.page-about {
  --ab-index-w: 232px;
  --ab-shell: var(--shell);
  --ab-cyan-soft: rgba(34, 224, 200, .12);
  display: block;
  padding-bottom: clamp(48px, 7vw, 96px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(120% 96% at 88% -14%, rgba(34, 224, 200, .16), transparent 62%),
    radial-gradient(90% 70% at 4% 110%, rgba(124, 107, 255, .12), transparent 68%),
    linear-gradient(180deg, var(--ink-800), var(--ink-900) 82%);
}

.page-about .about-hero__inner {
  padding-top: clamp(22px, 3.6vw, 40px);
  padding-bottom: clamp(26px, 4vw, 44px);
}

.page-about .about-hero .crumbs {
  margin-bottom: clamp(16px, 2.4vw, 26px);
}

.page-about .about-hero__title {
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(29px, 4.6vw, 48px);
  line-height: 1.15;
  letter-spacing: -0.02em;
  color: var(--paper);
  max-width: 22ch;
}

.page-about .about-hero__split {
  display: grid;
  gap: clamp(22px, 3vw, 36px);
  margin-top: clamp(20px, 3vw, 30px);
}

@media (min-width: 900px) {
  .page-about .about-hero__split {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
    align-items: start;
  }
}

.page-about .about-hero__lede {
  margin: 0;
  font-size: clamp(16px, 1.5vw, 18px);
  line-height: 1.85;
  color: var(--mist);
  max-width: 50ch;
}

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

.page-about .about-hero__facts li {
  background: var(--ink-900);
  padding: 12px 14px;
  display: flex;
  flex-direction: column;
  gap: 3px;
  min-width: 0;
}

.page-about .about-hero__facts .num {
  font-family: var(--font-mono);
  font-size: 20px;
  font-weight: 500;
  line-height: 1.1;
  color: var(--cyan-signal);
}

.page-about .about-hero__facts li > span:last-child {
  font-size: 12px;
  line-height: 1.5;
  color: var(--mist);
  letter-spacing: .02em;
}

.page-about .about-hero__figure {
  margin: 0;
  border-top: 1px solid var(--line);
  position: relative;
  overflow: hidden;
}

.page-about .about-hero__figure::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 42%;
  background: linear-gradient(180deg, transparent, rgba(6, 14, 28, .82));
  pointer-events: none;
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: clamp(200px, 30vw, 380px);
  object-fit: cover;
  filter: saturate(.86) contrast(1.06);
}

.page-about .about-hero__caption {
  position: relative;
  z-index: 1;
  display: block;
  max-width: var(--ab-shell);
  margin: 0 auto;
  padding: 12px var(--gutter) 0;
  font-size: 12px;
  line-height: 1.6;
  color: var(--mist);
}

/* ---------- 主体两栏 ---------- */
.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 44px);
  padding-top: clamp(26px, 4.5vw, 52px);
}

@media (min-width: 1000px) {
  .page-about .about-layout {
    grid-template-columns: var(--ab-index-w) minmax(0, 1fr);
    gap: clamp(36px, 5vw, 72px);
  }
}

/* ---------- 左侧索引 ---------- */
.page-about .about-index {
  align-self: start;
  border: 1px solid var(--line);
  background: var(--ink-800);
  padding: 16px 14px;
}

@media (min-width: 1000px) {
  .page-about .about-index {
    position: sticky;
    top: 104px;
  }
}

.page-about .about-index__label {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--mist);
  text-transform: uppercase;
}

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

@media (min-width: 1000px) {
  .page-about .about-index__list {
    grid-template-columns: minmax(0, 1fr);
  }
}

.page-about .about-index__list a {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 9px 10px;
  font-size: 14px;
  line-height: 1.4;
  color: var(--mist);
  text-decoration: none;
  border-left: 2px solid transparent;
  transition: color .2s ease, background-color .2s ease, border-color .2s ease;
}

.page-about .about-index__list a:hover,
.page-about .about-index__list a:focus-visible {
  color: var(--paper);
  background: var(--ink-700);
  border-left-color: var(--cyan-signal);
}

.page-about .about-index__list .num {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--cyan-signal);
}

.page-about .about-index__stats {
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px solid var(--line);
}

.page-about .about-index__stats-title {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--mist);
}

.page-about .about-index__stats-list {
  margin: 0;
  display: grid;
  gap: 8px;
}

@media (max-width: 999px) {
  .page-about .about-index__stats-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .about-index__stat {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 8px;
  min-width: 0;
}

@media (max-width: 999px) {
  .page-about .about-index__stat {
    flex-direction: column;
    gap: 2px;
  }
}

.page-about .about-index__stat dt {
  font-size: 12px;
  line-height: 1.5;
  color: var(--mist);
}

.page-about .about-index__stat dd {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 500;
  color: var(--cyan-signal);
}

/* ---------- 右栏区块 ---------- */
.page-about .about-flow {
  min-width: 0;
}

.page-about .about-block {
  border-top: 1px solid var(--line);
  padding: clamp(28px, 4vw, 52px) 0;
}

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

.page-about .about-block__head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 18px;
}

.page-about .about-block__no {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .08em;
  color: var(--cyan-signal);
  flex: none;
}

.page-about .about-block__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(21px, 2.8vw, 30px);
  line-height: 1.25;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .about-copy {
  display: grid;
  gap: 1em;
  max-width: 64ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--paper);
}

