.page-about{
  --about-max:1280px;
  --about-paper-line:rgba(92,102,95,.20);
  --about-paper-line-strong:rgba(92,102,95,.38);
  --about-dark-line:rgba(199,208,202,.22);
  --about-body:#243029;
  background:var(--paper);
  color:var(--ink);
  font-family:var(--font-body);
  overflow-x:clip;
}

/* ---------- 首屏 ---------- */
.page-about .hero{
  position:relative;
  isolation:isolate;
  background:
    radial-gradient(92% 74% at 92% 2%,rgba(46,91,71,.92),rgba(8,37,31,0) 62%),
    linear-gradient(168deg,#08251F 0%,#0E2F27 56%,#08251F 100%);
  color:var(--paper);
  padding-block:clamp(22px,4vw,40px) clamp(58px,8vw,104px);
}
.page-about .hero::before{
  content:"";
  position:absolute;
  z-index:0;
  top:0;
  right:-8%;
  width:48%;
  height:100%;
  background:linear-gradient(180deg,rgba(255,90,31,.18),rgba(255,90,31,0) 74%);
  clip-path:polygon(26% 0,100% 0,100% 100%,0 100%);
  pointer-events:none;
}
.page-about .hero::after{
  content:"";
  position:absolute;
  z-index:0;
  left:0;
  right:0;
  bottom:-1px;
  height:clamp(34px,6vw,74px);
  background:var(--paper);
  clip-path:polygon(0 100%,100% 0,100% 100%,0 100%);
  pointer-events:none;
}
.page-about .hero .shell{
  position:relative;
  z-index:1;
}
.page-about .hero__grid{
  display:grid;
  gap:clamp(28px,4vw,48px);
  margin-top:clamp(26px,4vw,50px);
}
.page-about .hero h1{
  font-family:var(--font-display);
  font-weight:800;
  font-size:clamp(34px,6.6vw,72px);
  line-height:1.03;
  letter-spacing:-.02em;
  margin:clamp(14px,2vw,22px) 0 0;
  max-width:16ch;
}
.page-about .hero__lede{
  margin-top:clamp(16px,2.2vw,24px);
  max-width:46ch;
  color:rgba(245,240,228,.80);
  font-size:clamp(16px,1.6vw,18px);
  line-height:1.85;
}
.page-about .hero__actions{
  display:flex;
  flex-wrap:wrap;
  gap:12px;
  margin-top:clamp(22px,3vw,32px);
}
.page-about .hero__facts{
  position:relative;
  background:rgba(199,208,202,.07);
  border:1px solid var(--about-dark-line);
  border-top:2px solid var(--signal);
  padding:clamp(18px,2.4vw,26px);
  backdrop-filter:blur(6px);
}
.page-about .hero__facts-label{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:var(--steel);
  margin:0 0 12px;
}
.page-about .facts{
  margin:0;
}
.page-about .facts__row{
  display:flex;
  flex-wrap:wrap;
  align-items:baseline;
  justify-content:space-between;
  gap:6px 16px;
  padding:11px 0;
  border-bottom:1px solid var(--about-dark-line);
}
.page-about .facts__row:last-child{
  border-bottom:0;
  padding-bottom:0;
}
.page-about .facts dt{
  font-size:13px;
  letter-spacing:.04em;
  color:rgba(199,208,202,.86);
}
.page-about .facts dd{
  margin:0;
  font-size:14px;
  color:var(--paper);
}
.page-about .facts dd .num{
  font-size:17px;
  font-weight:600;
  color:var(--ember);
}

