.page-about{
  --about-text:#C3CBE8;
  --about-cut:12px;
  color:var(--white);
  background:var(--ink-950);
  font-family:var(--sans);
  padding-bottom:56px;
  overflow-x:hidden;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero{
  position:relative;
  padding:28px 0 40px;
  background:
    radial-gradient(120% 130% at 10% -20%, #1B2A5E 0%, rgba(10,18,48,0) 62%),
    var(--ink-950);
  border-bottom:1px solid var(--line);
  overflow:hidden;
}
.page-about .about-hero::after{
  content:"";
  position:absolute;
  left:0;right:0;bottom:0;
  height:1px;
  background:repeating-linear-gradient(90deg,var(--line) 0 10px,transparent 10px 22px);
  opacity:.7;
}
.page-about .breadcrumb__list{
  display:flex;
  flex-wrap:wrap;
  gap:6px;
  list-style:none;
  margin:0 0 18px;
  padding:0;
  font-size:12px;
  color:var(--muted);
}
.page-about .breadcrumb__list a{
  color:var(--muted);
  text-decoration:none;
}
.page-about .breadcrumb__list a:hover,
.page-about .breadcrumb__list a:focus-visible{
  color:var(--cyan);
}
.page-about .breadcrumb__list li + li::before{
  content:"/";
  margin-right:6px;
  color:var(--line);
}
.page-about .eyebrow{
  margin:0 0 14px;
  font-size:11px;
  letter-spacing:.22em;
  text-transform:uppercase;
  color:var(--cyan);
}
.page-about .page-title{
  margin:0;
  font-size:clamp(28px,7.2vw,60px);
  line-height:1.14;
  font-weight:700;
  letter-spacing:-.01em;
}
.page-about .lede{
  margin:18px 0 0;
  max-width:640px;
  font-size:16px;
  line-height:1.9;
  color:var(--about-text);
}
.page-about .about-facts{
  display:grid;
  gap:1px;
  grid-template-columns:1fr;
  margin:28px 0 0;
  padding:0;
  list-style:none;
  background:var(--line);
  border:1px solid var(--line);
  clip-path:polygon(0 0,100% 0,100% calc(100% - var(--about-cut)),calc(100% - var(--about-cut)) 100%,0 100%);
}
.page-about .about-fact{
  display:flex;
  align-items:baseline;
  gap:14px;
  padding:14px 16px;
  background:var(--ink-900);
}
.page-about .about-fact__num{
  font-size:26px;
  line-height:1;
  color:var(--cyan);
  letter-spacing:-.02em;
}
.page-about .about-fact__label{
  font-size:13px;
  line-height:1.7;
  color:var(--muted);
}

/* ---------- 双栏骨架 ---------- */
.page-about .about-layout{
  padding-top:8px;
}
.page-about .about-index{
  border-bottom:1px solid var(--line);
  padding:16px 0 12px;
  margin-bottom:8px;
}
.page-about .about-index__title{
  margin:0 0 10px;
  font-size:10px;
  letter-spacing:.28em;
  color:var(--muted);
}
.page-about .about-index__list{
  display:flex;
  gap:8px;
  margin:0;
  padding:0 0 6px;
  list-style:none;
  overflow-x:auto;
  scrollbar-width:thin;
}
.page-about .about-index__link{
  display:flex;
  align-items:center;
  gap:8px;
  min-height:44px;
  padding:6px 12px;
  border:1px solid var(--line);
  background:var(--ink-900);
  color:var(--muted);
  font-size:13px;
  white-space:nowrap;
  text-decoration:none;
  transition:color .24s var(--ease),border-color .24s var(--ease),background .24s var(--ease);
}
.page-about .about-index__num{
  font-size:11px;
  letter-spacing:.12em;
  color:var(--violet);
}
.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible{
  color:var(--white);
  border-color:var(--violet);
}
.page-about .about-index__link[aria-current="true"],
.page-about .about-index__link[data-active="true"]{
  color:var(--white);
  border-color:var(--violet);
  background:var(--ink-800);
}

