.page-about {
  --ab-rail: 116px;
  --ab-rail-gap: 46px;
  background: var(--night-900);
  color: var(--text);
  overflow-x: hidden;
}

.page-about .ab-hero {
  padding: clamp(28px, 5vw, 56px) 0 clamp(30px, 5vw, 52px);
  border-bottom: 1px solid var(--line);
}

.page-about .ab-hero__eyebrow {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.16em;
  color: var(--celadon);
  margin: 0 0 18px;
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.page-about .ab-hero__eyebrow::before {
  content: "";
  width: 26px;
  height: 2px;
  border-radius: var(--r-pill);
  background: var(--amber);
}

.page-about .ab-hero__title {
  font-size: clamp(28px, 5.2vw, 46px);
  line-height: 1.24;
  font-weight: 800;
  letter-spacing: -0.012em;
  color: #FFFFFF;
  margin: 0 0 20px;
  max-width: 17em;
}

.page-about .ab-hero__lead {
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.85;
  color: var(--text-dim);
  max-width: 44em;
  margin: 0;
}

.page-about .ab-stats {
  list-style: none;
  margin: 34px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
}

.page-about .ab-stats__item {
  background: var(--night-800);
  border: 1px solid var(--line);
  border-radius: var(--r-card);
  padding: 14px 16px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  transition: border-color 180ms var(--ease), transform 180ms var(--ease);
}

.page-about .ab-stats__item:hover {
  border-color: var(--line-strong);
  transform: translateY(-2px);
}

.page-about .ab-stats__num {
  font-family: var(--font-mono);
  font-size: clamp(18px, 3.4vw, 26px);
  font-weight: 700;
  line-height: 1.1;
  color: var(--amber);
  letter-spacing: 0.01em;
}

.page-about .ab-stats__label {
  font-size: 12.5px;
  line-height: 1.5;
  color: var(--text-dim);
}

/* ---------- 纵向刻度时间线 ---------- */

.page-about .ab-timeline {
  position: relative;
  margin-top: clamp(34px, 5.5vw, 60px);
}

.page-about .ab-phase {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  position: relative;
  padding-bottom: clamp(36px, 5vw, 58px);
}

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

.page-about .ab-phase__rail {
  display: flex;
  align-items: center;
  gap: 10px;
}

.page-about .ab-phase__idx {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--night-900);
  background: var(--amber);
  border-radius: var(--r-pill);
  min-width: 46px;
  padding: 6px 12px;
  text-align: center;
  position: relative;
  z-index: 1;
  box-shadow: 0 0 0 6px var(--night-900);
}

.page-about .ab-phase__tag {
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.12em;
  color: var(--text-dim);
  padding: 5px 11px;
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  background: rgba(20, 40, 74, 0.6);
  white-space: nowrap;
}

.page-about .ab-phase__body {
  min-width: 0;
}

.page-about .ab-phase__title {
  font-size: clamp(20px, 2.8vw, 27px);
  font-weight: 800;
  line-height: 1.32;
  letter-spacing: -0.008em;
  color: #FFFFFF;
  margin: 0 0 14px;
}

.page-about .ab-phase__lead {
  font-size: 15.5px;
  line-height: 1.9;
  color: var(--text-dim);
  margin: 0 0 22px;
  max-width: 44em;
}

.page-about .ab-phase__tail {
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--text-dim);
  margin: 22px 0 0;
  padding-left: 14px;
  border-left: 3px solid var(--night-700);
}

.page-about .ab-phase__tail a {
  color: var(--celadon);
  text-decoration: none;
  border-bottom: 1px solid rgba(63, 208, 175, 0.4);
  transition: color 160ms var(--ease), border-color 160ms var(--ease);
}

.page-about .ab-phase__tail a:hover {
  color: var(--celadon-light);
  border-bottom-color: var(--celadon-light);
}

/* ---------- 01 三块能力点 ---------- */

.page-about .ab-points {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.page-about .ab-point {
  background: var(--night-800);
  border: 1px solid var(--line);
  border-radius: var(--r-card);
  padding: 18px 18px 20px;
  transition: border-color 180ms var(--ease), transform 180ms var(--ease);
}

.page-about .ab-point:hover {
  border-color: var(--line-strong);
  transform: translateY(-2px);
}

.page-about .ab-point h3 {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--celadon);
  margin: 0 0 10px;
}

.page-about .ab-point p {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--text-dim);
}

