.page-about{
  --about-hero-media-w: min(100%, 32rem);
  --tl-year-col: 4.2rem;
  --tl-mark-col: 1.5rem;
  --tl-card-gap: .9rem;
  --tl-line-offset: 4.95rem;
  --tl-year-size: clamp(2.4rem, 9vw, 5.5rem);
  --now-card-min-h: 15.5rem;
  color: var(--text-main);
  background: var(--light);
}

/* ============ Hero ============ */
.page-about .about-hero{
  position: relative;
  background:
    radial-gradient(circle at 82% 12%, rgba(0,255,179,.14), transparent 34%),
    linear-gradient(135deg, var(--deep) 0%, var(--primary) 55%, var(--secondary) 100%);
  color: var(--text-on-dark);
  overflow: hidden;
}
.page-about .about-hero::after{
  content:"";
  position:absolute;
  right:-6rem;
  bottom:-6rem;
  width:20rem;
  height:20rem;
  border:2.4rem solid var(--accent);
  border-radius:50%;
  opacity:.1;
  pointer-events:none;
}
.page-about .about-hero__inner{
  display:grid;
  gap:2.5rem;
  align-items:center;
  position:relative;
  z-index:1;
}
.page-about .about-hero__copy{
  max-width:48rem;
}
.page-about .about-hero__copy .breadcrumbs{
  margin-bottom:1.25rem;
}
.page-about .about-hero__kicker{
  display:inline-block;
  color:var(--accent);
  font-family:var(--font-head);
  font-size:.75rem;
  letter-spacing:.14em;
  text-transform:uppercase;
  border:1px solid rgba(0,255,179,.5);
  padding:.35rem .75rem;
  margin-bottom:1.1rem;
}
.page-about .about-hero h1{
  font-family:var(--font-head);
  font-size:clamp(2.1rem,4.6vw,4rem);
  line-height:1.08;
  margin:.35em 0 .5em;
  max-width:20em;
  letter-spacing:-.02em;
}
.page-about .about-hero .lead{
  font-size:1.125rem;
  line-height:1.75;
  max-width:37em;
  color:rgba(255,255,255,.86);
  margin-bottom:1rem;
}
.page-about .about-hero__desc{
  max-width:42em;
  color:rgba(255,255,255,.72);
  line-height:1.75;
}
.page-about .about-hero__actions{
  display:flex;
  flex-wrap:wrap;
  gap:.85rem;
  margin-top:1.5rem;
}
.page-about .about-hero__quote{
  margin:1.65rem 0 0;
  padding:.9rem 1.1rem;
  border-left:0;
  border-top:3px solid var(--gold);
  background:rgba(255,209,102,.08);
  font-size:1.05rem;
  font-weight:700;
  max-width:32rem;
}
.page-about .about-hero__quote p{
  margin:0;
  color:var(--gold);
  line-height:1.6;
}
.page-about .about-hero__media{
  position:relative;
  width:var(--about-hero-media-w);
  justify-self:center;
}
.page-about .about-hero__media-frame{
  border:3px solid var(--accent);
  box-shadow:var(--shadow-accent);
  transform:rotate(1.2deg);
  background:var(--secondary);
}
.page-about .about-hero__media-frame img{
  display:block;
  width:100%;
  height:auto;
  object-fit:cover;
}
.page-about .about-hero__stamp{
  position:absolute;
  right:-.5rem;
  bottom:-1rem;
  background:var(--gold);
  color:var(--primary);
  font-family:var(--font-head);
  font-size:.72rem;
  line-height:1.3;
  padding:.55rem .95rem;
  letter-spacing:.04em;
  transform:rotate(-4deg);
  border:2px solid var(--primary);
  box-shadow:4px 4px 0 rgba(255,255,255,.18);
  max-width:11rem;
}

/* ============ 斜向分隔 ============ */
.page-about .divider-slash{
  height:1.6rem;
  background:repeating-linear-gradient(115deg, var(--accent) 0 1.4rem, var(--primary) 1.4rem 2.8rem);
  border-top:2px solid var(--primary);
  border-bottom:2px solid var(--primary);
}
.page-about .divider-slash--reverse{
  background:repeating-linear-gradient(65deg, var(--gold) 0 1.4rem, var(--deep) 1.4rem 2.8rem);
}