/* ---------- 章节 ---------- */
.page-about .about-section{
  padding:36px 0 8px;
  border-top:1px solid var(--line);
}
.page-about .about-section:first-child{
  border-top:0;
  padding-top:24px;
}
.page-about .sec-head{
  display:flex;
  align-items:center;
  gap:12px;
  margin-bottom:18px;
}
.page-about .sec-num{
  flex:0 0 auto;
  padding:3px 9px;
  font-size:11px;
  letter-spacing:.12em;
  color:var(--cyan);
  border:1px solid var(--line);
  background:var(--ink-900);
  clip-path:polygon(0 0,calc(100% - 5px) 0,100% 5px,100% 100%,0 100%);
}
.page-about .sec-title{
  margin:0;
  font-size:clamp(21px,4.6vw,30px);
  line-height:1.3;
  font-weight:700;
}
.page-about .sec-lead{
  margin:0 0 18px;
  padding-left:14px;
  border-left:3px solid var(--cyan);
  font-size:16px;
  line-height:1.8;
  font-weight:700;
  color:var(--white);
}
.page-about .body-text{
  margin:0 0 14px;
  font-size:15px;
  line-height:1.95;
  color:var(--about-text);
}
.page-about .inline-link{
  color:var(--cyan);
  text-decoration:none;
  border-bottom:1px solid rgba(34,211,238,.45);
}
.page-about .inline-link:hover,
.page-about .inline-link:focus-visible{
  border-bottom-color:var(--cyan);
}

/* ---------- 清单 ---------- */
.page-about .scope-list{
  margin:20px 0 8px;
  padding:0;
  list-style:none;
  border-top:1px solid var(--line);
}
.page-about .scope-list li{
  display:grid;
  grid-template-columns:1fr;
  gap:4px;
  padding:12px 0;
  border-bottom:1px solid var(--line);
}
.page-about .scope-list__k{
  font-size:11px;
  letter-spacing:.14em;
  color:var(--orange);
}
.page-about .scope-list__v{
  font-size:14px;
  line-height:1.8;
  color:var(--about-text);
}

/* ---------- 部门分区 ---------- */
.page-about .dept-grid{
  display:grid;
  grid-template-columns:repeat(2,minmax(0,1fr));
  gap:10px;
  margin:24px 0 24px;
  padding:0;
  list-style:none;
}
.page-about .dept{
  position:relative;
  padding:14px 12px 16px 15px;
  background:var(--ink-800);
  border-left:3px solid var(--line);
  clip-path:polygon(0 0,100% 0,100% calc(100% - 10px),calc(100% - 10px) 100%,0 100%);
  transition:border-color .24s var(--ease),background .24s var(--ease),transform .24s var(--ease);
}
.page-about .dept:hover,
.page-about .dept:focus-within{
  border-left-width:6px;
  background:var(--ink-900);
  transform:translateY(-2px);
}
.page-about .dept__name{
  display:block;
  font-size:15px;
  font-weight:700;
  color:var(--white);
}
.page-about .dept__duty{
  display:block;
  margin-top:4px;
  font-size:11px;
  letter-spacing:.1em;
  color:var(--muted);
}
.page-about .dept__note{
  margin:8px 0 0;
  font-size:12px;
  line-height:1.7;
  color:var(--muted);
  opacity:.85;
  transition:opacity .24s var(--ease);
}
.page-about .dept:hover .dept__note,
.page-about .dept:focus-within .dept__note{
  opacity:1;
  color:var(--about-text);
}
.page-about .dept--product{border-left-color:var(--violet);}
.page-about .dept--dev{border-left-color:var(--cyan);}
.page-about .dept--doc{border-left-color:var(--orange);}
.page-about .dept--support{border-left-color:var(--green);}
.page-about .dept--qa{border-left-color:var(--amber);}