/* ---------- 02 规模 + 数据条 ---------- */

.page-about .ab-figure {
  margin: 0 0 24px;
  border-radius: var(--r-card);
  overflow: hidden;
  background: var(--night-800);
  border: 1px solid var(--line);
}

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

.page-about .ab-figure figcaption {
  padding: 12px 18px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  line-height: 1.65;
  color: var(--text-dim);
  border-top: 1px solid var(--line);
}

.page-about .ab-scale {
  list-style: none;
  margin: 0 0 22px;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
}

.page-about .ab-scale__item {
  display: grid;
  grid-template-columns: 68px 1fr;
  gap: 14px;
  align-items: center;
  background: linear-gradient(90deg, rgba(63, 208, 175, 0.09), rgba(20, 40, 74, 0.5) 42%);
  border: 1px solid var(--line);
  border-radius: var(--r-card);
  padding: 14px 18px;
}

.page-about .ab-scale__n {
  font-family: var(--font-mono);
  font-size: 26px;
  font-weight: 700;
  line-height: 1;
  color: var(--celadon);
  letter-spacing: 0.01em;
}

.page-about .ab-scale__u {
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--text-dim);
}

.page-about .ab-meters {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
}

.page-about .ab-meter {
  display: grid;
  grid-template-columns: 82px 1fr;
  gap: 16px;
  align-items: baseline;
  background: var(--night-800);
  border: 1px solid var(--line);
  border-radius: var(--r-card);
  padding: 14px 18px;
  transition: border-color 180ms var(--ease);
}

.page-about .ab-meter:hover {
  border-color: var(--line-strong);
}

.page-about .ab-meter__num {
  font-family: var(--font-mono);
  font-size: 20px;
  font-weight: 700;
  line-height: 1.1;
  color: var(--amber);
  letter-spacing: 0.01em;
  white-space: nowrap;
}

.page-about .ab-meter__text {
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--text-dim);
}

/* ---------- 03 值班明细 ---------- */

.page-about .ab-figure--narrow {
  max-width: 640px;
}

.page-about .ab-duty {
  border: 1px solid var(--line);
  border-radius: var(--r-card);
  overflow: hidden;
  background: var(--night-800);
}

.page-about .ab-duty__row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 4px;
  padding: 13px 18px;
  border-bottom: 1px solid var(--line);
}

.page-about .ab-duty__row:last-child {
  border-bottom: 0;
}

.page-about .ab-duty__k {
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.1em;
  color: var(--amber);
}

.page-about .ab-duty__v {
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-dim);
}

/* ---------- 04 机构场景卡 ---------- */

.page-about .ab-scenes {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.page-about .ab-scene {
  background: var(--night-800);
  border: 1px solid var(--line);
  border-radius: var(--r-card);
  padding: 18px;
  position: relative;
  transition: border-color 180ms var(--ease), transform 180ms var(--ease);
}

.page-about .ab-scene:hover {
  border-color: var(--line-strong);
  transform: translateY(-2px);
}

.page-about .ab-scene::after {
  content: "";
  position: absolute;
  left: 18px;
  right: 18px;
  top: 0;
  height: 3px;
  border-radius: var(--r-pill);
  background: linear-gradient(90deg, var(--celadon), transparent);
  opacity: 0;
  transition: opacity 180ms var(--ease);
}

.page-about .ab-scene:hover::after {
  opacity: 1;
}

.page-about .ab-scene__tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.12em;
  color: var(--celadon-light);
  background: rgba(63, 208, 175, 0.12);
  border-radius: var(--r-pill);
  padding: 4px 10px;
  margin-bottom: 12px;
}

.page-about .ab-scene__title {
  font-size: 16px;
  font-weight: 700;
  line-height: 1.5;
  color: #FFFFFF;
  margin: 0 0 10px;
}

.page-about .ab-scene p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--text-dim);
}

/* ---------- 05 用户结构 ---------- */

.page-about .ab-users {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.page-about .ab-user-card {
  background: var(--night-800);
  border: 1px solid var(--line);
  border-left: 3px solid var(--celadon);
  border-radius: var(--r-card);
  padding: 22px 20px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.page-about .ab-user-card--amber {
  background: linear-gradient(135deg, rgba(255, 176, 32, 0.13), rgba(20, 40, 74, 0.85));
  border-left-color: var(--amber);
}

