.page-about{
  --about-index-w:14rem;
  --about-pad:clamp(1.1rem,3vw,1.75rem);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero{
  position:relative;
  overflow:hidden;
  padding:clamp(1.25rem,3vw,2rem) 0 clamp(2.5rem,5vw,4rem);
  background:
    radial-gradient(120% 150% at 92% -20%, rgba(255,107,26,.22), transparent 56%),
    radial-gradient(90% 120% at -10% 110%, rgba(37,240,178,.12), transparent 60%),
    linear-gradient(155deg,#061826 0%,#0B2F33 58%,#061826 100%);
  border-bottom:1px solid var(--line);
}
.page-about .about-hero::after{
  content:"";
  position:absolute;
  top:-30%;
  right:-14%;
  width:min(42rem,72%);
  height:160%;
  background:linear-gradient(180deg,rgba(255,107,26,.16),rgba(37,240,178,0) 78%);
  transform:skewX(-14deg);
  pointer-events:none;
  z-index:0;
}
.page-about .about-hero > .container{
  position:relative;
  z-index:1;
}
.page-about .about-hero .breadcrumb{
  margin:0 0 clamp(.75rem,2vw,1.25rem);
}
.page-about .about-hero .breadcrumb-link{
  color:var(--slate);
  text-decoration:none;
}
.page-about .about-hero .breadcrumb-link:hover,
.page-about .about-hero .breadcrumb-link:focus-visible{
  color:var(--mist);
  text-decoration:underline;
}
.page-about .about-hero .breadcrumb-current{
  color:rgba(234,242,247,.9);
}

.page-about .about-hero-grid{
  display:grid;
  gap:clamp(1.5rem,4vw,3rem);
}
.page-about .about-hero .kicker{
  color:var(--mint);
}
.page-about .about-hero h1{
  margin:.45rem 0 0;
  font-family:var(--font-heading);
  font-weight:700;
  font-size:clamp(1.95rem,6vw,3.5rem);
  line-height:1.13;
  letter-spacing:-.01em;
  color:var(--mist);
  max-width:20ch;
}
.page-about .about-hl{
  color:var(--orange);
  box-shadow:inset 0 -.34em 0 rgba(255,107,26,.22);
}
.page-about .about-lede{
  margin:1.1rem 0 0;
  max-width:54ch;
  font-size:clamp(1rem,2.2vw,1.1rem);
  line-height:1.82;
  color:rgba(234,242,247,.8);
}
.page-about .about-hero-actions{
  display:flex;
  flex-wrap:wrap;
  gap:.7rem;
  margin-top:1.5rem;
}

.page-about .about-figures{
  display:grid;
  grid-template-columns:repeat(2,minmax(0,1fr));
  gap:.7rem;
}
.page-about .about-figure{
  padding:.85rem .95rem 1rem;
  border:1px solid var(--line);
  border-radius:var(--r-md);
  background:rgba(6,24,38,.55);
  transition:border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}
.page-about .about-figure:hover{
  border-color:var(--line-strong);
  transform:translateY(-2px);
}
.page-about .about-figure-num{
  display:block;
  font-family:var(--font-display);
  font-weight:800;
  font-size:clamp(1.7rem,5vw,2.35rem);
  line-height:1;
  letter-spacing:.01em;
  color:var(--mint);
}
.page-about .about-figure:nth-child(2) .about-figure-num{color:var(--orange);}
.page-about .about-figure:nth-child(3) .about-figure-num{color:var(--mist);}
.page-about .about-figure:nth-child(4) .about-figure-num{color:var(--gold);}
.page-about .about-figure-unit{
  font-size:.55em;
  margin-left:.12em;
}
.page-about .about-figure-label{
  display:block;
  margin-top:.45rem;
  font-family:var(--font-mono);
  font-size:.72rem;
  letter-spacing:.08em;
  color:var(--slate);
}

/* ---------- 主体骨架 ---------- */
.page-about .about-body{
  display:grid;
  gap:clamp(1.25rem,3vw,2.75rem);
  padding-block:clamp(2rem,5vw,3.75rem);
}