.page-about .about-copy p {
  margin: 0;
}

/* 受众三类 */
.page-about .about-audience {
  list-style: none;
  margin: clamp(20px, 3vw, 28px) 0 0;
  padding: 0;
  display: grid;
  gap: 20px;
}

@media (min-width: 760px) {
  .page-about .about-audience {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 22px;
  }
}

.page-about .about-audience li {
  display: grid;
  gap: 10px;
  align-content: start;
  padding-top: 14px;
  border-top: 2px solid var(--line-strong);
}

.page-about .about-audience .tag {
  justify-self: start;
}

.page-about .about-audience p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--mist);
}

/* 规模表 */
.page-about .about-table-wrap {
  margin-top: clamp(20px, 3vw, 28px);
  border: 1px solid var(--line);
  background: var(--ink-800);
  overflow-x: auto;
}

.page-about .about-table-wrap .ledger {
  width: 100%;
  min-width: 520px;
}

/* 团队三组 */
.page-about .about-teams {
  list-style: none;
  margin: clamp(20px, 3vw, 28px) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

@media (min-width: 760px) {
  .page-about .about-teams {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .about-teams__item {
  background: var(--ink-800);
  padding: 20px 18px;
  display: grid;
  gap: 10px;
  align-content: start;
  transition: background-color .2s ease;
}

.page-about .about-teams__item:hover {
  background: var(--ink-700);
}

.page-about .about-teams__tag {
  justify-self: start;
}

.page-about .about-teams__name {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .about-teams__item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--mist);
}

.page-about .about-feature {
  margin: clamp(22px, 3vw, 30px) 0 0;
  padding: 10px;
  border: 1px solid var(--line);
  background: var(--ink-800);
}

.page-about .about-feature img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-about .about-feature figcaption {
  margin-top: 10px;
  padding-top: 10px;
  border-top: 1px solid var(--line-soft);
  font-size: 12px;
  line-height: 1.65;
  color: var(--mist);
}

/* 时间轴 */
.page-about .about-strip {
  margin: 0 0 clamp(22px, 3vw, 30px);
  border: 1px solid var(--line);
  overflow: hidden;
}

.page-about .about-strip img {
  display: block;
  width: 100%;
  height: clamp(108px, 16vw, 180px);
  object-fit: cover;
  filter: saturate(.9);
}

.page-about .about-timeline {
  list-style: none;
  margin: 0;
  padding: 4px 0 0 28px;
  position: relative;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan-signal), rgba(34, 224, 200, .18) 70%, transparent);
}

.page-about .about-timeline__item {
  position: relative;
  padding-bottom: clamp(22px, 3vw, 30px);
}

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

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 7px;
  width: 8px;
  height: 8px;
  background: var(--ink-900);
  border: 1px solid var(--cyan-signal);
  transform: rotate(45deg);
}

.page-about .about-timeline__year {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 500;
  letter-spacing: .04em;
  color: var(--cyan-signal);
  padding: 1px 8px;
  border: 1px solid var(--line-strong);
  background: rgba(34, 224, 200, .07);
}

.page-about .about-timeline__name {
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 18px;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .about-timeline__text {
  margin: 8px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--mist);
  max-width: 58ch;
}

.page-about .about-timeline__more {
  margin: 10px 0 0;
  padding-left: 12px;
  border-left: 2px solid var(--violet-link);
  font-size: 13px;
  line-height: 1.7;
  color: var(--mist);
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  transition: max-height .28s ease, opacity .28s ease, margin-top .28s ease;
}

.page-about .about-timeline__item:hover .about-timeline__more,
.page-about .about-timeline__item:focus-within .about-timeline__more {
  max-height: 8em;
  opacity: 1;
}

@media (hover: none) {
  .page-about .about-timeline__more {
    max-height: none;
    opacity: 1;
  }
}

/* 延伸入口 */
.page-about .about-links {
  list-style: none;
  margin: clamp(20px, 3vw, 28px) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

@media (min-width: 760px) {
  .page-about .about-links {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.page-about .about-links a {
  display: grid;
  gap: 5px;
  padding: 16px 18px;
  height: 100%;
  background: var(--ink-800);
  border-left: 2px solid transparent;
  text-decoration: none;
  transition: background-color .2s ease, border-color .2s ease;
}

.page-about .about-links a:hover,
.page-about .about-links a:focus-visible {
  background: var(--ink-700);
  border-left-color: var(--cyan-signal);
}

.page-about .about-links__label {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 16px;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .about-links__desc {
  font-size: 13px;
  line-height: 1.7;
  color: var(--mist);
}

.page-about .about-pull {
  margin: clamp(22px, 3vw, 30px) 0 0;
  padding: 4px 0 4px 16px;
  border-left: 2px solid var(--orange-signal);
  font-family: var(--font-display);
  font-size: clamp(16px, 1.9vw, 19px);
  line-height: 1.65;
  color: var(--paper);
  max-width: 52ch;
}

.page-about .about-cta {
  margin: clamp(20px, 3vw, 26px) 0 0;
}

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

/* ---------- 动效降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .about-index__list a,
  .page-about .about-teams__item,
  .page-about .about-links a,
  .page-about .about-timeline__more {
    transition: none;
  }

  .page-about .about-timeline__more {
    max-height: none;
    opacity: 1;
  }
}
<<<END>>>