/* ============ 时间线 ============ */
.page-about .about-rail{
  position:relative;
}
.page-about .about-rail__head{
  max-width:44rem;
  margin-bottom:3rem;
}
.page-about .about-rail__eyebrow{
  color:var(--accent-deep);
  font-family:var(--font-head);
  font-size:.85rem;
  letter-spacing:.1em;
  margin-bottom:.4rem;
}
.page-about .about-rail__sub-lead{
  margin-top:.85rem;
  color:var(--text-sub);
  max-width:36rem;
}
.page-about .about-rail__line{
  list-style:none;
  margin:0;
  padding:0;
  display:grid;
  gap:2.6rem;
}
.page-about .about-rail__item{
  display:grid;
  grid-template-columns: var(--tl-year-col) var(--tl-mark-col) 1fr;
  grid-template-rows:auto 1fr;
  column-gap:var(--tl-card-gap);
  align-items:start;
}
.page-about .about-rail__year{
  grid-column:1;
  grid-row:1;
  justify-self:start;
  display:inline-block;
  background:var(--primary);
  color:var(--accent);
  font-family:var(--font-head);
  font-weight:900;
  font-size:var(--tl-year-size);
  line-height:1;
  padding:.16em .5em .16em .3em;
  clip-path:polygon(0 0, 100% 0, calc(100% - .55rem) 100%, 0 100%);
  -webkit-clip-path:polygon(0 0, 100% 0, calc(100% - .55rem) 100%, 0 100%);
}
.page-about .about-rail__mark{
  grid-column:2;
  grid-row:1 / span 2;
  position:relative;
}
.page-about .about-rail__mark::before{
  content:"";
  position:absolute;
  left:50%;
  top:0;
  bottom:0;
  width:3px;
  transform:translateX(-50%);
  background:linear-gradient(var(--accent-deep), var(--secondary));
}
.page-about .about-rail__dot{
  position:sticky;
  top:calc(var(--header-h) + 1rem);
  left:50%;
  transform:translateX(-50%);
  display:block;
  width:16px;
  height:16px;
  border-radius:50%;
  background:var(--accent);
  border:3px solid var(--primary);
  box-shadow:0 0 0 6px rgba(0,255,179,.18);
}
.page-about .about-rail__card{
  grid-column:3;
  grid-row:2;
  background:#ffffff;
  border:3px solid var(--primary);
  box-shadow:var(--shadow-hard);
  padding:1.25rem 1.35rem;
  transition:transform .25s ease, box-shadow .25s ease, border-color .25s ease;
}
.page-about .about-rail__item:hover .about-rail__card{
  transform:translate(4px, -4px);
  box-shadow:12px 12px 0 rgba(0,255,179,.28);
  border-color:var(--accent-deep);
}
.page-about .about-rail__card h3{
  font-family:var(--font-head);
  font-size:1.25rem;
  line-height:1.4;
  margin:0 0 .45rem;
}
.page-about .about-rail__card p{
  font-size:.95rem;
  line-height:1.75;
  color:var(--text-main);
  margin:0 0 .7rem;
}
.page-about .about-rail__note{
  border-top:2px dashed var(--secondary);
  padding-top:.7rem;
  font-size:.84rem;
  color:var(--text-sub);
  display:flex;
  gap:.4rem;
  align-items:baseline;
}
.page-about .about-rail__note::before{
  content:"//";
  color:var(--accent-deep);
  font-weight:900;
}
.page-about .about-rail__media{
  border:2px solid var(--secondary);
  background:var(--secondary);
  margin-bottom:.85rem;
}
.page-about .about-rail__media img{
  display:block;
  width:100%;
  height:auto;
  object-fit:cover;
}

/* ============ 本地基因 ============ */
.page-about .about-local{
  color:var(--text-on-dark);
}
.page-about .about-local__grid{
  display:grid;
  gap:2.5rem;
  align-items:center;
}
.page-about .about-local__copy{
  order:1;
}
.page-about .about-local__media{
  order:2;
}
.page-about .about-local__eyebrow{
  color:var(--accent);
  font-family:var(--font-head);
  font-size:.85rem;
  letter-spacing:.1em;
  margin-bottom:.4rem;
}
.page-about .about-local__copy h2{
  font-family:var(--font-head);
  font-size:clamp(1.75rem,3.4vw,3rem);
  line-height:1.12;
  margin:.3em 0 .55em;
  max-width:15em;
}
.page-about .about-local__lead{
  color:rgba(255,255,255,.8);
  max-width:38rem;
  line-height:1.75;
}
.page-about .about-local__list{
  list-style:none;
  padding:0;
  margin:1.3rem 0;
  display:grid;
  gap:.9rem;
}
.page-about .about-local__list li{
  color:rgba(255,255,255,.82);
  padding-left:1.5rem;
  position:relative;
  line-height:1.7;
  font-size:.95rem;
}
.page-about .about-local__list li::before{
  content:"";
  position:absolute;
  left:0;
  top:.6em;
  width:.55em;
  height:.55em;
  background:var(--accent);
  transform:skewX(-20deg);
}
.page-about .about-local__mark{
  display:flex;
  flex-wrap:wrap;
  gap:.65rem;
}
.page-about .about-local__frame{
  border:3px solid var(--accent);
  box-shadow:var(--shadow-accent);
  background:var(--secondary);
}
.page-about .about-local__frame img{
  display:block;
  width:100%;
  height:auto;
  object-fit:cover;
}

