.page-about {
  --ab-skew: -3deg;
  --ab-card: rgba(18, 58, 46, .94);
  --ab-card-deep: rgba(14, 42, 34, .94);
}

.page-about img {
  max-width: 100%;
  height: auto;
  display: block;
}

.page-about figure {
  margin: 0;
}

.page-about .ab-crumbs {
  padding-top: clamp(16px, 3vw, 28px);
}

/* ---------- 首屏 ---------- */

.page-about .ab-hero {
  position: relative;
  overflow: hidden;
  padding-top: clamp(20px, 3.4vw, 40px);
}

.page-about .ab-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--line-soft) 1px, transparent 1px),
    linear-gradient(90deg, var(--line-soft) 1px, transparent 1px);
  background-size: 56px 56px;
  -webkit-mask-image: radial-gradient(130% 90% at 18% 0%, #000 0%, transparent 70%);
  mask-image: radial-gradient(130% 90% at 18% 0%, #000 0%, transparent 70%);
  pointer-events: none;
}

.page-about .ab-hero > .container {
  position: relative;
  z-index: 1;
}

.page-about .ab-kicker {
  margin: 0 0 14px;
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--cool);
}

.page-about .ab-title {
  margin: 0 0 18px;
  font-size: clamp(32px, 7.2vw, 64px);
  line-height: 1.04;
  letter-spacing: -0.02em;
  font-weight: 900;
  color: var(--paper);
}

.page-about .ab-title em {
  font-style: normal;
  color: var(--lime);
}

.page-about .ab-lead {
  margin: 0 0 12px;
  font-size: 17px;
  line-height: 1.85;
  color: var(--mist);
  max-width: 62ch;
}

.page-about .ab-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
}

/* ---------- 图片容器 ---------- */

.page-about .ab-figure {
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--field);
  position: relative;
}

.page-about .ab-figure img {
  width: 100%;
  object-fit: cover;
}

.page-about .ab-figure figcaption {
  padding: 12px 16px;
  border-top: 1px solid var(--line);
  font-size: 12px;
  line-height: 1.6;
  letter-spacing: .05em;
  color: var(--mist);
}

.page-about .ab-hero__figure::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--lime), var(--amber), var(--cool));
}

/* ---------- 首屏数据条 ---------- */

.page-about .ab-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 12px;
  margin-top: clamp(30px, 5vw, 56px);
  padding-top: 22px;
  border-top: 1px solid var(--line);
}

.page-about .ab-stat {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(160deg, var(--ab-card), var(--ab-card-deep));
}

.page-about .ab-stat__num {
  font-family: var(--font-num);
  font-size: clamp(26px, 4.8vw, 40px);
  font-weight: 600;
  line-height: 1;
  color: var(--amber);
  font-variant-numeric: tabular-nums;
}

.page-about .ab-stat__label {
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--mist);
}

/* ---------- 章节头 ---------- */

.page-about .ab-ch {
  position: relative;
}

.page-about .ab-head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 14px 20px;
  align-items: start;
  margin-bottom: clamp(22px, 3.4vw, 36px);
}

.page-about .sec-num {
  font-family: var(--font-num);
  font-size: clamp(40px, 9vw, 76px);
  font-weight: 600;
  line-height: .88;
  letter-spacing: -0.04em;
  color: var(--lime);
  -webkit-text-fill-color: transparent;
  -webkit-text-stroke: 1.5px var(--lime);
}

.page-about .sec-title {
  margin: 0 0 10px;
  font-size: clamp(22px, 3.8vw, 34px);
  line-height: 1.26;
  letter-spacing: -0.01em;
  font-weight: 800;
  color: var(--paper);
}

.page-about .sec-lead {
  margin: 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--mist);
  max-width: 62ch;
}

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

/* ---------- 正文 ---------- */

.page-about .prose p {
  margin: 0 0 1.1em;
  font-size: 17px;
  line-height: 1.85;
  color: var(--mist);
}

