.page-about {
  background: var(--c-ink);
  color: var(--c-paper);
  --ab-y: clamp(3rem, 7vw, 5.5rem);
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(1.6rem, 4vw, 2.6rem) 0 clamp(2.6rem, 6vw, 5rem);
  border-bottom: 1px solid var(--c-line);
}
.page-about .ab-hero::after {
  content: "";
  position: absolute;
  right: -18%;
  bottom: -55%;
  width: 78%;
  height: 105%;
  background: radial-gradient(closest-side, rgba(53, 242, 192, 0.13), transparent 72%);
  pointer-events: none;
}
.page-about .ab-hero__inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1.8rem, 5vw, 3rem);
  align-items: end;
}
.page-about .ab-crumb {
  margin-bottom: clamp(1rem, 3vw, 1.6rem);
}
.page-about .ab-hero__eyebrow {
  color: var(--c-amber);
  letter-spacing: 0.16em;
}
.page-about .ab-hero__title {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(2.4rem, 8vw, 5rem);
  line-height: 1.02;
  letter-spacing: -0.035em;
  margin: 0.55rem 0 0;
  color: var(--c-paper);
}
.page-about .ab-hero__title span {
  box-shadow: inset 0 -0.14em 0 rgba(255, 181, 71, 0.85);
}
.page-about .ab-hero__lead {
  margin: clamp(1.1rem, 3vw, 1.6rem) 0 0;
  max-width: 46ch;
  font-size: clamp(0.98rem, 1.5vw, 1.15rem);
  line-height: 1.85;
  color: var(--c-text-soft);
}
.page-about .ab-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(1.6rem, 4vw, 2.4rem) 0 0;
  background: var(--c-line);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  overflow: hidden;
}
.page-about .ab-hero__stat {
  background: var(--c-ink-2);
  padding: 0.85rem 0.95rem;
}
.page-about .ab-hero__stat dt {
  font-size: 0.74rem;
  letter-spacing: 0.08em;
  color: var(--c-mist);
}
.page-about .ab-hero__stat dd {
  margin: 0.35rem 0 0;
  font-family: var(--font-num);
  font-size: 0.95rem;
  color: var(--c-paper);
}
.page-about .ab-hero__stat dd .yb-num {
  font-size: 1.3rem;
  color: var(--c-mint);
  margin-right: 0.15rem;
}
.page-about .ab-hero__figure {
  margin: 0;
  position: relative;
  border: 1px solid var(--c-line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--c-ink-2);
}
.page-about .ab-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 5 / 6;
  object-fit: cover;
}
.page-about .ab-hero__cap {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 2.4rem 1rem 0.9rem;
  font-size: 0.78rem;
  letter-spacing: 0.06em;
  color: var(--c-paper);
  background: linear-gradient(to top, rgba(7, 17, 31, 0.92), transparent);
}

/* ---------- 章节目录 ---------- */
.page-about .ab-index {
  position: sticky;
  top: var(--yb-header-h);
  z-index: 5;
  background: rgba(7, 17, 31, 0.9);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--c-line);
}
.page-about .ab-index__inner {
  display: flex;
  align-items: center;
  gap: 1rem;
}
.page-about .ab-index__label {
  flex: none;
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  color: var(--c-mist);
  padding: 0.95rem 0;
}
.page-about .ab-index__list {
  display: flex;
  gap: clamp(0.9rem, 2.6vw, 1.9rem);
  margin: 0;
  padding: 0.95rem 0;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
}
.page-about .ab-index__list::-webkit-scrollbar {
  display: none;
}
.page-about .ab-index__link {
  display: inline-flex;
  align-items: baseline;
  gap: 0.4rem;
  white-space: nowrap;
  font-size: 0.84rem;
  color: var(--c-text-soft);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--t) var(--ease), border-color var(--t) var(--ease);
}
.page-about .ab-index__link .yb-num {
  color: var(--c-amber);
  font-size: 0.72rem;
}
.page-about .ab-index__link:hover,
.page-about .ab-index__link:focus-visible {
  color: var(--c-paper);
  border-bottom-color: var(--c-mint);
}

