panel);
}

.page-about .ab-belt__k {
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--c-cyan);
}

.page-about .ab-belt__v {
  font-size: 15px;
  color: var(--c-ink);
}

.page-about .ab-belt__v .num {
  color: var(--c-white);
  font-size: 18px;
}

/* ---------- 值守（左文右图） ---------- */
.page-about .ab-split {
  display: grid;
  gap: 32px;
}

.page-about .ab-split__text .ab-h2 {
  margin-bottom: 22px;
}

.page-about .ab-split__media img {
  aspect-ratio: 14 / 9;
}

/* ---------- 覆盖面 ---------- */
.page-about .ab-coverage {
  display: grid;
  gap: 32px;
}

.page-about .ab-coverage__media img {
  aspect-ratio: 3 / 2;
}

.page-about .ab-fields {
  list-style: none;
  margin: 0 0 24px;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .ab-fields__item {
  display: grid;
  gap: 4px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .ab-fields__name {
  font-size: 15px;
  color: var(--c-white);
  letter-spacing: 0.02em;
}

.page-about .ab-fields__desc {
  font-size: 13px;
  color: var(--c-muted);
}

.page-about .ab-callout {
  padding: 20px 22px;
  border: 1px solid var(--c-cyan-dim);
  background: linear-gradient(135deg, rgba(0, 232, 206, 0.09) 0%, rgba(0, 232, 206, 0) 70%);
}

.page-about .ab-callout__text {
  margin: 0;
  font-size: 15px;
  color: var(--c-ink);
}

/* ---------- 版本沿革 ---------- */
.page-about .ab-versions {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
}

.page-about .ab-versions__item {
  position: relative;
  padding: 0 0 24px 22px;
  border-left: 1px solid var(--line);
}

.page-about .ab-versions__item::before {
  content: "";
  position: absolute;
  left: -4px;
  top: 8px;
  width: 7px;
  height: 7px;
  background: var(--c-line);
}

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

.page-about .ab-versions__item.is-current::before {
  background: var(--c-cyan);
  box-shadow: 0 0 10px var(--accent-glow);
}

.page-about .ab-versions__tag {
  display: block;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--c-muted);
  margin-bottom: 8px;
}

.page-about .ab-versions__item.is-current .ab-versions__tag {
  color: var(--c-cyan);
}

.page-about .ab-versions__name {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-weight: 400;
  font-size: 19px;
  line-height: 1.35;
  color: var(--c-white);
}

.page-about .ab-versions__desc {
  margin: 0;
  font-size: 14px;
  color: var(--c-ink);
  max-width: 56ch;
}

/* ---------- 外部印证 ---------- */
.page-about .ab-partners {
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .ab-partner {
  display: grid;
  gap: 10px;
  padding: 24px 22px;
  background: var(--c-panel);
}

.page-about .ab-partner__num {
  font-size: clamp(28px, 6vw, 40px);
  line-height: 1;
  color: var(--c-amber);
  letter-spacing: -0.02em;
}

.page-about .ab-partner__text {
  margin: 0;
  font-size: 14px;
  color: var(--c-ink);
}

/* ---------- 收束 ---------- */
.page-about .ab-start {
  background:
    radial-gradient(120% 100% at 0% 0%, rgba(0, 232, 206, 0.08) 0%, rgba(5, 7, 10, 0) 60%),
    var(--c-panel);
}

.page-about .ab-start__title {
  max-width: 30ch;
}

.page-about .ab-start__text {
  margin-top: 18px;
  max-width: 62ch;
  color: var(--c-ink);
}

.page-about .ab-start__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.page-about .ab-start__actions .btn {
  text-decoration: none;
}

/* ---------- 右侧锚点索引 ---------- */
.page-about .ab-anchor {
  display: none;
}

.page-about .anchor-index__link {
  display: block;
  position: relative;
  padding: 6px 0 6px 14px;
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--c-muted);
  text-decoration: none;
  transition: color var(--dur) ease;
}

.page-about .anchor-index__link::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  width: 4px;
  height: 1px;
  background: var(--line);
  transform: translateY(-50%);
  transition: width var(--dur) ease, background-color var(--dur) ease;
}

.page-about .anchor-index__link:hover,
.page-about .anchor-index__link[aria-current="true"] {
  color: var(--c-cyan);
}

.page-about .anchor-index__link[aria-current="true"]::before {
  width: 10px;
  background: var(--c-cyan);
  box-shadow: 0 0 8px var(--accent-glow);
}

/* ---------- 响应式 ---------- */
@media (min-width: 700px) {
  .page-about .ab-hero__stats {
    grid-template-columns: 1.6fr 1fr 1fr;
  }

  .page-about .ab-belt__row {
    grid-template-columns: 132px 1fr;
    align-items: baseline;
    gap: 18px;
    padding: 20px 24px;
  }

  .page-about .ab-fields__item {
    grid-template-columns: 180px 1fr;
    align-items: baseline;
    gap: 18px;
  }

  .page-about .ab-partners {
    grid-template-columns: 1fr 1fr;
  }

  .page-about .ab-partner:first-child {
    grid-column: 1 / -1;
  }
}

@media (min-width: 900px) {
  .page-about .ab-hero {
    padding: 64px 0 72px;
  }

  .page-about .ab-hero__grid {
    grid-template-columns: 168px minmax(0, 1fr);
    gap: 52px;
  }

  .page-about .ab-tally {
    padding-left: 20px;
  }

  .page-about .ab-tally__list {
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 0;
  }

  .page-about .ab-tally__row {
    position: relative;
    display: block;
    padding: 14px 0;
    border-bottom: 1px solid var(--line);
  }

  .page-about .ab-tally__row::before {
    content: "";
    position: absolute;
    left: -24px;
    top: 22px;
    width: 8px;
    height: 1px;
    background: var(--c-cyan-dim);
  }

  .page-about .ab-tally__row.is-now::before {
    background: var(--c-cyan);
    box-shadow: 0 0 8px var(--accent-glow);
  }

  .page-about .ab-tally__y {
    display: block;
    font-size: 18px;
    line-height: 1.2;
  }

  .page-about .ab-tally__n {
    display: block;
    margin-top: 2px;
  }

  .page-about .ab-section {
    padding: 92px 0;
  }

  .page-about .ab-cols {
    grid-template-columns: 220px minmax(0, 1fr);
    gap: 56px;
  }

  .page-about .ab-cols--flip {
    grid-template-columns: 240px minmax(0, 1fr);
  }

  .page-about .ab-split {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
    gap: 48px;
    align-items: start;
  }

  .page-about .ab-coverage {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: 48px;
    align-items: start;
  }

  .page-about .ab-timeline .accordion__panel {
    padding-left: 96px;
    padding-right: 40px;
  }

  .page-about .ab-partners {
    grid-template-columns: 1.1fr 1fr 1fr;
  }

  .page-about .ab-partner:first-child {
    grid-column: auto;
  }
}

@media (min-width: 1180px) {
  .page-about .ab-anchor {
    display: flex;
    flex-direction: column;
    position: fixed;
    right: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 122px;
    padding: 18px 16px 18px 22px;
    background: linear-gradient(90deg, rgba(5, 7, 10, 0) 0%, rgba(5, 7, 10, 0.94) 26%, rgba(5, 7, 10, 0.99) 100%);
    z-index: 6;
  }
}

@media (min-width: 1440px) {
  .page-about .ab-timeline .accordion__trigger {
    grid-template-columns: 84px 1fr 24px;
  }

  .page-about .ab-timeline .accordion__panel {
    padding-left: 116px;
  }
}
<<<END>>>