/* ---------- 图 ---------- */
.page-about .about-figure{
  margin:22px 0 0;
  border:1px solid var(--line);
  background:linear-gradient(160deg,var(--ink-800),var(--ink-900));
  clip-path:polygon(0 0,100% 0,100% calc(100% - 16px),calc(100% - 16px) 100%,0 100%);
  overflow:hidden;
}
.page-about .about-figure img{
  display:block;
  width:100%;
  max-width:100%;
  height:auto;
  object-fit:cover;
}
.page-about .about-figure .media-frame__caption{
  padding:10px 14px 12px;
  font-size:12px;
  line-height:1.7;
  color:var(--muted);
  border-top:1px solid var(--line);
}

/* ---------- 服务 ---------- */
.page-about .service-grid{
  display:grid;
  gap:18px;
}
.page-about .service-metrics{
  display:grid;
  gap:1px;
  grid-template-columns:1fr;
  margin:20px 0 0;
  padding:0;
  background:var(--line);
  border:1px solid var(--line);
}
.page-about .service-metric{
  display:flex;
  align-items:baseline;
  gap:12px;
  padding:12px 14px;
  background:var(--ink-900);
}
.page-about .service-metric dt{
  flex:0 0 auto;
  font-size:14px;
  color:var(--green);
  letter-spacing:.02em;
}
.page-about .service-metric dd{
  margin:0;
  font-size:13px;
  line-height:1.7;
  color:var(--muted);
}

/* ---------- 时间轴 ---------- */
.page-about .timeline{
  display:flex;
  gap:0;
  margin:22px 0 0;
  padding:8px 0 14px;
  list-style:none;
  overflow-x:auto;
  scroll-snap-type:x proximity;
}
.page-about .timeline__item{
  position:relative;
  flex:0 0 250px;
  padding:0 16px 0 0;
  scroll-snap-align:start;
}
.page-about .timeline__item::before{
  content:"";
  position:absolute;
  top:9px;
  left:18px;
  right:0;
  border-top:2px dotted var(--line);
}
.page-about .timeline__dot{
  position:relative;
  display:block;
  width:18px;
  height:18px;
  margin-bottom:14px;
  background:var(--ink-900);
  border:2px solid var(--muted);
  clip-path:polygon(0 0,calc(100% - 6px) 0,100% 6px,100% 100%,6px 100%,0 calc(100% - 6px));
  transition:background .24s var(--ease),border-color .24s var(--ease),transform .24s var(--ease);
}
.page-about .timeline__item--v3 .timeline__dot{border-color:var(--muted);}
.page-about .timeline__item--v4 .timeline__dot{border-color:var(--orange);}
.page-about .timeline__item--now .timeline__dot{border-color:var(--cyan);}
.page-about .timeline__item:hover .timeline__dot{
  background:var(--orange);
  border-color:var(--orange);
  transform:scale(1.1);
}
.page-about .timeline__item--now:hover .timeline__dot{
  background:var(--cyan);
  border-color:var(--cyan);
}
.page-about .timeline__stage{
  margin:0 0 6px;
  font-size:11px;
  letter-spacing:.14em;
  color:var(--muted);
}
.page-about .timeline__item--v4 .timeline__stage,
.page-about .timeline__item--now .timeline__stage{
  color:var(--orange);
}
.page-about .timeline__title{
  margin:0 0 6px;
  font-size:16px;
  font-weight:700;
  color:var(--white);
}
.page-about .timeline__text{
  margin:0;
  padding-right:8px;
  font-size:13px;
  line-height:1.8;
  color:var(--about-text);
}

/* ---------- 收尾 ---------- */
.page-about .about-cta{
  margin:26px 0 0;
  padding:20px 18px;
  background:linear-gradient(120deg,var(--ink-800),var(--ink-900) 70%);
  border:1px solid var(--line);
  border-left:4px solid var(--cyan);
  clip-path:polygon(0 0,100% 0,100% calc(100% - 16px),calc(100% - 16px) 100%,0 100%);
}
.page-about .about-cta__text{
  margin:0 0 16px;
  font-size:15px;
  line-height:1.85;
  color:var(--white);
}
.page-about .about-cta__actions{
  display:flex;
  flex-wrap:wrap;
  gap:10px;
}
.page-about .about-cta__actions .btn{
  min-height:44px;
  display:inline-flex;
  align-items:center;
  text-decoration:none;
}