/* ---------- 通用章节 ---------- */
.page-about .ab-chapter {
  padding: var(--ab-y) 0;
  scroll-margin-top: calc(var(--yb-header-h) + 62px);
}
.page-about .ab-chapter__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1.4rem, 4vw, 3rem);
}
.page-about .ab-chapter__aside {
  display: flex;
  align-items: baseline;
  gap: 0.7rem;
}
.page-about .ab-chapter__num {
  font-size: clamp(1.5rem, 3vw, 2.1rem);
  color: var(--c-amber);
  letter-spacing: -0.02em;
}
.page-about .ab-chapter__label {
  font-size: 0.78rem;
  letter-spacing: 0.2em;
  color: var(--c-mist);
}
.page-about .ab-chapter__title {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(1.55rem, 4vw, 2.6rem);
  line-height: 1.18;
  letter-spacing: -0.02em;
  margin: 0 0 clamp(1rem, 2.5vw, 1.6rem);
  color: var(--c-paper);
  max-width: 22ch;
}
.page-about .ab-prose {
  max-width: 62ch;
}
.page-about .ab-lead {
  margin: 0 0 1.1rem;
  font-size: clamp(1rem, 1.7vw, 1.16rem);
  line-height: 1.85;
  color: var(--c-paper);
}
.page-about .ab-body {
  margin: 0 0 1.1rem;
  font-size: 0.97rem;
  line-height: 1.85;
  color: var(--c-text-soft);
}
.page-about .ab-body--wide {
  max-width: 60ch;
}
.page-about .ab-pull {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.6rem;
  margin: 1.6rem 0 0;
  padding: 1rem 0 0;
  list-style: none;
  border-top: 1px solid var(--c-line);
}
.page-about .ab-pull li {
  display: inline-flex;
  align-items: baseline;
  gap: 0.35rem;
  font-size: 0.86rem;
  color: var(--c-mist);
}
.page-about .ab-pull .yb-num {
  font-size: 1.25rem;
  color: var(--c-mint);
}

/* ---------- 纸面章节 ---------- */
.page-about .ab-chapter--paper {
  background: var(--c-paper);
  color: var(--c-ink);
  border-top: 1px solid var(--c-line);
  border-bottom: 1px solid var(--c-line);
}
.page-about .ab-paper__head {
  max-width: 64ch;
}
.page-about .ab-paper__num {
  display: block;
  font-size: 1.5rem;
  color: #b9761b;
  margin-bottom: 0.4rem;
}
.page-about .ab-paper__title {
  color: var(--c-ink);
  max-width: 20ch;
}
.page-about .ab-paper__intro {
  margin: 0;
  font-size: 0.99rem;
  line-height: 1.85;
  color: #3f5069;
}
.page-about .ab-cells {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(1.6rem, 4vw, 2.4rem) 0 0;
  padding: 1px;
  list-style: none;
  background: rgba(27, 43, 68, 0.2);
  border-radius: var(--radius);
  overflow: hidden;
}
.page-about .ab-cell {
  display: flex;
  align-items: baseline;
  gap: 0.55rem;
  padding: 1rem 0.85rem;
  background: var(--c-paper);
  transition: background var(--t) var(--ease), color var(--t) var(--ease);
}
.page-about .ab-cell__idx {
  font-size: 0.72rem;
  color: #b9761b;
  transition: color var(--t) var(--ease);
}
.page-about .ab-cell__name {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 1.05rem;
  letter-spacing: -0.01em;
  color: var(--c-ink);
  transition: color var(--t) var(--ease);
}
.page-about .ab-cell:hover {
  background: var(--c-ink);
}
.page-about .ab-cell:hover .ab-cell__name {
  color: var(--c-paper);
}
.page-about .ab-cell:hover .ab-cell__idx {
  color: var(--c-mint);
}
.page-about .ab-paper__foot {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1.4rem, 4vw, 2.4rem);
  margin-top: clamp(1.6rem, 4vw, 2.4rem);
  align-items: start;
}
.page-about .ab-paper__body {
  margin: 0;
  font-size: 0.97rem;
  line-height: 1.85;
  color: #3f5069;
  max-width: 46ch;
}
.page-about .ab-paper__figure {
  margin: 0;
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--c-deep-teal);
}
.page-about .ab-paper__figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}
.page-about .ab-figcap {
  display: block;
  padding: 0.7rem 0.9rem;
  font-size: 0.76rem;
  letter-spacing: 0.06em;
  color: var(--c-paper);
  background: var(--c-deep-teal);
}

