.page-about{
  --ab-rule: rgba(135,146,168,.32);
  --ab-rule-soft: rgba(135,146,168,.18);
  --ab-on-dark-rule: rgba(245,242,234,.16);
  --ab-orange-wash: rgba(228,116,43,.14);
  --ab-green-wash: rgba(47,139,114,.14);
  --ab-indigo-wash: rgba(51,71,122,.16);
  background: var(--cream);
  color: var(--stone);
  overflow-x: hidden;
}

.page-about .ab-section{
  padding: clamp(48px,7vw,96px) 0;
  position: relative;
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero{
  position: relative;
  background: var(--night);
  color: var(--on-dark);
  padding-bottom: clamp(40px,6vw,84px);
  overflow: hidden;
}

.page-about .ab-hero::before{
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, rgba(135,146,168,.13) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(135,146,168,.13) 1px, transparent 1px);
  background-size: 72px 72px;
  pointer-events: none;
}

.page-about .ab-hero__crumb{
  position: relative;
  z-index: 2;
  padding: 18px 0 4px;
}

.page-about .ab-hero__crumb,
.page-about .ab-hero__crumb a,
.page-about .ab-hero__crumb span{
  color: rgba(245,242,234,.62);
  font-size: 13px;
}

.page-about .ab-hero__crumb a{
  text-decoration: none;
  border-bottom: 1px solid rgba(245,242,234,.28);
}

.page-about .ab-hero__crumb a:hover{
  color: var(--orange-soft);
  border-bottom-color: var(--orange-soft);
}

.page-about .ab-hero__grid{
  position: relative;
  z-index: 2;
  display: grid;
  grid-template-columns: minmax(0,1fr);
  gap: clamp(28px,4vw,52px);
  align-items: start;
  padding-top: clamp(20px,3vw,40px);
}

.page-about .ab-hero h1{
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(30px,6.2vw,58px);
  line-height: 1.08;
  letter-spacing: -.02em;
  color: var(--on-dark-strong);
  margin: 14px 0 0;
}

.page-about .ab-hero .eyebrow{
  color: var(--orange-soft);
}

.page-about .ab-hero__lede{
  margin: clamp(18px,2.4vw,26px) 0 0;
  font-size: clamp(15px,1.6vw,17px);
  line-height: 1.78;
  color: rgba(245,242,234,.80);
  max-width: 46ch;
}

.page-about .ab-hero__facts{
  display: grid;
  grid-template-columns: repeat(3, minmax(0,1fr));
  gap: 1px;
  background: var(--ab-on-dark-rule);
  border-top: 1px solid var(--ab-on-dark-rule);
  border-bottom: 1px solid var(--ab-on-dark-rule);
  margin: clamp(24px,3.6vw,36px) 0 0;
}

.page-about .ab-hero__facts > div{
  background: var(--night);
  padding: 14px 12px 16px;
}

.page-about .ab-hero__facts dt{
  margin: 0;
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--grid);
}

.page-about .ab-hero__facts dd{
  margin: 8px 0 0;
  font-size: clamp(15px,2vw,20px);
  font-weight: 700;
  color: var(--on-dark-strong);
}

.page-about .ab-hero__actions{
  margin-top: clamp(22px,3vw,32px);
}

.page-about .ab-hero__media{
  margin: 0;
  position: relative;
}

.page-about .ab-hero__media img{
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 5;
  object-fit: cover;
}

/* ---------- 通用区块标题的底色适配 ---------- */
.page-about .ab-section .section-head{
  max-width: 62ch;
  margin-bottom: clamp(26px,3.6vw,44px);
}

.page-about .ab-section .eyebrow{
  color: var(--orange);
}

/* ---------- 推进轨迹 ---------- */
.page-about .ab-history{
  background: var(--cream);
}

.page-about .ab-history__tabs{
  display: block;
}

.page-about .ab-history__switch{
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: clamp(24px,3vw,36px);
}

.page-about .ab-history__switch .tabs__btn{
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .02em;
  padding: 9px 16px;
  border: 1px solid var(--ab-rule);
  background: transparent;
  color: var(--stone);
  cursor: pointer;
  transition: background-color .18s var(--ease), color .18s var(--ease), border-color .18s var(--ease);
}