/* ---------- 档案区骨架 ---------- */
.page-about .dossier{
  padding-block:clamp(34px,5vw,68px) clamp(48px,7vw,96px);
}
.page-about .dossier__grid{
  display:grid;
  gap:clamp(24px,3.6vw,44px);
}
.page-about .dossier__index .eyebrow{
  margin:0 0 10px;
}
.page-about .dossier__index ol{
  display:flex;
  gap:8px;
  margin:0;
  padding:0 0 8px;
  list-style:none;
  overflow-x:auto;
  -webkit-overflow-scrolling:touch;
}
.page-about .index-link{
  display:flex;
  align-items:baseline;
  gap:8px;
  padding:9px 12px;
  border:1px solid var(--about-paper-line);
  border-left:2px solid transparent;
  font-size:14px;
  color:var(--ink);
  text-decoration:none;
  white-space:nowrap;
  transition:border-color var(--dur-fast) var(--ease),background-color var(--dur-fast) var(--ease),color var(--dur-fast) var(--ease);
}
.page-about .index-link .num{
  font-size:12px;
  color:var(--clay);
}
.page-about .index-link:hover,
.page-about .index-link:focus-visible{
  border-color:var(--signal);
  border-left-color:var(--signal);
  background:var(--signal-wash);
  color:var(--ink);
  outline:none;
}
.page-about .index-link:focus-visible{
  box-shadow:0 0 0 2px rgba(255,90,31,.42);
}

/* ---------- 章节 ---------- */
.page-about .chapter{
  padding-block:clamp(34px,4.6vw,60px);
  border-top:1px solid var(--about-paper-line);
}
.page-about .chapter__head{
  display:flex;
  align-items:baseline;
  gap:clamp(12px,2vw,22px);
  margin-bottom:clamp(18px,2.6vw,28px);
}
.page-about .chapter__no{
  flex:none;
  font-family:var(--font-display);
  font-weight:800;
  font-size:clamp(40px,7vw,80px);
  line-height:.82;
  letter-spacing:-.04em;
  color:var(--clay);
  transform:translateX(-.06em);
}
.page-about .chapter__title{
  font-family:var(--font-editorial);
  font-weight:700;
  font-size:clamp(22px,3.4vw,34px);
  line-height:1.32;
  letter-spacing:-.01em;
  margin:0;
  color:var(--ink);
}
.page-about .chapter__body p{
  font-size:17px;
  line-height:1.9;
  color:var(--about-body);
  margin:0 0 1.05em;
}
.page-about .chapter__body p:last-child{
  margin-bottom:0;
}
.page-about .prose{
  max-width:720px;
}
.page-about .chapter__intro{
  max-width:700px;
  padding-left:14px;
  border-left:2px solid var(--steel);
  font-size:17px;
  line-height:1.85;
  color:var(--about-body);
  margin:0 0 clamp(22px,3vw,32px);
}
.page-about .inline-link{
  color:var(--moss);
  text-decoration:none;
  border-bottom:1px solid rgba(46,91,71,.42);
  transition:color var(--dur-fast) var(--ease),border-color var(--dur-fast) var(--ease);
}
.page-about .inline-link:hover,
.page-about .inline-link:focus-visible{
  color:var(--signal);
  border-bottom-color:var(--signal);
}

/* ---------- 图片 ---------- */
.page-about .shot{
  margin:clamp(24px,3.4vw,38px) 0 0;
  border:1px solid var(--about-paper-line);
  background:var(--moss-wash);
}
.page-about .shot__img{
  display:block;
  width:100%;
  height:auto;
  max-width:100%;
  object-fit:cover;
  filter:saturate(.94) contrast(1.02);
}
.page-about .shot__cap{
  font-family:var(--font-mono);
  font-size:12px;
  line-height:1.6;
  letter-spacing:.02em;
  color:var(--slate);
  padding:10px 14px;
  border-top:1px solid var(--about-paper-line);
  background:rgba(199,208,202,.18);
}
.page-about .shot--band{
  margin-top:0;
  margin-bottom:clamp(24px,3.4vw,38px);
}
.page-about .shot--tight{
  max-width:620px;
}

