.page-about{
  --ab-rail: 168px;
  --ab-gap: clamp(20px, 3.4vw, 44px);
  --ab-sec-pad: clamp(38px, 5.6vw, 76px);
}

.page-about .breadcrumb{
  margin-block: 0 clamp(14px, 2vw, 26px);
}

/* 首屏 */
.page-about .ab-hero{
  position: relative;
  padding-block: clamp(10px, 2vw, 22px) clamp(40px, 6vw, 84px);
  overflow: clip;
}

.page-about .ab-hero-inner{
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--ab-gap);
  align-items: center;
}

.page-about .ab-hero h1{
  margin: 0 0 clamp(16px, 2.4vw, 24px);
  font-size: clamp(2.1rem, 6.6vw, 4.4rem);
  line-height: 1.08;
  letter-spacing: 0.04em;
  color: var(--paper);
  max-width: 18ch;
  text-wrap: balance;
}

.page-about .ab-lede{
  margin: 0 0 clamp(24px, 3.4vw, 36px);
  max-width: 58ch;
  color: var(--stargray);
}

.page-about .ab-hero-figures{
  display: flex;
  flex-wrap: wrap;
  gap: clamp(18px, 3.2vw, 44px);
  padding-top: clamp(14px, 2vw, 20px);
  border-top: 1px solid var(--hair);
}

.page-about .ab-figure{
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-width: 96px;
}

.page-about .ab-figure-n{
  font-size: clamp(1.55rem, 3.4vw, 2.35rem);
  font-weight: 600;
  line-height: 1;
}

.page-about .ab-figure-t{
  font-size: var(--fs-12);
  letter-spacing: 0.08em;
  color: var(--stargray);
}

.page-about .ab-hero-figure{
  margin: 0;
}

.page-about .ab-frame{
  position: relative;
  background: linear-gradient(155deg, var(--night), var(--void));
  border: 1px solid var(--hair-strong);
  padding: 10px;
}

.page-about .ab-frame::before,
.page-about .ab-frame::after{
  content: "";
  position: absolute;
  width: 28px;
  height: 28px;
  pointer-events: none;
}

.page-about .ab-frame::before{
  top: -1px;
  left: -1px;
  border-top: 1px solid var(--electric);
  border-left: 1px solid var(--electric);
}

.page-about .ab-frame::after{
  right: -1px;
  bottom: -1px;
  border-right: 1px solid var(--electric);
  border-bottom: 1px solid var(--electric);
}

.page-about .ab-frame img{
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.92);
}

.page-about .ab-hero-figure figcaption{
  margin-top: 12px;
}

/* 章节轨道骨架 */
.page-about .ab-sec{
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(16px, 2.6vw, 30px);
  border-top: 1px solid var(--hair);
  padding-block: var(--ab-sec-pad);
}

.page-about .ab-sec--last{
  border-bottom: 1px solid var(--hair);
}

.page-about .ab-rail{
  display: flex;
  align-items: baseline;
  gap: 12px;
}

.page-about .ab-rail-num{
  font-size: clamp(1.3rem, 2.6vw, 1.9rem);
  font-weight: 600;
  line-height: 1;
  color: var(--nebula);
}

.page-about .ab-rail-label{
  font-size: var(--fs-12);
  letter-spacing: 0.14em;
  color: var(--stargray);
}

.page-about .ab-body h2{
  margin: 0 0 clamp(14px, 2vw, 20px);
  font-size: clamp(1.5rem, 3.1vw, 2.5rem);
  line-height: 1.22;
  letter-spacing: 0.04em;
  color: var(--paper);
  max-width: 22ch;
}

.page-about .ab-body p{
  margin: 0 0 16px;
  max-width: 68ch;
  color: var(--stargray);
  line-height: 1.78;
}

.page-about .ab-body p:last-child{
  margin-bottom: 0;
}

.page-about .ab-body .note{
  margin-top: 18px;
  padding-left: 14px;
  border-left: 1px solid var(--hair-strong);
  color: var(--stargray);
}

/* 覆盖数字 */
.page-about .ab-stats{
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(20px, 3vw, 30px) 0 clamp(18px, 2.6vw, 26px);
  background: var(--hair);
  border: 1px solid var(--hair);
}

.page-about .ab-stat{
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: clamp(14px, 2.4vw, 26px);
  background: var(--void);
}

.page-about .ab-stat-n{
  font-family: var(--font-mono);
  font-size: clamp(1.4rem, 3vw, 2.1rem);
  font-weight: 600;
  letter-spacing: 0.02em;
  line-height: 1;
  color: var(--gold);
}

.page-about .ab-stat-t{
  font-size: var(--fs-12);
  letter-spacing: 0.06em;
  color: var(--stargray);
}

/* 轨道刻度装饰 */
.page-about .ab-orbit{
  position: relative;
  height: 56px;
  margin: 0 0 clamp(16px, 2.4vw, 24px);
}