/* ---------- 平板 ---------- */
@media (min-width:680px){
  .page-about .about-facts{grid-template-columns:repeat(3,minmax(0,1fr));}
  .page-about .about-fact{flex-direction:column;align-items:flex-start;gap:8px;}
  .page-about .scope-list li{grid-template-columns:130px minmax(0,1fr);gap:14px;align-items:baseline;}
  .page-about .dept-grid{grid-template-columns:repeat(3,minmax(0,1fr));}
  .page-about .service-metrics{grid-template-columns:repeat(3,minmax(0,1fr));}
  .page-about .service-metric{flex-direction:column;align-items:flex-start;gap:6px;}
  .page-about .timeline__item{flex:0 0 270px;}
}

/* ---------- 桌面：编辑部式双栏 + 横向时间轴 ---------- */
@media (min-width:960px){
  .page-about{padding-bottom:80px;}
  .page-about .about-hero{padding:40px 0 52px;}
  .page-about .lede{max-width:660px;}
  .page-about .about-layout{
    display:grid;
    grid-template-columns:168px minmax(0,1fr);
    column-gap:48px;
    align-items:start;
    padding-top:24px;
  }
  .page-about .about-index{
    position:sticky;
    top:96px;
    border-bottom:0;
    border-left:1px solid var(--line);
    padding:0 0 0 14px;
    margin:0;
  }
  .page-about .about-index__list{
    flex-direction:column;
    gap:2px;
    overflow:visible;
    padding:0;
  }
  .page-about .about-index__link{
    align-items:flex-start;
    gap:10px;
    border:0;
    background:transparent;
    padding:10px 8px 10px 0;
    white-space:normal;
  }
  .page-about .about-index__link:hover,
  .page-about .about-index__link:focus-visible{
    border:0;
    background:transparent;
    color:var(--white);
  }
  .page-about .about-index__link[aria-current="true"],
  .page-about .about-index__link[data-active="true"]{
    background:transparent;
    border:0;
    color:var(--cyan);
  }
  .page-about .about-index__num{
    writing-mode:vertical-rl;
    text-orientation:mixed;
    letter-spacing:.24em;
    font-size:12px;
    padding-top:2px;
  }
  .page-about .about-index__label{
    font-size:13px;
    line-height:1.5;
    padding-top:2px;
  }
  .page-about .about-section{padding:48px 0 12px;}
  .page-about .sec-head{margin-bottom:22px;}
  .page-about .body-text{max-width:720px;}
  .page-about .dept-grid{
    grid-template-columns:repeat(12,minmax(0,1fr));
    gap:12px;
  }
  .page-about .dept:nth-child(1){grid-column:span 3;}
  .page-about .dept:nth-child(2){grid-column:span 3;}
  .page-about .dept:nth-child(3){grid-column:span 2;}
  .page-about .dept:nth-child(4){grid-column:span 2;}
  .page-about .dept:nth-child(5){grid-column:span 2;}
  .page-about .service-grid{
    grid-template-columns:minmax(0,1fr) 320px;
    column-gap:32px;
    align-items:start;
  }
  .page-about .about-figure--side{margin-top:2px;}
  .page-about .timeline{
    overflow:visible;
    padding-top:12px;
  }
  .page-about .timeline__item{
    flex:1 1 0;
    min-width:0;
    padding-right:20px;
  }
  .page-about .about-cta{
    display:flex;
    align-items:center;
    justify-content:space-between;
    gap:24px;
    padding:24px 26px;
  }
  .page-about .about-cta__text{margin:0;max-width:520px;}
}

@media (prefers-reduced-motion:reduce){
  .page-about .dept,
  .page-about .timeline__dot,
  .page-about .about-index__link,
  .page-about .dept__note{
    transition:none;
  }
  .page-about .dept:hover,
  .page-about .dept:focus-within,
  .page-about .timeline__item:hover .timeline__dot{
    transform:none;
  }
}
</main>