/* ---------- 团队 ---------- */
.page-about .crew{
  display:grid;
  gap:clamp(14px,2vw,20px);
  margin:0 0 clamp(24px,3.4vw,34px);
  padding:0;
  list-style:none;
}
.page-about .crew__item{
  position:relative;
  padding:clamp(18px,2.4vw,26px);
  background:var(--paper);
  border:1px solid var(--about-paper-line);
  border-left:3px solid var(--moss);
}
.page-about .crew__num{
  display:block;
  font-family:var(--font-mono);
  font-size:clamp(30px,4.4vw,44px);
  font-weight:600;
  line-height:1;
  color:var(--signal);
}
.page-about .crew__title{
  font-family:var(--font-body);
  font-size:17px;
  font-weight:700;
  letter-spacing:.02em;
  margin:8px 0 6px;
  color:var(--ink);
}
.page-about .crew__item p{
  font-size:15px;
  line-height:1.78;
  color:var(--slate);
  margin:0;
}
.page-about .crew__item p .num{
  color:var(--moss);
  font-weight:600;
}

.page-about .timeband{
  padding:clamp(18px,2.4vw,26px);
  background:var(--ink);
  color:var(--paper);
  border-left:3px solid var(--signal);
}
.page-about .timeband__head{
  display:flex;
  flex-wrap:wrap;
  align-items:baseline;
  justify-content:space-between;
  gap:8px 18px;
}
.page-about .timeband__label{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:var(--steel);
  margin:0;
}
.page-about .timeband__range{
  margin:0;
  font-family:var(--font-mono);
  font-size:clamp(18px,2.4vw,24px);
  color:var(--ember);
  letter-spacing:.02em;
}
.page-about .timeband__dash{
  padding:0 8px;
  color:var(--steel);
}
.page-about .timeband__bar{
  position:relative;
  height:6px;
  margin:14px 0 12px;
  background:rgba(199,208,202,.20);
  overflow:hidden;
}
.page-about .timeband__fill{
  position:absolute;
  inset:0;
  background:linear-gradient(90deg,var(--signal),var(--ember));
}
.page-about .timeband__note{
  font-size:14px;
  line-height:1.8;
  color:rgba(245,240,228,.78);
  margin:0;
}

/* ---------- 阶段轴 ---------- */
.page-about .arc{
  position:relative;
}
.page-about .arc__rail{
  display:none;
}
.page-about .arc__list{
  display:grid;
  gap:clamp(16px,2.2vw,22px);
  margin:0;
  padding:0;
  list-style:none;
}
.page-about .arc__item{
  position:relative;
  padding:clamp(16px,2.2vw,22px) clamp(16px,2.2vw,22px) clamp(16px,2.2vw,22px) clamp(20px,2.6vw,26px);
  background:rgba(199,208,202,.14);
  border:1px solid var(--about-paper-line);
  transition:transform var(--dur-base) var(--ease),border-color var(--dur-base) var(--ease),background-color var(--dur-base) var(--ease);
}
.page-about .arc__item::before{
  content:"";
  position:absolute;
  left:0;
  top:0;
  bottom:0;
  width:3px;
  background:var(--steel);
  transition:background-color var(--dur-base) var(--ease);
}
.page-about .arc__item:hover,
.page-about .arc__item:focus-within{
  transform:translateY(-3px);
  border-color:var(--signal);
  background:rgba(255,158,94,.14);
}
.page-about .arc__item:hover::before,
.page-about .arc__item:focus-within::before{
  background:var(--signal);
}
.page-about .arc__node{
  display:none;
}
.page-about .arc__year{
  display:block;
  font-family:var(--font-mono);
  font-size:13px;
  letter-spacing:.10em;
  color:var(--clay);
  margin:0 0 6px;
}
.page-about .arc__title{
  font-family:var(--font-body);
  font-size:17px;
  font-weight:700;
  line-height:1.5;
  margin:0 0 8px;
  color:var(--ink);
}
.page-about .arc__desc{
  font-size:14.5px;
  line-height:1.82;
  color:var(--slate);
  margin:0;
}
.page-about .arc__desc .num{
  color:var(--moss);
  font-weight:600;
}
.page-about .arc__desc .inline-link{
  color:var(--moss);
}