/* 章节目录 */
.page-about .about-index{
  border:1px solid var(--line-soft);
  border-radius:var(--r-md);
  background:var(--surface);
  padding:.85rem .9rem .9rem;
  overflow-x:auto;
  scrollbar-width:thin;
}
.page-about .about-index-title{
  margin:0 0 .55rem;
  font-family:var(--font-mono);
  font-size:.68rem;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--slate);
}
.page-about .about-index-list{
  display:flex;
  gap:.35rem;
  margin:0;
  padding:0;
  list-style:none;
}
.page-about .about-index-link{
  position:relative;
  display:block;
  white-space:nowrap;
  padding:.5rem .6rem .5rem 1.05rem;
  border-radius:var(--r-sm);
  font-size:.88rem;
  line-height:1.4;
  color:rgba(234,242,247,.72);
  text-decoration:none;
  transition:color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}
.page-about .about-index-link::before{
  content:"";
  position:absolute;
  left:.28rem;
  top:50%;
  width:.4rem;
  height:2px;
  background:var(--orange);
  opacity:.45;
  transform:translateY(-50%) scaleX(.7);
  transform-origin:left center;
  transition:opacity var(--dur) var(--ease), transform var(--dur) var(--ease);
}
.page-about .about-index-link:hover,
.page-about .about-index-link:focus-visible{
  color:var(--mist);
  background:var(--surface-2);
}
.page-about .about-index-link:hover::before,
.page-about .about-index-link:focus-visible::before{
  opacity:1;
  transform:translateY(-50%) scaleX(1);
}

/* 章节 */
.page-about .about-section{
  padding-block:clamp(1.5rem,4vw,2.4rem);
  scroll-margin-top:clamp(5rem,12vh,7rem);
}
.page-about .about-section:first-child{
  padding-top:0;
}
.page-about .about-section + .about-section{
  border-top:1px solid var(--line-soft);
}
.page-about .about-sec-head{
  display:flex;
  align-items:baseline;
  gap:.7rem;
  margin-bottom:1rem;
}
.page-about .about-sec-num{
  font-family:var(--font-mono);
  font-size:.72rem;
  letter-spacing:.16em;
  color:var(--orange);
}
.page-about .about-section h2{
  margin:0;
  font-family:var(--font-heading);
  font-weight:700;
  font-size:clamp(1.35rem,3.6vw,2rem);
  line-height:1.28;
  color:var(--mist);
}
.page-about .about-section p{
  margin:0 0 1rem;
  max-width:64ch;
  line-height:1.8;
  color:rgba(234,242,247,.78);
}
.page-about .about-section p:last-child{
  margin-bottom:0;
}

/* 图片 */
.page-about .about-figure-img,
.page-about .about-workbench,
.page-about .about-badges{
  margin:clamp(1.25rem,3vw,1.75rem) 0 0;
}
.page-about .media-frame img{
  display:block;
  width:100%;
  height:auto;
  max-width:100%;
  object-fit:cover;
  border-radius:var(--r-sm);
}