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

.page-about .prose strong {
  color: var(--paper);
  font-weight: 600;
}

.page-about .ab-prose--tight p {
  font-size: 16px;
}

/* ---------- 01 阶段卡 ---------- */

.page-about .ab-stage {
  padding: 20px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-lg);
  background: linear-gradient(170deg, var(--ab-card), rgba(7, 19, 15, .95));
}

.page-about .ab-stage__title {
  margin: 0 0 16px;
  font-size: 11px;
  letter-spacing: .22em;
  color: var(--cool);
}

.page-about .ab-stage__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .ab-stage__item {
  padding-left: 14px;
  border-left: 2px solid var(--lime);
}

.page-about .ab-stage__k {
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--amber);
}

.page-about .ab-stage__h {
  margin: 4px 0 4px;
  font-size: 16px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .ab-stage__p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--mist);
}

/* ---------- 02 筛选与时间轴 ---------- */

.page-about .ab-filters {
  display: flex;
  gap: 10px;
  overflow-x: auto;
  padding-bottom: 8px;
  margin-bottom: 6px;
}

.page-about .ab-track {
  position: relative;
  display: flex;
  gap: 16px;
  overflow-x: auto;
  padding: 26px 2px 30px;
  scroll-snap-type: x proximity;
  border-top: 1px solid var(--line);
}

.page-about .ab-track::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: -1px;
  height: 3px;
  background: linear-gradient(90deg, var(--lime), var(--amber), var(--cool));
  transform: skewY(var(--ab-skew));
  transform-origin: left center;
  pointer-events: none;
}

.page-about .ab-node {
  flex: 0 0 min(78vw, 300px);
  scroll-snap-align: start;
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 20px 18px 30px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-lg);
  background: linear-gradient(165deg, var(--ab-card), var(--ab-card-deep));
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 22px), calc(100% - 22px) 100%, 0 100%);
  transition: border-color .18s ease, background .18s ease;
}

.page-about .ab-node:target {
  border-color: var(--lime);
  background: linear-gradient(165deg, rgba(24, 74, 58, .96), var(--ab-card-deep));
  box-shadow: inset 0 0 0 1px var(--lime);
}

.page-about .ab-node:target .ab-node__ver {
  color: var(--lime);
}

.page-about .ab-node__top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}

.page-about .ab-node__ver {
  font-family: var(--font-num);
  font-size: 30px;
  font-weight: 600;
  line-height: 1;
  letter-spacing: .02em;
  color: var(--amber);
}

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

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

/* ---------- 能力矩阵 ---------- */

.page-about .ab-matrix-wrap {
  margin-top: clamp(28px, 4.4vw, 48px);
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: var(--field);
  overflow-x: auto;
}

.page-about .ab-matrix__cap {
  margin: 0 0 14px;
  font-size: 11px;
  letter-spacing: .2em;
  color: var(--cool);
}

.page-about .ab-matrix {
  min-width: 620px;
  display: grid;
  gap: 4px;
}

.page-about .ab-mrow {
  display: grid;
  grid-template-columns: 60px repeat(7, minmax(0, 1fr));
  gap: 6px;
  align-items: center;
  padding: 7px 8px;
  border-radius: var(--radius-sm);
  text-decoration: none;
  color: inherit;
  transition: background .16s ease;
}

.page-about .ab-mrow--head {
  padding-bottom: 10px;
}

.page-about .ab-mrow:hover,
.page-about .ab-mrow:focus-visible {
  background: rgba(198, 242, 78, .10);
}

.page-about .ab-mver {
  font-family: var(--font-num);
  font-size: 13px;
  color: var(--paper);
  letter-spacing: .06em;
}

.page-about .ab-mrow--head .ab-mver {
  color: var(--mist);
  font-size: 11px;
  letter-spacing: .14em;
}

.page-about .ab-mcol {
  font-size: 11px;
  line-height: 1.35;
  letter-spacing: .08em;
  text-align: center;
  color: var(--mist);
}

