.page-about{
  --era-cat: var(--cat-clean);
  --stat-c: var(--cat-clean);
  --partner-c: var(--cat-clean);
  position: relative;
  background:
    radial-gradient(120% 55% at 85% 0%, rgba(30,127,184,.12), transparent 62%),
    linear-gradient(180deg, var(--paper-cold) 0%, #e9f1f7 42%, var(--paper-cold) 100%);
  color: var(--ink);
  font-family: var(--font-sans);
  padding-bottom: clamp(36px, 6vw, 72px);
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */
.page-about .story-lead{
  padding: clamp(16px, 3vw, 30px) 0 0;
}

.page-about .crumbs{
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--mist);
  margin: 0 0 clamp(18px, 3.4vw, 34px);
}
.page-about .crumbs a{
  color: var(--ink-soft);
  text-decoration: none;
  border-bottom: 1px solid var(--line);
  padding-bottom: 1px;
  transition: color .18s ease, border-color .18s ease;
}
.page-about .crumbs a:hover,
.page-about .crumbs a:focus-visible{
  color: var(--cat-clean);
  border-color: var(--cat-clean);
}

.page-about .story-lead__grid{
  display: grid;
  gap: clamp(22px, 4vw, 40px);
}

.page-about .story-lead h1{
  margin: 0 0 clamp(14px, 2.2vw, 22px);
  font-size: clamp(30px, 6.6vw, 60px);
  font-weight: 900;
  line-height: 1.07;
  letter-spacing: -.02em;
  color: var(--ink);
}
.page-about .story-lead h1::after{
  content: "";
  display: block;
  width: 72px;
  height: 6px;
  margin-top: clamp(14px, 2vw, 22px);
  background: linear-gradient(90deg,
    var(--cat-clean) 0 25%,
    var(--cat-pipe) 25% 50%,
    var(--cat-repair) 50% 75%,
    var(--cat-house) 75% 100%);
}

.page-about .story-lead__text{
  margin: 0;
  max-width: 62ch;
  font-size: clamp(16px, 1.6vw, 17.5px);
  line-height: 1.85;
  color: var(--ink-soft);
}

.page-about .story-file{
  position: relative;
  padding: clamp(20px, 3vw, 28px);
  background: var(--ink);
  color: var(--paper-cold);
  border-radius: 2px;
  box-shadow: var(--shadow-float);
  overflow: hidden;
}
.page-about .story-file::after{
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 4px;
  background: linear-gradient(90deg,
    var(--cat-clean) 0 25%,
    var(--cat-pipe) 25% 50%,
    var(--cat-repair) 50% 75%,
    var(--cat-house) 75% 100%);
}
.page-about .story-file__label{
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .24em;
  color: var(--mist);
}
.page-about .story-file dl{
  margin: 0;
  display: grid;
  gap: 11px;
}
.page-about .story-file dl > div{
  display: grid;
  grid-template-columns: 54px minmax(0, 1fr);
  gap: 10px;
  align-items: baseline;
  padding-bottom: 10px;
  border-bottom: 1px dashed rgba(220, 233, 242, .22);
}
.page-about .story-file dl > div:last-child{
  padding-bottom: 0;
  border-bottom: 0;
}
.page-about .story-file dt{
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--mist);
}
.page-about .story-file dd{
  margin: 0;
  font-size: 15px;
  line-height: 1.6;
  color: var(--paper-cold);
}

.page-about .story-stats{
  list-style: none;
  margin: clamp(26px, 4vw, 42px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.page-about .story-stats li{
  position: relative;
  padding: clamp(14px, 2vw, 20px) clamp(12px, 1.8vw, 18px);
  background: rgba(250, 246, 239, .78);
}
.page-about .story-stats li::before{
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: var(--stat-c);
}
.page-about .story-stats li:nth-child(1){ --stat-c: var(--cat-clean); }
.page-about .story-stats li:nth-child(2){ --stat-c: var(--cat-pipe); }
.page-about .story-stats li:nth-child(3){ --stat-c: var(--cat-repair); }
.page-about .story-stats li:nth-child(4){ --stat-c: var(--cat-house); }

.page-about .stat__num{
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(24px, 3.2vw, 34px);
  font-weight: 600;
  line-height: 1.05;
  letter-spacing: -.01em;
  color: var(--stat-c);
}
.page-about .stat__label{
  display: block;
  margin-top: 8px;
  font-size: 13px;
  line-height: 1.55;
  color: var(--mist);
}

