.page-about{
  --ab-rail:176px;
  --ab-pad:clamp(16px,3.2vw,34px);
  background:var(--ink);
  color:var(--white);
  font-family:var(--font-body);
  overflow-x:clip;
}
.page-about img{max-width:100%;height:auto;display:block;}
.page-about p{font-size:15px;line-height:1.78;color:var(--muted);margin:0 0 16px;}
.page-about p:last-child{margin-bottom:0;}
.page-about p strong{color:var(--white);font-weight:600;}
.page-about h2,.page-about h3{font-family:var(--font-display);color:var(--white);}
.page-about a{color:var(--white);}
.page-about a:focus-visible,
.page-about [tabindex="0"]:focus-visible{outline:2px solid var(--signal);outline-offset:3px;}

.page-about .ab-key{
  font-family:var(--font-mono);
  color:var(--white);
  border-bottom:2px solid var(--signal);
  padding-bottom:1px;
  white-space:nowrap;
}
.page-about .ab-key--blue{border-bottom-color:var(--blue);}

/* ---------- 顶部信息条 ---------- */
.page-about .ab-topline{
  display:flex;
  flex-wrap:wrap;
  gap:8px 20px;
  align-items:center;
  justify-content:space-between;
  padding-top:14px;
  padding-bottom:14px;
  border-bottom:1px solid var(--line);
}
.page-about .ab-stamp{
  margin:0;
  font-size:12px;
  letter-spacing:.12em;
  color:var(--muted);
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero{padding-top:clamp(26px,5vw,56px);}
.page-about .ab-hero-inner{position:relative;}
.page-about .ab-kicker{
  margin:0 0 14px;
  font-size:12px;
  letter-spacing:.28em;
  color:var(--signal);
}
.page-about h1{
  font-family:var(--font-display);
  font-weight:900;
  font-size:clamp(30px,8vw,60px);
  line-height:1.04;
  letter-spacing:-.02em;
  margin:0 0 18px;
  max-width:22ch;
}
.page-about .ab-lead{
  font-size:clamp(15px,2.3vw,18px);
  line-height:1.7;
  color:var(--muted);
  max-width:64ch;
}
.page-about .ab-hero-meta{
  list-style:none;
  display:grid;
  grid-template-columns:repeat(2,minmax(0,1fr));
  gap:1px;
  margin:clamp(24px,4vw,40px) 0 0;
  padding:1px;
  background:var(--line);
  border:2px solid var(--line);
}
.page-about .ab-hero-meta li{
  background:var(--panel);
  padding:14px 14px 12px;
  display:flex;
  flex-direction:column;
  gap:6px;
  min-width:0;
}
.page-about .ab-meta-num{
  font-size:clamp(15px,2.6vw,19px);
  color:var(--signal);
  letter-spacing:-.01em;
  font-variant-numeric:tabular-nums;
}
.page-about .ab-hero-meta li:nth-child(2) .ab-meta-num{color:var(--white);}
.page-about .ab-hero-meta li:nth-child(3) .ab-meta-num{color:var(--blue);}
.page-about .ab-hero-meta li:nth-child(4) .ab-meta-num{color:var(--warm);}
.page-about .ab-meta-label{
  font-size:12px;
  letter-spacing:.1em;
  color:var(--muted);
}
.page-about .ab-hero-figure{margin:clamp(26px,4vw,46px) auto 0;}
.page-about .ab-hero-figure img{aspect-ratio:16/9;object-fit:cover;width:100%;}

/* ---------- 主体骨架 ---------- */
.page-about .ab-shell{
  display:grid;
  gap:clamp(18px,3vw,40px);
  padding-top:clamp(30px,5vw,66px);
  padding-bottom:clamp(30px,5vw,66px);
}
.page-about .ab-flow{min-width:0;}

/* 章节侧栏 */
.page-about .ab-rail{display:none;}
.page-about .ab-rail-title{
  margin:0 0 12px;
  font-size:11px;
  letter-spacing:.3em;
  color:var(--muted);
}
.page-about .ab-rail-list{
  list-style:none;
  margin:0;
  padding:0;
  border-left:2px solid var(--line);
}
.page-about .ab-rail-link{
  display:flex;
  align-items:baseline;
  gap:10px;
  padding:9px 12px;
  text-decoration:none;
  color:var(--muted);
  font-size:13px;
  line-height:1.4;
  border-left:2px solid transparent;
  margin-left:-2px;
  transition:color .2s ease,border-color .2s ease,background-color .2s ease;
}
.page-about .ab-rail-num{
  font-size:11px;
  color:var(--line);
  transition:color .2s ease;
}
.page-about .ab-rail-link:hover,
.page-about .ab-rail-link:focus-visible{
  color:var(--white);
  background:var(--panel);
  border-left-color:var(--signal);
}
.page-about .ab-rail-link:hover .ab-rail-num,
.page-about .ab-rail-link:focus-visible .ab-rail-num{color:var(--signal);}