/* ---------- 版本时间轴 ---------- */
.page-about .ab-timeline {
  list-style: none;
  margin: clamp(1.6rem, 4vw, 2.4rem) 0 0;
  padding: 0 0 0 1.7rem;
  border-left: 1px solid var(--c-line);
  display: grid;
  gap: clamp(1.5rem, 3.5vw, 2.2rem);
}
.page-about .ab-timeline__item {
  position: relative;
}
.page-about .ab-timeline__item::before {
  content: "";
  position: absolute;
  left: calc(-1.7rem - 5px);
  top: 0.45rem;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--c-ink);
  border: 1px solid var(--c-mint);
  transition: background var(--t) var(--ease), box-shadow var(--t) var(--ease);
}
.page-about .ab-timeline__item:hover::before {
  background: var(--c-mint);
  box-shadow: 0 0 0 5px rgba(53, 242, 192, 0.16);
}
.page-about .ab-timeline__item--accent::before {
  border-color: var(--c-amber);
}
.page-about .ab-timeline__item--accent:hover::before {
  background: var(--c-amber);
  box-shadow: 0 0 0 5px rgba(255, 181, 71, 0.16);
}
.page-about .ab-timeline__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.4rem 0.8rem;
}
.page-about .ab-timeline__phase {
  font-size: 0.74rem;
  letter-spacing: 0.16em;
  color: var(--c-mist);
}
.page-about .ab-timeline__tag {
  font-size: 0.74rem;
  padding: 0.14rem 0.5rem;
  border: 1px solid var(--c-line);
  border-radius: 999px;
  color: var(--c-mint);
}
.page-about .ab-timeline__item--accent .ab-timeline__tag {
  border-color: rgba(255, 181, 71, 0.5);
  color: var(--c-amber);
}
.page-about .ab-timeline__title {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: clamp(1.05rem, 2vw, 1.26rem);
  letter-spacing: -0.01em;
  margin: 0.55rem 0 0.4rem;
  color: var(--c-paper);
}
.page-about .ab-timeline__text {
  margin: 0;
  font-size: 0.94rem;
  line-height: 1.8;
  color: var(--c-text-soft);
  max-width: 54ch;
}
.page-about .ab-timeline__figure {
  margin: clamp(1.8rem, 4vw, 2.6rem) 0 0;
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--c-ink-2);
}
.page-about .ab-timeline__figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}
.page-about .ab-timeline__figure .ab-figcap {
  background: var(--c-ink-2);
  color: var(--c-mist);
}

/* ---------- 团队 ---------- */
.page-about .ab-chapter--tint {
  background: var(--c-ink-2);
  border-top: 1px solid var(--c-line);
  border-bottom: 1px solid var(--c-line);
}
.page-about .ab-team {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 1px;
  margin: clamp(1.4rem, 3.5vw, 2rem) 0;
  background: var(--c-line);
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  overflow: hidden;
}
.page-about .ab-team__cell {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
  padding: 1.1rem 1rem;
  background: var(--c-ink);
}
.page-about .ab-team__num {
  font-size: clamp(1.9rem, 4.5vw, 2.6rem);
  line-height: 1;
  color: var(--c-mint);
}
.page-about .ab-team__label {
  font-size: 0.8rem;
  color: var(--c-mist);
}
.page-about .ab-subhead {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 1rem;
  letter-spacing: 0.02em;
  margin: 0 0 0.9rem;
  color: var(--c-amber);
}
.page-about .ab-lines {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.5rem;
  margin: 0 0 1.3rem;
  padding: 0;
  list-style: none;
}
.page-about .ab-lines__item {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
  padding: 0.6rem 0.75rem;
  font-size: 0.87rem;
  color: var(--c-text-soft);
  border: 1px solid var(--c-line);
  border-radius: var(--radius-sm);
  transition: border-color var(--t) var(--ease), color var(--t) var(--ease);
}
.page-about .ab-lines__item:hover {
  border-color: var(--c-mint);
  color: var(--c-paper);
}
.page-about .ab-lines__idx {
  font-size: 0.72rem;
  color: var(--c-electric);
}