/* ---------- 两栏骨架 ---------- */
.page-about .story-body{
  display: grid;
  gap: clamp(26px, 4vw, 48px);
  padding-top: clamp(30px, 5vw, 66px);
}

.page-about .story-index{
  display: none;
}
.page-about .story-index__cap{
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .24em;
  color: var(--mist);
}
.page-about .story-index ol{
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
}
.page-about .story-index a{
  display: grid;
  grid-template-columns: 26px minmax(0, 1fr);
  gap: 8px;
  align-items: baseline;
  padding: 9px 8px;
  font-size: 13.5px;
  line-height: 1.5;
  color: var(--ink-soft);
  text-decoration: none;
  border-left: 2px solid transparent;
  transition: background-color .2s ease, color .2s ease, border-color .2s ease;
}
.page-about .story-index a:hover,
.page-about .story-index a:focus-visible{
  background: rgba(250, 246, 239, .9);
  color: var(--ink);
  border-left-color: var(--cat-clean);
}
.page-about .story-index .mono{
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--mist);
}

/* ---------- 时间轴 ---------- */
.page-about .story-flow{
  display: grid;
  gap: clamp(26px, 4vw, 44px);
}

.page-about .era{
  position: relative;
  padding-left: 34px;
}
.page-about .era::before{
  content: "";
  position: absolute;
  left: 7px;
  top: 26px;
  bottom: calc(clamp(26px, 4vw, 44px) * -1);
  width: 1px;
  background: linear-gradient(180deg, var(--line-strong), var(--line));
}
.page-about .era:last-of-type::before{
  display: none;
}
.page-about .era__dot{
  position: absolute;
  left: 0;
  top: 8px;
  width: 15px;
  height: 15px;
  border-radius: 50%;
  border: 2px solid var(--era-cat);
  background: var(--paper-warm);
  box-shadow: 0 0 0 4px rgba(220, 233, 242, .9);
}
.page-about .era__gauge{
  margin: 0 0 10px;
}
.page-about .era__when{
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: .08em;
  color: var(--era-cat);
}

.page-about .era--clean{ --era-cat: var(--cat-clean); }
.page-about .era--pipe{ --era-cat: var(--cat-pipe); }
.page-about .era--repair{ --era-cat: var(--cat-repair); }
.page-about .era--house{ --era-cat: var(--cat-house); }
.page-about .era--now{ --era-cat: var(--mist); }

.page-about .era__panel{
  position: relative;
  padding: clamp(18px, 2.8vw, 30px);
  background: var(--paper-warm);
  border: 1px solid var(--line-paper);
  border-left: 3px solid var(--era-cat);
  border-radius: 2px;
  box-shadow: var(--shadow-panel);
}
.page-about .era__panel h3{
  margin: 12px 0 12px;
  font-size: clamp(20px, 2.4vw, 27px);
  font-weight: 900;
  line-height: 1.28;
  letter-spacing: -.01em;
  color: var(--ink);
}
.page-about .era__panel p{
  margin: 0 0 12px;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink-soft);
}
.page-about .era__panel p:last-of-type{
  margin-bottom: 0;
}

.page-about .tag{
  display: inline-block;
  padding: 4px 10px;
  border: 1px solid currentColor;
  border-radius: 2px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .14em;
  color: var(--ink-soft);
  background: rgba(22, 34, 46, .04);
}
.page-about .tag--clean{
  color: var(--cat-clean);
  background: rgba(30, 127, 184, .09);
}
.page-about .tag--pipe{
  color: var(--cat-pipe);
  background: rgba(222, 138, 22, .1);
}
.page-about .tag--repair{
  color: var(--cat-repair);
  background: rgba(53, 111, 128, .1);
}
.page-about .tag--house{
  color: var(--cat-house);
  background: rgba(90, 122, 68, .1);
}

.page-about .era__figure{
  margin: clamp(16px, 2.4vw, 22px) 0 0;
}
.page-about .era__figure img{
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  border: 1px solid var(--line-paper);
  border-radius: 2px;
}
.page-about .media__cap{
  margin-top: 8px;
  font-size: 12.5px;
  line-height: 1.65;
  color: var(--mist);
}