/* ---------- 章节通用 ---------- */
.page-about .ab-chapter{
  position:relative;
  padding:clamp(26px,4.4vw,48px) 0;
  border-top:1px solid var(--line);
}
.page-about .ab-chapter::before{
  content:"";
  display:block;
  width:72px;
  height:3px;
  margin-bottom:20px;
  background:var(--signal);
}
.page-about .ab-chapter--perf::before{background:var(--blue);}
.page-about .ab-chapter--process::before{background:var(--signal);}
.page-about .ab-chapter--blue::before{background:var(--blue);}
.page-about .ab-chapter--warm::before{background:var(--warm);}
.page-about .ab-chapter-head{
  display:flex;
  gap:12px;
  align-items:baseline;
  margin-bottom:16px;
}
.page-about .ab-chapter-num{
  flex:none;
  font-size:11px;
  letter-spacing:.08em;
  color:var(--signal);
  border:1px solid var(--line);
  padding:3px 7px;
}
.page-about .ab-chapter h2{
  margin:0;
  font-weight:900;
  font-size:clamp(21px,4.4vw,34px);
  line-height:1.18;
  letter-spacing:-.01em;
}
.page-about .axis-band{margin:0 0 18px;}

/* ---------- 团队矩阵 ---------- */
.page-about .ab-matrix{
  display:grid;
  gap:1px;
  margin:22px 0 0;
  background:var(--line);
  border:2px solid var(--line);
  box-shadow:var(--shadow-hard);
}
.page-about .ab-cell{
  background:var(--panel);
  padding:18px 16px;
  min-width:0;
  transition:background-color .2s ease,transform .2s ease;
}
.page-about .ab-cell-role{
  display:block;
  font-size:11px;
  letter-spacing:.22em;
  color:var(--signal);
  margin-bottom:8px;
}
.page-about .ab-cell h3{
  margin:0 0 8px;
  font-size:17px;
  font-weight:800;
  letter-spacing:-.01em;
}
.page-about .ab-cell p{font-size:14px;line-height:1.7;margin:0;}
.page-about .ab-cell-more{
  margin-top:8px;
  max-height:none;
  opacity:1;
  color:var(--muted);
}
.page-about .ab-cell:hover{background:#1b2c26;}
.page-about .ab-cell:hover .ab-cell-more,
.page-about .ab-cell:focus-within .ab-cell-more{color:var(--white);}
.page-about .ab-review{
  margin-top:20px;
  padding-left:16px;
  border-left:3px solid var(--signal);
}

/* ---------- 图片块 ---------- */
.page-about .ab-figure{
  margin:clamp(24px,4vw,42px) 0 0;
  max-width:860px;
}
.page-about .ab-figure--version{max-width:720px;}
.page-about .ab-figure--team img{aspect-ratio:14/9;object-fit:cover;width:100%;}
.page-about .ab-figure--version img{aspect-ratio:3/2;object-fit:cover;width:100%;}

/* ---------- 版本阶梯 ---------- */
.page-about .ab-steps{margin-top:22px;}
.page-about .ab-steps-svg{
  width:100%;
  height:auto;
  display:block;
  margin-bottom:18px;
}
.page-about .ab-step-track{fill:none;stroke:var(--line);stroke-width:2;}
.page-about .ab-step-line{fill:none;stroke:var(--signal);stroke-width:2;}
.page-about .ab-dot{stroke:none;}
.page-about .ab-dot--blue{fill:var(--blue);}
.page-about .ab-dot--signal{fill:var(--signal);}
.page-about .ab-dot--warm{fill:var(--warm);}
.page-about .ab-step-list{
  list-style:none;
  display:grid;
  gap:14px;
  margin:0;
  padding:0;
}
.page-about .ab-step{
  background:var(--panel);
  border:2px solid var(--line);
  padding:18px 16px;
  box-shadow:var(--shadow-hard);
  transition:transform .2s ease,box-shadow .2s ease,border-color .2s ease;
}
.page-about .ab-step:hover,
.page-about .ab-step:focus-within{
  transform:translateY(-2px);
  box-shadow:var(--shadow-lift);
  border-color:var(--signal);
}
.page-about .ab-step-ver{
  display:inline-block;
  font-size:19px;
  color:var(--signal);
  border-bottom:2px solid var(--line);
  padding-bottom:2px;
  margin-bottom:10px;
  font-variant-numeric:tabular-nums;
}
.page-about .ab-step:nth-child(2) .ab-step-ver{color:var(--blue);}
.page-about .ab-step:nth-child(3) .ab-step-ver{color:var(--warm);}
.page-about .ab-step h3{
  margin:0 0 8px;
  font-size:17px;
  font-weight:800;
}
.page-about .ab-step p{font-size:14px;line-height:1.7;margin:0;}