/* ---------- 覆盖数据带 ---------- */
.page-about .chapter--band{
  border-top:0;
  background:
    radial-gradient(80% 120% at 100% 0%,rgba(46,91,71,.85),rgba(8,37,31,0) 64%),
    var(--ink);
  color:var(--paper);
  padding-inline:clamp(16px,3.4vw,30px);
  margin-block:clamp(16px,2.4vw,26px);
}
.page-about .chapter--band .chapter__no{
  color:var(--ember);
}
.page-about .chapter--band .chapter__title{
  color:var(--paper);
}
.page-about .chapter__intro--onDark{
  color:rgba(245,240,228,.80);
  border-left-color:var(--signal);
}
.page-about .stats{
  display:grid;
  gap:0;
  margin:0;
  padding:0;
  list-style:none;
  border-top:1px solid var(--about-dark-line);
}
.page-about .stats__item{
  padding:clamp(16px,2.2vw,24px) 0;
  border-bottom:1px solid var(--about-dark-line);
}
.page-about .stats__num{
  font-family:var(--font-mono);
  font-size:clamp(30px,5vw,46px);
  font-weight:600;
  line-height:1;
  color:var(--ember);
  margin:0 0 8px;
}
.page-about .stats__unit{
  font-size:.52em;
  margin-left:2px;
  color:var(--steel);
}
.page-about .stats__label{
  font-size:14px;
  font-weight:600;
  letter-spacing:.04em;
  color:var(--paper);
  margin:0 0 4px;
}
.page-about .stats__desc{
  font-size:13.5px;
  line-height:1.72;
  color:rgba(199,208,202,.82);
  margin:0;
}

/* ---------- 工作方法 ---------- */
.page-about .steps{
  display:grid;
  gap:10px;
  margin-bottom:clamp(4px,1vw,10px);
}
.page-about .step-card{
  border:1px solid var(--about-paper-line);
  background:var(--paper);
  transition:border-color var(--dur-fast) var(--ease);
}
.page-about .step-card[open]{
  border-color:var(--about-paper-line-strong);
  background:rgba(199,208,202,.16);
}
.page-about .step-card__summary{
  display:flex;
  align-items:center;
  gap:12px;
  padding:14px clamp(14px,2vw,18px);
  cursor:pointer;
  list-style:none;
}
.page-about .step-card__summary::-webkit-details-marker{
  display:none;
}
.page-about .step-card__summary:hover,
.page-about .step-card__summary:focus-visible{
  outline:none;
  background:var(--signal-wash);
}
.page-about .step-card__summary:focus-visible{
  box-shadow:inset 0 0 0 2px rgba(255,90,31,.45);
}
.page-about .step-card__no{
  flex:none;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.08em;
  color:var(--clay);
}
.page-about .step-card__label{
  font-size:16px;
  font-weight:700;
  color:var(--ink);
  letter-spacing:.02em;
}
.page-about .step-card__hint{
  margin-left:auto;
  flex:none;
  width:10px;
  height:10px;
  border-right:2px solid var(--slate);
  border-bottom:2px solid var(--slate);
  transform:rotate(45deg) translateY(-2px);
  transition:transform var(--dur-base) var(--ease),border-color var(--dur-fast) var(--ease);
}
.page-about .step-card[open] .step-card__hint{
  transform:rotate(-135deg) translateY(-2px);
  border-color:var(--signal);
}
.page-about .step-card__body{
  padding:0 clamp(14px,2vw,18px) 16px;
}
.page-about .step-card__body p{
  font-size:15px;
  line-height:1.85;
  color:var(--about-body);
  margin:0;
}

/* ---------- 合作 ---------- */
.page-about .chapter--partner{
  padding-bottom:0;
}
.page-about .partner{
  display:grid;
  gap:clamp(18px,2.6vw,28px);
  align-items:start;
}
.page-about .partner__text p{
  font-size:17px;
  line-height:1.88;
  color:var(--about-body);
  margin:0 0 1em;
}
.page-about .partner__cta{
  margin-top:6px;
}
.page-about .partner__card{
  padding:clamp(18px,2.6vw,26px);
  background:var(--moss-wash);
  border:1px solid var(--about-paper-line);
  border-top:2px solid var(--signal);
}
.page-about .partner__card-label{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:var(--slate);
  margin:0 0 12px;
}
.page-about .partner__line{
  display:flex;
  flex-wrap:wrap;
  gap:4px 12px;
  font-size:14.5px;
  line-height:1.7;
  color:var(--ink);
  margin:0 0 10px;
  padding-bottom:10px;
  border-bottom:1px solid var(--about-paper-line);
}
.page-about .partner__key{
  flex:none;
  min-width:44px;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.08em;
  color:var(--clay);
}
.page-about .partner__note{
  font-size:13px;
  line-height:1.75;
  color:var(--slate);
  margin:0;
  padding-top:2px;
}