/* ---------- 版本时间轴 ---------- */
.page-about .about-versions{
  display:grid;
  gap:var(--gap);
  margin-top:1.35rem;
}
.page-about .about-version-list{
  display:flex;
  flex-direction:column;
  gap:.5rem;
  padding:0;
  border:0;
  background:none;
  overflow:visible;
}
.page-about .about-version-tab{
  --ver-accent:var(--slate);
  display:flex;
  align-items:baseline;
  gap:.7rem;
  width:100%;
  min-height:44px;
  padding:.7rem .9rem;
  text-align:left;
  border:1px solid var(--line);
  border-left:3px solid var(--ver-accent);
  border-radius:var(--r-sm);
  background:var(--surface);
  color:rgba(234,242,247,.76);
  font-family:var(--font-heading);
  font-size:.94rem;
  line-height:1.4;
  cursor:pointer;
  transition:background-color var(--dur) var(--ease), color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.page-about .about-version-tab.v1{--ver-accent:var(--slate);}
.page-about .about-version-tab.v2{--ver-accent:var(--gold);}
.page-about .about-version-tab.v3{--ver-accent:var(--mist);}
.page-about .about-version-tab.v4{--ver-accent:var(--orange);}
.page-about .about-version-year{
  font-family:var(--font-display);
  font-weight:800;
  font-size:1.3rem;
  line-height:1;
  letter-spacing:.02em;
  color:var(--ver-accent);
  flex:0 0 auto;
}
.page-about .about-version-name{
  flex:1 1 auto;
}
.page-about .about-version-tab:hover,
.page-about .about-version-tab:focus-visible{
  background:var(--surface-2);
  color:var(--mist);
}
.page-about .about-version-tab[aria-selected="true"]{
  background:var(--surface-2);
  border-color:var(--ver-accent);
  border-left-width:3px;
  color:var(--mist);
  box-shadow:inset 0 0 0 1px rgba(255,107,26,.1);
}
.page-about .about-version-panels{
  display:block;
}
.page-about .about-version-panel{
  display:block;
  margin:0;
  padding:var(--about-pad);
  border:1px solid var(--line);
  border-radius:var(--r-md);
  background:linear-gradient(150deg, rgba(35,27,77,.5), rgba(6,24,38,.55) 70%);
}
.page-about .about-version-panel[hidden]{
  display:none;
}
.page-about .about-version-panel h3{
  margin:0 0 .55rem;
  font-family:var(--font-heading);
  font-size:1.05rem;
  font-weight:600;
  color:var(--mist);
}
.page-about .about-version-panel p{
  margin:0 0 .7rem;
  max-width:none;
  font-size:.95rem;
  line-height:1.78;
  color:rgba(234,242,247,.76);
}
.page-about .about-version-note{
  margin:0;
  font-family:var(--font-mono);
  font-size:.74rem;
  letter-spacing:.05em;
  color:var(--slate);
}

/* ---------- 合作网络 ---------- */
.page-about .about-net{
  display:flex;
  flex-wrap:wrap;
  gap:.5rem;
  margin:1.25rem 0 0;
  padding:0;
  list-style:none;
}
.page-about .about-net li{
  padding:.45rem .8rem;
  border:1px solid var(--line);
  border-radius:999px;
  background:var(--surface);
  font-family:var(--font-mono);
  font-size:.76rem;
  letter-spacing:.04em;
  color:rgba(234,242,247,.8);
  transition:border-color var(--dur) var(--ease), color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}
.page-about .about-net li:nth-child(3n+1):hover{
  border-color:var(--orange);
  color:var(--orange);
  background:rgba(255,107,26,.08);
}
.page-about .about-net li:nth-child(3n+2):hover{
  border-color:var(--mint);
  color:var(--mint);
  background:rgba(37,240,178,.08);
}
.page-about .about-net li:nth-child(3n):hover{
  border-color:var(--gold);
  color:var(--gold);
  background:rgba(242,193,92,.08);
}

/* ---------- 三级体系 ---------- */
.page-about .about-levels{
  display:grid;
  gap:.6rem;
  margin:1.25rem 0 0;
  padding:0;
  list-style:none;
}
.page-about .about-level{
  display:grid;
  grid-template-columns:auto minmax(0,1fr);
  gap:.85rem;
  align-items:start;
  padding:1rem 1.1rem;
  border:1px solid var(--line);
  border-left:3px solid var(--orange);
  border-radius:var(--r-md);
  background:var(--surface);
}
.page-about .about-level:nth-child(2){border-left-color:var(--mint);}
.page-about .about-level:nth-child(3){border-left-color:var(--gold);}
.page-about .about-level-num{
  font-family:var(--font-display);
  font-weight:800;
  font-size:1.45rem;
  line-height:1;
  color:var(--mist);
}
.page-about .about-level h3{
  margin:0 0 .3rem;
  font-family:var(--font-heading);
  font-size:1rem;
  font-weight:600;
  color:var(--mist);
}
.page-about .about-level p{
  margin:0;
  max-width:none;
  font-size:.92rem;
  line-height:1.72;
  color:rgba(234,242,247,.74);
}