.page-about .era__next{
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 14px;
  padding-bottom: 3px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: .06em;
  color: var(--ink-soft);
  text-decoration: none;
  border-bottom: 1px dashed var(--line-strong);
  transition: color .2s ease, border-color .2s ease;
}
.page-about .era__next::after{
  content: "↓";
}
.page-about .era__next:hover,
.page-about .era__next:focus-visible{
  color: var(--era-cat);
  border-color: var(--era-cat);
}

/* ---------- 章节 ---------- */
.page-about .chapter{
  margin-top: clamp(46px, 6vw, 78px);
}
.page-about .chapter__head{
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: clamp(14px, 2vw, 20px);
  padding-bottom: 12px;
  border-bottom: 1px solid var(--line-strong);
}
.page-about .chapter__no{
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--mist);
}
.page-about .chapter h2{
  margin: 0;
  font-size: clamp(22px, 3.2vw, 34px);
  font-weight: 900;
  line-height: 1.22;
  letter-spacing: -.01em;
  color: var(--ink);
}
.page-about .chapter__lead{
  margin: 0 0 clamp(14px, 2vw, 20px);
  max-width: 64ch;
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink-soft);
}
.page-about .chapter__grid{
  display: grid;
  gap: clamp(18px, 3vw, 32px);
  align-items: start;
}
.page-about .chapter__body p{
  margin: 0 0 14px;
  max-width: 66ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink-soft);
}
.page-about .chapter__body p:last-child{
  margin-bottom: 0;
}
.page-about .chapter__figure{
  margin: 0;
}
.page-about .chapter__figure img{
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border: 1px solid var(--line-paper);
  border-radius: 2px;
}
.page-about .chapter__figure--square img{
  aspect-ratio: 1 / 1;
}

.page-about .crew-figures{
  list-style: none;
  margin: clamp(18px, 2.6vw, 26px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}
.page-about .crew-figures li{
  padding: 14px;
  background: rgba(250, 246, 239, .68);
  border: 1px dashed var(--line-strong);
  border-radius: 2px;
}
.page-about .crew-figures__num{
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(24px, 3vw, 32px);
  font-weight: 600;
  line-height: 1;
  color: var(--ink);
}
.page-about .crew-figures__label{
  display: block;
  margin-top: 8px;
  font-size: 13px;
  line-height: 1.55;
  color: var(--mist);
}

.page-about .hand-note{
  margin: clamp(16px, 2.4vw, 24px) 0 0;
  padding-left: 14px;
  border-left: 3px solid var(--cat-repair);
  font-family: var(--font-hand);
  font-size: clamp(17px, 2vw, 21px);
  line-height: 1.6;
  color: var(--cat-repair);
}

/* ---------- 协作伙伴折叠组 ---------- */
.page-about .partners{
  display: grid;
  gap: 10px;
}
.page-about .partner{
  background: var(--paper-warm);
  border: 1px solid var(--line-paper);
  border-left: 3px solid var(--partner-c);
  border-radius: 2px;
  box-shadow: var(--shadow-panel);
}
.page-about .partner[open]{
  box-shadow: var(--shadow-float);
}
.page-about .partner--estate{ --partner-c: var(--cat-house); }
.page-about .partner--brand{ --partner-c: var(--cat-clean); }
.page-about .partner--street{ --partner-c: var(--cat-pipe); }
.page-about .partner--store{ --partner-c: var(--cat-repair); }

.page-about .partner summary{
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 15px clamp(14px, 2vw, 20px);
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
  cursor: pointer;
  list-style: none;
}
.page-about .partner summary::-webkit-details-marker{
  display: none;
}
.page-about .partner summary::after{
  content: "+";
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 20px;
  line-height: 1;
  color: var(--partner-c);
}
.page-about .partner[open] summary::after{
  content: "–";
}
.page-about .partner summary:focus-visible{
  outline: 2px solid var(--cat-clean);
  outline-offset: -2px;
}
.page-about .partner__body{
  padding: 0 clamp(14px, 2vw, 20px) clamp(16px, 2.4vw, 22px);
}
.page-about .partner__body p{
  margin: 0 0 10px;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--ink-soft);
}
.page-about .partner__list{
  margin: 0;
  padding-left: 18px;
  display: grid;
  gap: 6px;
}
.page-about .partner__list li{
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--ink-soft);
}