.page-about .ab-cell {
  justify-self: stretch;
  height: 10px;
  border-radius: var(--pill);
  background: rgba(79, 195, 217, .10);
}

.page-about .ab-cell--on {
  background: var(--lime);
}

/* ---------- 03 规模 ---------- */

.page-about .ab-scale-col {
  display: grid;
  gap: 22px;
  align-content: start;
}

.page-about .ab-scale {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 12px;
}

.page-about .ab-scale__item {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(160deg, var(--ab-card), var(--ab-card-deep));
}

.page-about .ab-scale__num {
  font-family: var(--font-num);
  font-size: clamp(20px, 3.2vw, 28px);
  font-weight: 600;
  line-height: 1;
  color: var(--amber);
  font-variant-numeric: tabular-nums;
}

.page-about .ab-scale__label {
  font-size: 12px;
  line-height: 1.5;
  letter-spacing: .1em;
  color: var(--mist);
}

/* ---------- 05 协作 ---------- */

.page-about .ab-coop {
  display: grid;
  gap: 16px;
}

.page-about .ab-coop__item {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 10px;
  padding: 22px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-lg);
  background: linear-gradient(160deg, var(--ab-card), var(--ab-card-deep));
}

.page-about .ab-coop__h {
  margin: 0;
  font-size: 18px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .ab-coop__p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .ab-link {
  font-size: 13px;
  letter-spacing: .1em;
  color: var(--lime);
  text-decoration: none;
  border-bottom: 1px solid var(--line-lime);
  padding-bottom: 2px;
}

.page-about .ab-link:hover,
.page-about .ab-link:focus-visible {
  color: var(--paper);
  border-bottom-color: var(--paper);
}

/* ---------- 结尾引导 ---------- */

.page-about .ab-cta__inner {
  display: grid;
  gap: 22px;
  padding: clamp(24px, 4vw, 40px);
  border: 1px solid var(--line-lime);
  border-radius: var(--radius-lg);
  background:
    radial-gradient(120% 140% at 0% 0%, rgba(198, 242, 78, .14), transparent 62%),
    linear-gradient(160deg, rgba(18, 58, 46, .96), rgba(7, 19, 15, .96));
}

.page-about .ab-cta__title {
  margin: 0 0 10px;
  font-size: clamp(22px, 3.6vw, 32px);
  line-height: 1.25;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .ab-cta__text {
  margin: 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--mist);
  max-width: 58ch;
}

.page-about .ab-cta__links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

/* ---------- 键盘焦点 ---------- */

.page-about a:focus-visible,
.page-about button:focus-visible {
  outline: 2px solid var(--lime);
  outline-offset: 3px;
}

/* ---------- 窄屏收束 ---------- */

@media (max-width: 560px) {
  .page-about .ab-node {
    flex-basis: 82vw;
  }

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

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

/* ---------- 桌面增强 ---------- */

@media (min-width: 768px) {
  .page-about .ab-node {
    flex-basis: 320px;
  }

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

  .page-about .ab-coop__item--wide {
    grid-column: 1 / -1;
  }

  .page-about .ab-matrix-wrap {
    padding: 24px 26px;
  }
}

@media (min-width: 900px) {
  .page-about .ab-cta__inner {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
    align-items: center;
  }

  .page-about .ab-cta__links {
    justify-content: flex-end;
  }
}

@media (min-width: 1024px) {
  .page-about .ab-head {
    grid-template-columns: auto minmax(0, 1fr) auto;
    gap: 16px 28px;
  }

  .page-about .ab-rail {
    display: block;
    align-self: start;
    margin: 6px 0 0;
    writing-mode: vertical-rl;
    font-family: var(--font-num);
    font-size: 11px;
    letter-spacing: .24em;
    color: var(--mist);
    opacity: .8;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-node,
  .page-about .ab-mrow {
    transition: none;
  }
}