.page-about .ab-history__switch .tabs__btn:hover{
  border-color: var(--orange);
  color: var(--orange);
}

.page-about .ab-history__switch .tabs__btn[aria-selected="true"]{
  background: var(--night);
  border-color: var(--night);
  color: var(--on-dark-strong);
  box-shadow: inset 0 -2px 0 var(--orange);
}

.page-about .ab-track{
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .ab-track__item{
  position: relative;
  padding: 0 0 clamp(24px,3vw,34px) 30px;
}

.page-about .ab-track__item::before{
  content: "";
  position: absolute;
  left: 5px;
  top: 16px;
  bottom: 0;
  width: 1px;
  background: var(--ab-rule);
}

.page-about .ab-track__item:last-child::before{
  display: none;
}

.page-about .ab-track__node{
  position: absolute;
  left: 0;
  top: 6px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--orange);
  box-shadow: 0 0 0 4px rgba(228,116,43,.16);
}

.page-about .ab-track__label{
  margin: 0;
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--orange);
}

.page-about .ab-track__title{
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(19px,2.4vw,26px);
  line-height: 1.28;
  letter-spacing: -.01em;
  color: var(--night);
  margin: 8px 0 0;
}

.page-about .ab-track__text{
  margin: 10px 0 0;
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--stone);
  max-width: 60ch;
}

.page-about .ab-track__metric{
  display: inline-block;
  margin: 14px 0 0;
  padding: 6px 12px;
  font-size: 12.5px;
  letter-spacing: .02em;
  color: var(--green-deep);
  background: var(--ab-green-wash);
  border-left: 2px solid var(--green);
}

.page-about .ab-history__media{
  margin: clamp(32px,4vw,56px) 0 0;
  position: relative;
  width: 100%;
}

.page-about .ab-history__media img{
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 7;
  object-fit: cover;
}

/* ---------- 校订团队 ---------- */
.page-about .ab-team{
  background: var(--night-2);
  color: var(--on-dark);
}

.page-about .ab-team .section-head__title,
.page-about .ab-team .section-head__note{
  color: var(--on-dark-strong);
}

.page-about .ab-team .section-head__note{
  color: rgba(245,242,234,.74);
}

.page-about .ab-role-band{
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0,1fr);
  gap: 1px;
  background: var(--ab-on-dark-rule);
  border: 1px solid var(--ab-on-dark-rule);
}

.page-about .ab-role-band__item{
  background: var(--night-2);
  padding: clamp(22px,3vw,32px);
  position: relative;
  border-top: 3px solid var(--night-3);
}

.page-about .ab-role-band__item--intake{
  border-top-color: var(--orange);
}

.page-about .ab-role-band__item--compare{
  border-top-color: var(--green);
}

.page-about .ab-role-band__item--review{
  border-top-color: var(--grid);
}

.page-about .ab-role-band__count{
  margin: 0;
  font-size: 13px;
  letter-spacing: .08em;
  color: var(--on-dark-strong);
}

.page-about .ab-role-band__title{
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(18px,2.2vw,23px);
  line-height: 1.3;
  color: var(--on-dark-strong);
  margin: 10px 0 0;
}

.page-about .ab-role-band__text{
  margin: 10px 0 0;
  font-size: 15px;
  line-height: 1.78;
  color: rgba(245,242,234,.76);
}

.page-about .ab-role-band__foot{
  margin: 16px 0 0;
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--grid);
  padding-top: 12px;
  border-top: 1px solid var(--ab-on-dark-rule);
}

.page-about .ab-team__note{
  margin-top: clamp(30px,4vw,48px);
  padding: clamp(22px,3vw,32px);
  background: var(--night);
  border-left: 3px solid var(--orange);
}

.page-about .ab-team__note h3{
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(17px,2vw,21px);
  color: var(--on-dark-strong);
  margin: 0;
}

.page-about .ab-team__note p{
  margin: 12px 0 0;
  font-size: 15px;
  line-height: 1.78;
  color: rgba(245,242,234,.76);
  max-width: 68ch;
}

/* ---------- 三道工序 ---------- */
.page-about .ab-process{
  background: var(--cream);
}