/* ---------- 上门规矩 ---------- */
.page-about .rules{
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.page-about .rules li{
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: 12px;
  align-items: start;
  padding: clamp(14px, 2vw, 18px) clamp(12px, 2vw, 18px);
  background: rgba(250, 246, 239, .8);
}
.page-about .rules__no{
  font-family: var(--font-mono);
  font-size: 18px;
  line-height: 1.35;
  color: var(--mist);
}
.page-about .rules p{
  margin: 0;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--ink-soft);
}
.page-about .rules li:nth-child(1) .rules__no{ color: var(--cat-clean); }
.page-about .rules li:nth-child(2) .rules__no{ color: var(--cat-pipe); }
.page-about .rules li:nth-child(3) .rules__no{ color: var(--cat-repair); }
.page-about .rules li:nth-child(4) .rules__no{ color: var(--cat-house); }
.page-about .rules li:nth-child(5) .rules__no{ color: var(--warn-3); }

/* ---------- 结尾 ---------- */
.page-about .story-cta{
  position: relative;
  margin-top: clamp(50px, 7vw, 92px);
  padding: clamp(38px, 6vw, 68px) 0;
  background: var(--ink);
  color: var(--paper-cold);
}
.page-about .story-cta::before{
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 5px;
  background: linear-gradient(90deg,
    var(--cat-clean) 0 25%,
    var(--cat-pipe) 25% 50%,
    var(--cat-repair) 50% 75%,
    var(--cat-house) 75% 100%);
}
.page-about .story-cta__inner{
  display: grid;
  gap: clamp(22px, 3.5vw, 40px);
}
.page-about .story-cta h2{
  margin: 0 0 12px;
  font-size: clamp(22px, 3vw, 32px);
  font-weight: 900;
  line-height: 1.25;
  letter-spacing: -.01em;
  color: var(--paper-cold);
}
.page-about .story-cta p{
  margin: 0;
  max-width: 52ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: rgba(220, 233, 242, .84);
}
.page-about .story-cta__links{
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .btn{
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 11px 20px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  transition: transform .18s ease, background-color .18s ease, border-color .18s ease, color .18s ease;
}
.page-about .btn:hover{
  transform: translateY(-1px);
}
.page-about .btn--primary{
  background: var(--cat-clean);
  color: #fff;
}
.page-about .btn--primary:hover{
  background: #1a6d9e;
}
.page-about .btn--ghost{
  border-color: rgba(220, 233, 242, .42);
  color: var(--paper-cold);
}
.page-about .btn--ghost:hover{
  border-color: var(--paper-cold);
  background: rgba(220, 233, 242, .1);
}
.page-about .btn:focus-visible{
  outline: 2px solid var(--warn-1);
  outline-offset: 2px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 760px){
  .page-about .story-stats{
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .crew-figures{
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 900px){
  .page-about .story-lead__grid{
    grid-template-columns: minmax(0, 1.55fr) minmax(280px, .85fr);
    align-items: start;
    gap: clamp(28px, 4vw, 60px);
  }
  .page-about .chapter__grid{
    grid-template-columns: minmax(0, 1.12fr) minmax(0, .88fr);
  }
  .page-about .chapter__grid--flip{
    grid-template-columns: minmax(0, .88fr) minmax(0, 1.12fr);
  }
  .page-about .story-cta__inner{
    grid-template-columns: minmax(0, 1.1fr) minmax(0, .9fr);
    align-items: center;
  }
}

@media (min-width: 1000px){
  .page-about .era{
    padding-left: 156px;
  }
  .page-about .era::before{
    left: 129px;
    top: 32px;
  }
  .page-about .era__dot{
    left: 122px;
    top: 9px;
  }
  .page-about .era__gauge{
    position: absolute;
    left: 0;
    top: 2px;
    width: 118px;
    margin: 0;
    text-align: right;
  }
  .page-about .era__when{
    display: block;
    font-size: 19px;
    letter-spacing: .02em;
  }
}

@media (min-width: 1080px){
  .page-about .story-body{
    grid-template-columns: 178px minmax(0, 1fr);
    column-gap: clamp(32px, 4vw, 62px);
  }
  .page-about .story-index{
    display: block;
    position: sticky;
    top: 112px;
    align-self: start;
  }
}

@media (prefers-reduced-motion: reduce){
  .page-about .btn,
  .page-about .era__next,
  .page-about .story-index a,
  .page-about .crumbs a{
    transition: none;
  }
  .page-about .btn:hover{
    transform: none;
  }
}