/* ---------- 体验原则 ---------- */
.page-about .ab-principles {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--c-line);
  border-top: 1px solid var(--c-line);
  border-bottom: 1px solid var(--c-line);
}
.page-about .ab-principles__item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  column-gap: 0.9rem;
  row-gap: 0.35rem;
  padding: 1.15rem 0.25rem;
  background: var(--c-ink);
}
.page-about .ab-principles__idx {
  grid-row: span 2;
  font-size: 0.78rem;
  color: var(--c-rose);
  padding-top: 0.28rem;
}
.page-about .ab-principles__title {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 1.02rem;
  margin: 0;
  color: var(--c-paper);
}
.page-about .ab-principles__text {
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.78;
  color: var(--c-text-soft);
  max-width: 54ch;
}

/* ---------- 收束 ---------- */
.page-about .ab-next {
  padding: clamp(3rem, 8vw, 6rem) 0;
  background:
    radial-gradient(120% 90% at 100% 0%, rgba(255, 181, 71, 0.16), transparent 62%),
    var(--c-deep-teal);
  border-top: 1px solid var(--c-line);
  scroll-margin-top: calc(var(--yb-header-h) + 62px);
}
.page-about .ab-next__eyebrow {
  color: var(--c-mint);
  letter-spacing: 0.18em;
}
.page-about .ab-next__title {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(1.9rem, 5.5vw, 3.4rem);
  letter-spacing: -0.03em;
  line-height: 1.08;
  margin: 0.5rem 0 0;
  color: var(--c-paper);
}
.page-about .ab-next__lead {
  margin: clamp(0.9rem, 2.5vw, 1.3rem) 0 0;
  max-width: 52ch;
  font-size: 0.97rem;
  line-height: 1.85;
  color: var(--c-text-soft);
}
.page-about .ab-next__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
  margin-top: clamp(1.4rem, 3.5vw, 2rem);
}

/* ---------- 断点 ---------- */
@media (min-width: 640px) {
  .page-about .ab-hero__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .ab-cells {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .ab-lines {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .ab-paper__foot {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.1fr);
    align-items: center;
  }
}

@media (min-width: 900px) {
  .page-about .ab-hero__inner {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
    gap: clamp(2rem, 4vw, 3.4rem);
  }
  .page-about .ab-chapter__grid {
    grid-template-columns: 132px minmax(0, 1fr);
    gap: clamp(2rem, 4vw, 3.4rem);
  }
  .page-about .ab-chapter__aside {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.35rem;
    position: sticky;
    top: calc(var(--yb-header-h) + 86px);
    align-self: start;
  }
  .page-about .ab-chapter__label {
    padding-top: 0.25rem;
    border-top: 1px solid var(--c-line);
    width: 100%;
  }
  .page-about .ab-cells {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .ab-cell {
    padding: 1.25rem 1rem;
  }
  .page-about .ab-team__cell {
    padding: 1.4rem 1.2rem;
  }
  .page-about .ab-principles__item {
    grid-template-columns: auto minmax(0, 0.42fr) minmax(0, 1fr);
    align-items: baseline;
    column-gap: 1.6rem;
    padding: 1.4rem 0.25rem;
  }
  .page-about .ab-principles__idx {
    grid-row: auto;
    padding-top: 0;
  }
}

@media (min-width: 1100px) {
  .page-about .ab-cells {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }
  .page-about .ab-timeline {
    padding-left: 2.2rem;
  }
  .page-about .ab-timeline__item::before {
    left: calc(-2.2rem - 5px);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-index__link,
  .page-about .ab-cell,
  .page-about .ab-cell__idx,
  .page-about .ab-cell__name,
  .page-about .ab-lines__item,
  .page-about .ab-timeline__item::before {
    transition: none;
  }
}
</final_solution>