.page-about {
  --ab-index-w: 210px;
  --ab-gap: 56px;
  position: relative;
}

.page-about .breadcrumb__link {
  color: var(--muted);
  text-decoration: none;
  font-size: 13px;
  transition: color .2s var(--ease);
}

.page-about .breadcrumb__link:hover,
.page-about .breadcrumb__link:focus-visible {
  color: var(--cyan);
}

.page-about .breadcrumb__current {
  color: var(--text);
  font-size: 13px;
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  display: grid;
  gap: 36px;
  padding-block: 18px 64px;
}

.page-about .ab-hero__text .lede {
  margin-top: 18px;
  max-width: 46ch;
}

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

.page-about .ab-figures {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.page-about .ab-figures__item {
  padding: 16px 14px;
  background: var(--panel-deep);
}

.page-about .ab-figures__item:last-child {
  grid-column: 1 / -1;
}

.page-about .ab-figures dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--muted);
}

.page-about .ab-figures dd {
  margin: 8px 0 0;
  font-family: var(--font-display);
  font-size: 30px;
  font-weight: 800;
  line-height: 1;
  color: var(--cyan);
}

/* ---------- 双栏主体 ---------- */
.page-about .ab-body {
  display: grid;
  gap: 0;
  padding-bottom: 72px;
}

.page-about .ab-index {
  padding-bottom: 32px;
}

.page-about .ab-index__title {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--muted);
}

.page-about .ab-index__list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 4px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
}

.page-about .ab-index__list::-webkit-scrollbar {
  display: none;
}

.page-about .ab-index__link {
  display: block;
  padding: 8px 15px;
  border: 1px solid var(--line-soft);
  border-radius: var(--pill);
  background: var(--panel-deep);
  color: var(--muted);
  font-size: 13px;
  text-decoration: none;
  white-space: nowrap;
  transition: color .22s var(--ease), border-color .22s var(--ease), transform .22s var(--ease);
}

.page-about .ab-index__link:hover,
.page-about .ab-index__link:focus-visible {
  color: var(--cyan);
  border-color: var(--cyan);
  transform: translateY(-2px);
}

.page-about .ab-flow {
  display: grid;
  gap: 64px;
  min-width: 0;
}

.page-about .ab-flow > section {
  scroll-margin-top: calc(var(--header-space) + 24px);
}

.page-about .ab-sec__head {
  margin-bottom: 28px;
}

.page-about .ab-sec__head .prose {
  margin-top: 14px;
}

/* ---------- 缘起横带 ---------- */
.page-about .ab-band {
  position: relative;
  padding: 34px 22px 38px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-xl);
  background: linear-gradient(152deg, var(--panel-deep) 0%, var(--ink-deep) 100%);
  overflow: hidden;
}

.page-about .ab-band::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(112deg, transparent 41%, rgba(53, 240, 208, .14) 50%, transparent 59%),
    radial-gradient(560px 220px at 92% -10%, rgba(255, 61, 154, .2), transparent 70%);
  pointer-events: none;
}

.page-about .ab-band > * {
  position: relative;
}

.page-about .ab-band__cols {
  display: grid;
  gap: 16px;
  margin-top: 18px;
}

.page-about .ab-band__cols p {
  margin: 0;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.75;
}

/* ---------- 分类体系 ---------- */
.page-about .ab-tax__grid {
  display: grid;
  gap: 24px;
}

.page-about .ab-tax__figure {
  margin: 0;
  padding: 14px;
  border-radius: var(--radius-lg);
  background:
    radial-gradient(circle at 50% 42%, rgba(53, 240, 208, .13), transparent 64%),
    var(--panel-deep);
}

.page-about .ab-tax__figure img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: var(--radius-md);
  object-fit: cover;
}

.page-about .ab-tax__figure figcaption {
  margin-top: 12px;
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--muted);
}

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

.page-about .ab-specs__item {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 13px 16px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-md);
  background: var(--panel-deep);
  transition: border-color .24s var(--ease), transform .24s var(--ease);
}