/* ---------- 响应式 ---------- */
@media (min-width:620px){
  .page-about .crew{
    grid-template-columns:repeat(2,minmax(0,1fr));
  }
  .page-about .stats{
    grid-template-columns:repeat(2,minmax(0,1fr));
    column-gap:clamp(20px,3vw,34px);
  }
  .page-about .arc__list{
    grid-template-columns:repeat(2,minmax(0,1fr));
  }
}

@media (min-width:900px){
  .page-about .hero__grid{
    grid-template-columns:minmax(0,7fr) minmax(0,5fr);
    align-items:end;
    gap:clamp(32px,4.5vw,64px);
  }
  .page-about .partner{
    grid-template-columns:minmax(0,7fr) minmax(0,5fr);
    gap:clamp(28px,4vw,52px);
  }
}

@media (min-width:1000px){
  .page-about .dossier__grid{
    grid-template-columns:180px minmax(0,1fr);
    gap:clamp(32px,4vw,64px);
    align-items:start;
  }
  .page-about .dossier__index{
    position:sticky;
    top:96px;
  }
  .page-about .dossier__index ol{
    display:block;
    overflow:visible;
    padding-bottom:0;
  }
  .page-about .dossier__index li + li{
    margin-top:6px;
  }
  .page-about .index-link{
    width:100%;
    white-space:normal;
  }
  .page-about .arc__rail{
    display:block;
    position:absolute;
    left:0;
    right:0;
    top:14px;
    width:100%;
    height:6px;
    overflow:visible;
  }
  .page-about .arc__list{
    grid-template-columns:repeat(4,minmax(0,1fr));
    gap:clamp(16px,2vw,26px);
    padding-top:calc(30px + clamp(16px,2.2vw,22px));
  }
  .page-about .arc__item{
    padding-top:clamp(18px,2.2vw,24px);
  }
  .page-about .arc__item::before{
    display:none;
  }
  .page-about .arc__node{
    display:block;
    position:absolute;
    top:calc(-1 * (30px + clamp(16px,2.2vw,22px)) - 5px);
    left:50%;
    width:11px;
    height:11px;
    margin-left:-5.5px;
    border-radius:50%;
    background:var(--steel);
    box-shadow:0 0 0 4px var(--paper);
    transition:background-color var(--dur-base) var(--ease),box-shadow var(--dur-base) var(--ease);
  }
  .page-about .arc__node--clay{
    background:var(--clay);
  }
  .page-about .arc__node--signal{
    background:var(--signal);
  }
  .page-about .arc__item:hover .arc__node,
  .page-about .arc__item:focus-within .arc__node{
    background:var(--signal);
    box-shadow:0 0 0 4px var(--paper),0 0 0 7px rgba(255,90,31,.26);
  }
  .page-about .stats{
    grid-template-columns:repeat(4,minmax(0,1fr));
  }
  .page-about .stats__item{
    padding-right:clamp(12px,1.8vw,22px);
  }
  .page-about .chapter--band{
    margin-inline:0;
  }
}

@media (min-width:1180px){
  .page-about .chapter__head{
    gap:26px;
  }
}

@media (prefers-reduced-motion:reduce){
  .page-about .arc__item,
  .page-about .arc__node,
  .page-about .step-card__hint,
  .page-about .index-link{
    transition:none;
  }
  .page-about .arc__item:hover,
  .page-about .arc__item:focus-within{
    transform:none;
  }
}
</main>