.page-about .ab-steps{
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0,1fr);
  gap: 1px;
  background: var(--ab-rule);
  border-top: 1px solid var(--ab-rule);
  border-bottom: 1px solid var(--ab-rule);
}

.page-about .ab-steps__item{
  background: var(--cream);
  padding: clamp(22px,3vw,34px) 0;
  display: grid;
  grid-template-columns: auto minmax(0,1fr);
  gap: clamp(14px,2.4vw,28px);
  align-items: start;
}

.page-about .ab-steps__num{
  font-size: clamp(22px,3vw,34px);
  font-weight: 700;
  line-height: 1;
  color: var(--orange);
  letter-spacing: -.02em;
}

.page-about .ab-steps__title{
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(18px,2.2vw,24px);
  line-height: 1.32;
  color: var(--night);
  margin: 0;
}

.page-about .ab-steps__text{
  margin: 10px 0 0;
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--stone);
  max-width: 62ch;
}

.page-about .ab-steps__detail{
  margin: 12px 0 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--green-deep);
  padding-left: 12px;
  border-left: 2px solid var(--green-soft);
  max-width: 58ch;
  transition: transform .18s var(--ease);
}

.page-about .ab-process__media{
  margin: clamp(30px,4vw,52px) 0 0;
  position: relative;
}

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

/* ---------- 档案规模 ---------- */
.page-about .ab-scale{
  background: var(--night);
  color: var(--on-dark);
}

.page-about .ab-scale .section-head__title{
  color: var(--on-dark-strong);
}

.page-about .ab-scale .section-head__note{
  color: rgba(245,242,234,.72);
}

.page-about .ab-scale__grid{
  display: grid;
  grid-template-columns: minmax(0,1fr);
  gap: 1px;
  background: var(--ab-on-dark-rule);
  border: 1px solid var(--ab-on-dark-rule);
}

.page-about .ab-scale__cell{
  background: var(--night-2);
  padding: clamp(24px,3.4vw,38px);
}

.page-about .ab-scale__label{
  margin: 0;
  font-size: 13px;
  letter-spacing: .08em;
  color: var(--grid);
}

.page-about .ab-scale__value{
  margin: 14px 0 0;
  font-size: clamp(38px,7vw,62px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.03em;
  color: var(--on-dark-strong);
}

.page-about .ab-scale__suffix{
  font-size: .5em;
  color: var(--orange);
  margin-left: 2px;
}

.page-about .ab-scale__unit{
  margin: 14px 0 0;
  font-size: 13.5px;
  line-height: 1.6;
  color: rgba(245,242,234,.66);
}

.page-about .ab-scale__extra{
  list-style: none;
  margin: clamp(28px,3.6vw,44px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0,1fr);
  gap: 0;
  border-top: 1px solid var(--ab-on-dark-rule);
}

.page-about .ab-scale__extra li{
  padding: 16px 0;
  border-bottom: 1px solid var(--ab-on-dark-rule);
  font-size: 15px;
  line-height: 1.7;
  color: rgba(245,242,234,.78);
  display: flex;
  align-items: baseline;
  gap: 12px;
}

.page-about .ab-scale__extra li .mono{
  color: var(--orange-soft);
  font-weight: 700;
  font-size: 16px;
  min-width: 4.5em;
  flex: none;
}

/* ---------- 来源与引用 ---------- */
.page-about .ab-source{
  background: var(--cream);
}

.page-about .ab-source__grid{
  display: grid;
  grid-template-columns: minmax(0,1fr);
  gap: clamp(30px,4vw,54px);
  align-items: start;
}

.page-about .ab-source__intro .section-head{
  margin-bottom: clamp(16px,2vw,24px);
}

.page-about .ab-source__text{
  margin: 0;
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--stone);
  max-width: 58ch;
}

.page-about .ab-source__text--sub{
  margin-top: 18px;
  font-size: 14px;
  color: var(--stone);
}

.page-about .ab-source__text a{
  color: var(--green-deep);
  text-decoration: none;
  border-bottom: 1px solid var(--green-soft);
}

.page-about .ab-source__text a:hover{
  color: var(--orange);
  border-bottom-color: var(--orange);
}

.page-about .ab-source__list{
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  border-top: 1px solid var(--ab-rule);
}