/* ---------- 档案区 ---------- */
.page-about .about-archive{
  margin-top:1.25rem;
  padding:var(--about-pad);
  border:1px solid rgba(234,242,247,.16);
  border-radius:var(--r-md);
}
.page-about .about-archive-grid{
  display:grid;
  gap:.9rem;
}
.page-about .about-archive-card{
  padding:1rem 1.1rem;
  border:1px solid rgba(234,242,247,.12);
  border-radius:var(--r-sm);
  background:rgba(6,24,38,.4);
}
.page-about .about-archive-card h3{
  margin:.65rem 0 .4rem;
  font-family:var(--font-heading);
  font-size:1rem;
  font-weight:600;
  color:var(--mist);
}
.page-about .about-archive-card p{
  margin:0;
  max-width:none;
  font-size:.92rem;
  line-height:1.75;
  color:rgba(234,242,247,.76);
}
.page-about .about-archive-note{
  margin:1rem 0 0;
  max-width:none;
  font-size:.88rem;
  line-height:1.75;
  color:var(--slate);
}
.page-about .about-archive-note a{
  color:var(--mint);
  text-decoration:none;
  border-bottom:1px solid rgba(37,240,178,.35);
}
.page-about .about-archive-note a:hover,
.page-about .about-archive-note a:focus-visible{
  color:var(--mist);
  border-bottom-color:var(--mist);
}

/* ---------- 下一阶段 ---------- */
.page-about .about-next-list{
  display:grid;
  gap:.7rem;
  margin:1.25rem 0 0;
  padding:0;
  list-style:none;
}
.page-about .about-next-item{
  display:grid;
  grid-template-columns:auto minmax(0,1fr);
  gap:.85rem;
  align-items:start;
  padding:.9rem 1rem;
  border:1px solid var(--line-soft);
  border-radius:var(--r-sm);
  background:var(--surface);
}
.page-about .about-next-mark{
  width:.55rem;
  height:.55rem;
  margin-top:.45rem;
  background:var(--orange);
  transform:skewX(var(--skew));
  flex:0 0 auto;
}
.page-about .about-next-item h3{
  margin:0 0 .3rem;
  font-family:var(--font-heading);
  font-size:.98rem;
  font-weight:600;
  color:var(--mist);
}
.page-about .about-next-item p{
  margin:0;
  max-width:none;
  font-size:.92rem;
  line-height:1.72;
  color:rgba(234,242,247,.74);
}

.page-about .about-cta{
  margin-top:1.5rem;
  padding:var(--about-pad);
  border:1px solid var(--line);
  border-radius:var(--r-md);
  background:linear-gradient(120deg, rgba(255,107,26,.12), rgba(37,240,178,.06) 80%);
}
.page-about .about-cta p{
  margin:0 0 1rem;
  max-width:52ch;
  color:rgba(234,242,247,.86);
}
.page-about .about-cta-actions{
  display:flex;
  flex-wrap:wrap;
  gap:.7rem;
}

/* ---------- 响应式 ---------- */
@media (min-width:700px){
  .page-about .about-archive-grid{
    grid-template-columns:repeat(2,minmax(0,1fr));
  }
  .page-about .about-level:nth-child(2){margin-left:1.25rem;}
  .page-about .about-level:nth-child(3){margin-left:2.5rem;}
}

@media (min-width:860px){
  .page-about .about-hero-grid{
    grid-template-columns:minmax(0,1.34fr) minmax(0,.66fr);
    align-items:end;
  }
  .page-about .about-versions{
    grid-template-columns:minmax(0,.82fr) minmax(0,1.18fr);
    align-items:start;
  }
  .page-about .about-version-list{
    position:relative;
    padding-left:1rem;
  }
  .page-about .about-version-list::before{
    content:"";
    position:absolute;
    left:.3rem;
    top:.5rem;
    bottom:.5rem;
    width:1px;
    background:linear-gradient(180deg,var(--slate),var(--gold),var(--mist),var(--orange));
    opacity:.45;
  }
}

@media (min-width:1000px){
  .page-about .about-body{
    grid-template-columns:var(--about-index-w) minmax(0,1fr);
    align-items:start;
  }
  .page-about .about-index{
    position:sticky;
    top:clamp(5.5rem,11vh,7rem);
    overflow:visible;
  }
  .page-about .about-index-list{
    flex-direction:column;
    gap:.1rem;
  }
  .page-about .about-flow{
    min-width:0;
  }
}
<<<END>>>