.page-about .ab-specs__item:hover {
  border-color: var(--cyan);
  transform: translateY(-3px);
}

.page-about .ab-specs__num {
  flex: none;
  min-width: 2.4ch;
  font-family: var(--font-display);
  font-size: 26px;
  font-weight: 800;
  line-height: 1;
  color: var(--amber);
}

.page-about .ab-specs__label {
  font-size: 14px;
  line-height: 1.55;
  color: var(--muted);
}

.page-about .ab-tax__note {
  margin-top: 16px;
}

/* ---------- 版本演进 ---------- */
.page-about .ab-vers__beam {
  margin: 0 0 26px;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: linear-gradient(120deg, var(--panel-deep), var(--ink-deep));
}

.page-about .ab-vers__beam img {
  display: block;
  width: 100%;
  height: 168px;
  object-fit: cover;
}

.page-about .ab-vers__track {
  display: none;
}

.page-about .ab-vers__list {
  display: grid;
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-vers__item {
  padding: 22px 20px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-lg);
  background: var(--panel-deep);
  transition: transform .24s var(--ease), border-color .24s var(--ease), box-shadow .24s var(--ease);
}

.page-about .ab-vers__item:hover,
.page-about .ab-vers__item:focus-within {
  transform: translateY(-4px);
  border-color: var(--cyan);
  box-shadow: var(--glow-cyan);
}

.page-about .ab-vers__item .h-sub {
  margin: 12px 0 8px;
}

.page-about .ab-vers__item p:last-child {
  margin: 0;
  color: var(--muted);
  font-size: 14.5px;
  line-height: 1.75;
}

.page-about .ab-vers__foot {
  margin-top: 24px;
  padding-left: 16px;
  border-left: 2px solid var(--magenta);
  color: var(--muted);
}

/* ---------- 团队 ---------- */
.page-about .ab-team__grid {
  display: grid;
  gap: 28px;
  align-items: start;
}

.page-about .ab-team__text .prose {
  margin-top: 14px;
}

.page-about .ab-steps {
  display: grid;
  gap: 14px;
  margin: 22px 0 24px;
  padding: 0;
  list-style: none;
  counter-reset: abstep;
}

.page-about .ab-steps__item {
  position: relative;
  padding-left: 44px;
  color: var(--muted);
  font-size: 14.5px;
  line-height: 1.72;
}

.page-about .ab-steps__item::before {
  counter-increment: abstep;
  content: counter(abstep, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 0;
  padding: 2px 8px;
  border: 1px solid var(--line-soft);
  border-radius: var(--pill);
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--cyan);
}

.page-about .ab-team__media {
  margin: 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background:
    linear-gradient(135deg, rgba(255, 61, 154, .18), rgba(53, 240, 208, .14)),
    var(--panel-deep);
}

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

/* ---------- 协作网络 ---------- */
.page-about .ab-net__grid {
  display: grid;
  gap: 16px;
}

.page-about .ab-net__card {
  padding: 24px 20px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-lg);
  background: linear-gradient(160deg, var(--panel), var(--panel-deep));
  transition: border-color .24s var(--ease), transform .24s var(--ease);
}

.page-about .ab-net__card:hover {
  border-color: var(--cyan-soft);
  transform: translateY(-4px);
}

.page-about .ab-net__num {
  margin: 0;
  font-family: var(--font-display);
  font-size: 44px;
  font-weight: 900;
  line-height: 1;
  color: var(--cyan);
}

.page-about .ab-net__card .h-sub {
  margin: 10px 0 10px;
}

.page-about .ab-net__card p:last-child {
  margin: 0;
  color: var(--muted);
  font-size: 14.5px;
  line-height: 1.75;
}

.page-about .ab-net__foot {
  margin-top: 22px;
}

.page-about .ab-net__foot + .btn {
  margin-top: 20px;
}

/* ---------- 斜切分隔 ---------- */
.page-about .ab-slant {
  height: 44px;
  background: linear-gradient(90deg, transparent, rgba(53, 240, 208, .3), rgba(255, 61, 154, .22), transparent);
  clip-path: polygon(0 64%, 100% 0, 100% 36%, 0 100%);
}