.page-about .ab-source__list li{
  display: flex;
  gap: 14px;
  align-items: baseline;
  padding: 12px 0;
  border-bottom: 1px solid var(--ab-rule-soft);
  font-size: 15px;
  color: var(--night);
}

.page-about .ab-source__list li .mono{
  color: var(--grid);
  font-size: 12.5px;
  flex: none;
}

.page-about .ab-cite{
  background: var(--night);
  padding: clamp(22px,3vw,32px);
  color: var(--on-dark);
}

.page-about .ab-cite__label{
  margin: 0 0 14px;
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--orange-soft);
}

.page-about .ab-cite__code{
  margin: 0;
  padding: 18px 20px;
  background: var(--night-deep);
  border-left: 3px solid var(--orange);
  font-size: 13px;
  line-height: 2;
  color: var(--on-dark-strong);
  overflow-x: auto;
  white-space: pre;
}

.page-about .ab-cite__code code{
  font-family: inherit;
}

.page-about .ab-cite__note{
  margin: 16px 0 0;
  font-size: 13.5px;
  line-height: 1.75;
  color: rgba(245,242,234,.72);
}

/* ---------- 合作生态 ---------- */
.page-about .ab-partners{
  background: var(--night-deep);
  color: var(--on-dark);
}

.page-about .ab-partners .section-head__title{
  color: var(--on-dark-strong);
}

.page-about .ab-partners__grid{
  display: grid;
  grid-template-columns: minmax(0,1fr);
  gap: 1px;
  background: var(--ab-on-dark-rule);
  border: 1px solid var(--ab-on-dark-rule);
}

.page-about .ab-partners__card{
  background: var(--night-deep);
  padding: clamp(24px,3.2vw,36px);
}

.page-about .ab-partners__count{
  margin: 0;
  font-size: clamp(34px,5vw,46px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.03em;
  color: var(--green-soft);
}

.page-about .ab-partners__card h3{
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(17px,2vw,21px);
  line-height: 1.32;
  color: var(--on-dark-strong);
  margin: 14px 0 0;
}

.page-about .ab-partners__card p{
  margin: 10px 0 0;
  font-size: 15px;
  line-height: 1.78;
  color: rgba(245,242,234,.74);
}

.page-about .ab-partners__cta{
  margin-top: clamp(30px,4vw,48px);
  padding: clamp(22px,3vw,32px);
  background: var(--orange);
  color: #1a1206;
}

.page-about .ab-partners__cta p{
  margin: 0;
  font-size: clamp(15px,1.8vw,17px);
  line-height: 1.7;
  max-width: 62ch;
  font-weight: 600;
}

.page-about .ab-partners__cta .btn-row{
  margin-top: 20px;
}

.page-about .ab-partners__cta .btn--primary{
  background: var(--night);
  border-color: var(--night);
  color: var(--on-dark-strong);
}

.page-about .ab-partners__cta .btn--outline{
  border-color: rgba(26,18,6,.5);
  color: #1a1206;
}

/* ---------- 响应式 ---------- */
@media (min-width: 700px){
  .page-about .ab-role-band{
    grid-template-columns: repeat(3, minmax(0,1fr));
  }

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

  .page-about .ab-scale__extra{
    grid-template-columns: repeat(2, minmax(0,1fr));
    column-gap: clamp(20px,3vw,44px);
  }

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

@media (min-width: 960px){
  .page-about .ab-hero__grid{
    grid-template-columns: minmax(0,1.12fr) minmax(0,.88fr);
    gap: clamp(36px,5vw,72px);
  }

  .page-about .ab-hero__media{
    margin-top: clamp(8px,2vw,26px);
  }

  .page-about .ab-track{
    max-width: 72ch;
  }

  .page-about .ab-track__item{
    display: grid;
    grid-template-columns: minmax(0,1fr);
  }

  .page-about .ab-source__grid{
    grid-template-columns: minmax(0,1.05fr) minmax(0,.95fr);
  }

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

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

@media (min-width: 1180px){
  .page-about .ab-steps__item{
    grid-template-columns: 96px minmax(0,1fr);
  }
}

@media (prefers-reduced-motion: reduce){
  .page-about *{
    transition-duration: .01ms !important;
    animation-duration: .01ms !important;
  }
}
</main>