/* ============ 今天与明天 ============ */
.page-about .about-now__head{
  max-width:46rem;
}
.page-about .about-now__eyebrow{
  color:var(--accent-deep);
  font-family:var(--font-head);
  font-size:.85rem;
  letter-spacing:.1em;
  margin-bottom:.4rem;
}
.page-about .about-now__head .lead{
  margin-top:.9rem;
  color:var(--text-sub);
  max-width:40rem;
}
.page-about .about-now__cards{
  display:grid;
  gap:1.5rem;
  margin:3rem 0 2.5rem;
}
.page-about .about-now__card{
  perspective:1400px;
}
.page-about .about-now__card-inner{
  position:relative;
  min-height:var(--now-card-min-h);
  transform-style:preserve-3d;
  transition:transform .5s ease;
}
.page-about .about-now__card:hover .about-now__card-inner,
.page-about .about-now__card:focus-within .about-now__card-inner{
  transform:rotateY(180deg);
}
.page-about .about-now__card-front,
.page-about .about-now__card-back{
  position:absolute;
  inset:0;
  backface-visibility:hidden;
  -webkit-backface-visibility:hidden;
}
.page-about .about-now__card-front{
  background:#ffffff;
  border:3px solid var(--primary);
  box-shadow:var(--shadow-hard);
  padding:1.4rem 1.35rem;
  display:flex;
  flex-direction:column;
}
.page-about .about-now__card-back{
  transform:rotateY(180deg);
  background:var(--primary);
  border:3px solid var(--accent);
  box-shadow:var(--shadow-hard);
  color:var(--text-on-dark);
  padding:1.4rem;
  display:flex;
  flex-direction:column;
  justify-content:space-between;
  gap:1rem;
}
.page-about .about-now__index{
  font-family:var(--font-head);
  font-size:3rem;
  line-height:1;
  font-weight:900;
  color:var(--accent-deep);
  opacity:.35;
}
.page-about .about-now__card-front h3{
  font-family:var(--font-head);
  font-size:1.3rem;
  margin:.8rem 0 .4rem;
}
.page-about .about-now__card-front p{
  font-size:.92rem;
  line-height:1.7;
  color:var(--text-main);
  margin:0 0 .8rem;
}
.page-about .about-now__card-front .about-now__stat{
  margin-top:auto;
  border-top:2px solid var(--accent);
  padding-top:.65rem;
  font-size:.8rem;
  font-weight:700;
  color:var(--text-sub);
}
.page-about .about-now__card-back p{
  font-size:.92rem;
  line-height:1.7;
  color:rgba(255,255,255,.85);
  margin:0;
}
.page-about .about-now__cta{
  display:flex;
  flex-wrap:wrap;
  gap:1rem;
}

/* ============ 桌面增强 ============ */
@media (min-width: 760px) {
  .page-about{
    --tl-year-col:minmax(6rem, 10rem);
    --tl-mark-col:2.5rem;
    --tl-card-gap:2rem;
    --tl-year-size:clamp(3.5rem, 8vw, 7rem);
    --now-card-min-h:17rem;
  }
  .page-about .about-hero__inner{
    grid-template-columns:1.1fr .8fr;
    gap:4rem;
    align-items:center;
  }
  .page-about .about-hero__media{
    justify-self:end;
  }
  .page-about .about-rail__item{
    column-gap:var(--tl-card-gap);
  }
  .page-about .about-rail__year{
    justify-self:end;
    text-align:right;
  }
  .page-about .about-rail__dot{
    transform:translateX(-50%);
  }
  .page-about .about-local__grid{
    grid-template-columns:1fr 1fr;
    gap:4rem;
  }
  .page-about .about-local__copy{
    order:1;
  }
  .page-about .about-local__media{
    order:2;
  }
  .page-about .about-now__cards{
    grid-template-columns:repeat(3, 1fr);
    align-items:stretch;
  }
}

/* ============ 窄屏无 hover：卡片静态展示 ============ */
@media (hover: none) and (max-width: 759px){
  .page-about .about-now__card-inner{
    min-height:auto;
  }
  .page-about .about-now__card-front,
  .page-about .about-now__card-back{
    position:static;
    transform:none;
  }
  .page-about .about-now__card-back{
    margin-top:1rem;
    background:var(--primary);
    color:var(--text-on-dark);
  }
}