/* ---------- 延伸入口 ---------- */
.page-about .ab-next{
  margin-top:clamp(28px,4.6vw,52px);
  padding-top:clamp(22px,3.4vw,34px);
  border-top:2px solid var(--line);
}
.page-about .ab-next-title{
  margin:0 0 16px;
  font-size:13px;
  letter-spacing:.24em;
  font-weight:700;
  color:var(--muted);
}
.page-about .ab-next-list{
  list-style:none;
  display:grid;
  gap:12px;
  margin:0;
  padding:0;
}
.page-about .ab-next-link{
  display:block;
  padding:18px 16px;
  background:var(--panel);
  border:2px solid var(--line);
  text-decoration:none;
  transition:transform .2s ease,box-shadow .2s ease,border-color .2s ease;
}
.page-about .ab-next-link:hover,
.page-about .ab-next-link:focus-visible{
  transform:translateY(-2px);
  box-shadow:var(--shadow-hard);
  border-color:var(--signal);
}
.page-about .ab-next-num{
  display:block;
  font-size:12px;
  color:var(--signal);
  letter-spacing:.2em;
  margin-bottom:8px;
}
.page-about .ab-next-name{
  display:block;
  font-family:var(--font-display);
  font-weight:800;
  font-size:18px;
  color:var(--white);
  margin-bottom:6px;
}
.page-about .ab-next-desc{
  display:block;
  font-size:13px;
  line-height:1.65;
  color:var(--muted);
}
.page-about .ab-backlink-row{margin:22px 0 0;}
.page-about .ab-backlink{
  color:var(--signal);
  text-decoration:none;
  border-bottom:2px solid var(--line);
  padding-bottom:2px;
  font-size:14px;
  transition:border-color .2s ease;
}
.page-about .ab-backlink:hover,
.page-about .ab-backlink:focus-visible{border-bottom-color:var(--signal);}

/* ---------- 显现 ---------- */
.js-on .page-about [data-reveal]{
  opacity:0;
  transform:translateY(14px);
  transition:opacity .35s ease,transform .35s ease;
}
.js-on .page-about [data-reveal].is-in{
  opacity:1;
  transform:none;
}

/* ---------- 平板 ---------- */
@media (min-width:720px){
  .page-about .ab-hero-meta{grid-template-columns:repeat(4,minmax(0,1fr));}
  .page-about .ab-next-list{grid-template-columns:repeat(3,minmax(0,1fr));}
}

@media (min-width:820px){
  .page-about .ab-matrix{
    grid-template-columns:1.5fr 1fr 1fr;
    grid-template-areas:
      "a b c"
      "a d d";
  }
  .page-about .ab-cell--data{grid-area:a;}
  .page-about .ab-cell--tactics{grid-area:b;}
  .page-about .ab-cell--edit{grid-area:c;}
  .page-about .ab-cell--front{grid-area:d;}

  .page-about .ab-cell-more{
    max-height:0;
    opacity:0;
    margin-top:0;
    overflow:hidden;
    transition:max-height .2s ease,opacity .2s ease,margin-top .2s ease;
  }
  .page-about .ab-cell:hover .ab-cell-more,
  .page-about .ab-cell:focus-within .ab-cell-more{
    max-height:200px;
    opacity:1;
    margin-top:10px;
  }

  .page-about .ab-step-list{grid-template-columns:repeat(3,minmax(0,1fr));}
  .page-about .ab-steps-svg{margin-bottom:24px;}
}

/* ---------- 桌面 ---------- */
@media (min-width:960px){
  .page-about .ab-shell{
    grid-template-columns:var(--ab-rail) minmax(0,1fr);
    gap:clamp(28px,4vw,64px);
    align-items:start;
  }
  .page-about .ab-rail{
    display:block;
    position:sticky;
    top:calc(var(--header-h) + 28px);
    padding-top:6px;
  }
  .page-about .ab-lead{font-size:18px;}
  .page-about p{font-size:15.5px;}
}

/* ---------- 动效收敛 ---------- */
@media (prefers-reduced-motion:reduce){
  .page-about .ab-cell,
  .page-about .ab-step,
  .page-about .ab-next-link,
  .page-about .ab-rail-link{transition:none;}
  .page-about .ab-cell:hover,
  .page-about .ab-step:hover,
  .page-about .ab-next-link:hover{transform:none;}
  .js-on .page-about [data-reveal]{
    opacity:1;
    transform:none;
    transition:none;
  }
}
</main>