.page-about .ab-user-card__num {
  font-family: var(--font-mono);
  font-size: clamp(30px, 6vw, 44px);
  font-weight: 700;
  line-height: 1;
  color: #FFFFFF;
  letter-spacing: -0.01em;
}

.page-about .ab-user-card--amber .ab-user-card__num {
  color: var(--amber);
}

.page-about .ab-user-card__plus {
  font-size: 0.5em;
  vertical-align: super;
  margin-left: 2px;
  color: var(--celadon);
}

.page-about .ab-user-card--amber .ab-user-card__plus {
  color: var(--amber-soft);
}

.page-about .ab-user-card__label {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text-dim);
}

/* ---------- 06 路线清单 ---------- */

.page-about .ab-road {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
}

.page-about .ab-road__item {
  display: grid;
  grid-template-columns: 44px 1fr;
  gap: 14px;
  padding: 18px 0;
  border-top: 1px solid var(--line);
}

.page-about .ab-road__item:last-child {
  border-bottom: 1px solid var(--line);
}

.page-about .ab-road__idx {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--night-900);
  background: var(--amber);
  border-radius: var(--r-pill);
  height: 26px;
  line-height: 26px;
  text-align: center;
  margin-top: 2px;
}

.page-about .ab-road__body {
  min-width: 0;
}

.page-about .ab-road__title {
  font-size: 16px;
  font-weight: 700;
  line-height: 1.5;
  color: #FFFFFF;
  margin: 0 0 8px;
}

.page-about .ab-road__body p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--text-dim);
}

/* ---------- 结尾 CTA ---------- */

.page-about .ab-cta {
  margin-top: clamp(34px, 5vw, 58px);
  background: linear-gradient(120deg, rgba(31, 59, 105, 0.85), rgba(20, 40, 74, 0.7));
  border: 1px solid var(--line-strong);
  border-radius: var(--r-lg);
  padding: clamp(24px, 4vw, 38px);
  display: grid;
  grid-template-columns: 1fr;
  gap: 22px;
}

.page-about .ab-cta__title {
  font-size: clamp(19px, 2.6vw, 24px);
  font-weight: 800;
  line-height: 1.4;
  color: #FFFFFF;
  margin: 0 0 10px;
}

.page-about .ab-cta__text p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--text-dim);
  max-width: 40em;
}

.page-about .ab-cta__text a {
  color: var(--celadon);
  text-decoration: none;
  border-bottom: 1px solid rgba(63, 208, 175, 0.4);
}

.page-about .ab-cta__text a:hover {
  color: var(--celadon-light);
}

.page-about .ab-cta__links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: flex-start;
}

/* ---------- 响应式 ---------- */

@media (min-width: 600px) {
  .page-about .ab-points {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

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

  .page-about .ab-duty__row {
    grid-template-columns: 110px 1fr;
    gap: 18px;
    align-items: baseline;
  }

  .page-about .ab-cta {
    grid-template-columns: 1fr auto;
    align-items: center;
    gap: 28px;
  }

  .page-about .ab-cta__links {
    flex-direction: column;
    align-items: stretch;
  }
}

@media (min-width: 880px) {
  .page-about {
    --ab-rail: 132px;
    --ab-rail-gap: 48px;
  }

  .page-about .ab-phase {
    grid-template-columns: var(--ab-rail) 1fr;
    gap: var(--ab-rail-gap);
    padding-bottom: 62px;
  }

  .page-about .ab-phase__rail {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }

  .page-about .ab-timeline::before {
    content: "";
    position: absolute;
    left: 22px;
    top: 12px;
    bottom: 30px;
    width: 1px;
    background: linear-gradient(to bottom, var(--line-strong), var(--line) 62%, rgba(31, 59, 105, 0) 100%);
    pointer-events: none;
  }

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

  .page-about .ab-scale__item {
    grid-template-columns: 1fr;
    gap: 8px;
    align-items: start;
    padding: 18px;
  }
}

@media (min-width: 1080px) {
  .page-about .ab-hero {
    display: grid;
    grid-template-columns: minmax(0, 1fr);
  }

  .page-about .ab-cta {
    padding: 44px 46px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-stats__item,
  .page-about .ab-point,
  .page-about .ab-scene,
  .page-about .ab-meter {
    transition: none;
  }

  .page-about .ab-stats__item:hover,
  .page-about .ab-point:hover,
  .page-about .ab-scene:hover {
    transform: none;
  }
}