/* ---------- 承诺 ---------- */
.page-about .ab-promise__list {
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line-soft);
}

.page-about .ab-promise__item {
  display: grid;
  gap: 8px;
  padding: 26px 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .ab-promise__idx {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--amber);
}

.page-about .ab-promise__item .h-sub {
  margin: 0;
}

.page-about .ab-promise__item p {
  margin: 0;
  color: var(--muted);
  font-size: 14.5px;
  line-height: 1.75;
}

.page-about .ab-cta {
  margin-top: 34px;
  padding: 26px 22px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-xl);
  background:
    radial-gradient(520px 200px at 88% 0%, rgba(255, 178, 91, .16), transparent 70%),
    linear-gradient(140deg, var(--panel-deep), var(--ink-deep));
}

.page-about .ab-cta__text {
  margin: 0 0 18px;
  max-width: 40ch;
  color: var(--text);
  font-size: 16px;
  line-height: 1.7;
}

.page-about .ab-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 560px) {
  .page-about .ab-band {
    padding: 40px 32px 44px;
  }

  .page-about .ab-vers__beam img {
    height: 200px;
  }
}

@media (min-width: 760px) {
  .page-about .ab-figures {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }

  .page-about .ab-figures__item:last-child {
    grid-column: auto;
  }

  .page-about .ab-band__cols {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 22px;
  }

  .page-about .ab-net__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 22px;
  }
}

@media (min-width: 900px) {
  .page-about .ab-hero {
    grid-template-columns: minmax(0, 1fr) 300px;
    gap: 56px;
    align-items: end;
    padding-block: 28px 88px;
  }

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

  .page-about .ab-figures__item:last-child {
    grid-column: 1 / -1;
  }

  .page-about .ab-tax__grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
    gap: 40px;
    align-items: center;
  }

  .page-about .ab-vers__track {
    display: block;
    height: 2px;
    margin-bottom: 22px;
    border-radius: var(--pill);
    background: linear-gradient(90deg, var(--magenta), var(--cyan) 62%, var(--amber));
  }

  .page-about .ab-vers__list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 20px;
  }

  .page-about .ab-team__grid {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, .88fr);
    gap: 44px;
  }

  .page-about .ab-promise__item {
    grid-template-columns: 60px minmax(0, 230px) minmax(0, 1fr);
    gap: 22px;
    align-items: baseline;
  }
}

@media (min-width: 1024px) {
  .page-about .ab-body {
    grid-template-columns: var(--ab-index-w) minmax(0, 1fr);
    gap: var(--ab-gap);
    align-items: start;
  }

  .page-about .ab-index {
    position: sticky;
    top: calc(var(--header-space) + 28px);
    padding-bottom: 0;
    padding-top: 6px;
  }

  .page-about .ab-index__list {
    flex-direction: column;
    gap: 2px;
    overflow: visible;
  }

  .page-about .ab-index__link {
    border-color: transparent;
    background: transparent;
    padding-left: 12px;
  }

  .page-about .ab-index__link:hover,
  .page-about .ab-index__link:focus-visible {
    background: var(--panel-deep);
    border-color: var(--cyan);
    transform: translateX(3px);
  }

  .page-about .ab-flow {
    gap: 78px;
  }

  .page-about .ab-band {
    padding: 48px 46px 52px;
  }

  .page-about .ab-vers__beam img {
    height: 232px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-index__link,
  .page-about .ab-specs__item,
  .page-about .ab-vers__item,
  .page-about .ab-net__card {
    transition: opacity .2s linear;
  }

  .page-about .ab-index__link:hover,
  .page-about .ab-index__link:focus-visible,
  .page-about .ab-specs__item:hover,
  .page-about .ab-vers__item:hover,
  .page-about .ab-net__card:hover {
    transform: none;
  }
}
<<<END>>>