.page-about .ab-orbit::before{
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 50%;
  height: 14px;
  transform: translateY(-50%);
  background-image: repeating-linear-gradient(
    to right,
    var(--hair-strong) 0 1px,
    transparent 1px 22px
  );
  background-repeat: repeat-x;
  opacity: 0.9;
}

.page-about .ab-orbit::after{
  content: "";
  position: absolute;
  right: 0;
  top: 50%;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--electric);
  box-shadow: var(--glow-cyan);
  transform: translate(50%, -50%);
}

/* 团队构成 */
.page-about .ab-crew{
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(18px, 2.6vw, 28px) 0 clamp(22px, 3.2vw, 32px);
  background: var(--hair);
  border: 1px solid var(--hair);
}

.page-about .ab-crew-item{
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: clamp(14px, 2.2vw, 22px);
  background: var(--night);
}

.page-about .ab-crew-n{
  font-size: clamp(1.4rem, 2.8vw, 2rem);
  font-weight: 600;
  line-height: 1;
}

.page-about .ab-crew-t{
  font-size: var(--fs-14);
  letter-spacing: 0.06em;
  color: var(--stargray);
}

/* 工序列表 */
.page-about .ab-flow{
  list-style: none;
  margin: 0 0 clamp(24px, 3.4vw, 36px);
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .ab-flow-item{
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: clamp(12px, 2vw, 20px);
  padding: clamp(14px, 2.2vw, 22px);
  background: var(--night);
  border: 1px solid var(--hair);
  border-left: 2px solid var(--nebula);
}

.page-about .ab-flow-idx{
  font-size: var(--fs-14);
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--electric);
  padding-top: 2px;
}

.page-about .ab-flow-text h3{
  margin: 0 0 8px;
  font-size: var(--fs-18);
  letter-spacing: 0.04em;
  color: var(--paper);
}

.page-about .ab-flow-text p{
  margin: 0;
  font-size: var(--fs-16);
  color: var(--stargray);
}

/* 内嵌图 */
.page-about .ab-inline-figure,
.page-about .ab-wide-figure{
  margin: clamp(22px, 3.4vw, 36px) 0 0;
}

.page-about .ab-inline-figure img,
.page-about .ab-wide-figure img{
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid var(--hair);
  background: linear-gradient(150deg, var(--night), var(--void));
}

/* 版本轨道 */
.page-about .ab-timeline{
  display: grid;
  gap: 10px;
  margin-top: clamp(18px, 2.6vw, 28px);
  padding-left: clamp(14px, 2.4vw, 26px);
  border-left: 1px solid var(--hair-strong);
}

.page-about .ab-node{
  position: relative;
}

.page-about .ab-node-btn{
  width: 100%;
  display: flex;
  align-items: baseline;
  gap: clamp(12px, 2vw, 18px);
  padding: clamp(14px, 2vw, 18px);
  background: var(--night);
  border: 1px solid var(--hair);
  color: var(--paper);
  text-align: left;
  cursor: pointer;
  transition: border-color 180ms ease, background-color 180ms ease;
}

.page-about .ab-node-btn:hover{
  border-color: var(--hair-strong);
}

.page-about .ab-node-btn[aria-expanded="true"]{
  border-color: var(--electric);
  background: linear-gradient(150deg, var(--night), var(--void));
}

.page-about .ab-node-year{
  font-size: var(--fs-16);
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--gold);
  flex: 0 0 auto;
}

.page-about .ab-node-name{
  flex: 1 1 auto;
  min-width: 0;
  font-size: var(--fs-18);
  letter-spacing: 0.04em;
}

.page-about .ab-node .expander-panel{
  padding: 4px clamp(14px, 2vw, 18px) 16px;
  border-left: 1px solid var(--hair);
  margin-left: 1px;
}

.page-about .ab-node .expander-panel p{
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.78;
  color: var(--stargray);
  max-width: 62ch;
}

/* 下一步入口 */
.page-about .ab-next{
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin-top: clamp(20px, 3vw, 30px);
}

.page-about .ab-next-card{
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: clamp(16px, 2.4vw, 24px);
  background: linear-gradient(155deg, var(--night), var(--void));
  border: 1px solid var(--hair);
  color: var(--paper);
  text-decoration: none;
  transition: border-color 180ms ease, transform 180ms ease;
}

.page-about .ab-next-card:hover,
.page-about .ab-next-card:focus-visible{
  border-color: var(--electric);
  transform: translateY(-2px);
}

.page-about .ab-next-k{
  font-size: var(--fs-12);
  letter-spacing: 0.1em;
  color: var(--electric);
}

.page-about .ab-next-t{
  font-size: var(--fs-18);
  letter-spacing: 0.04em;
  color: var(--paper);
}

.page-about .ab-next-d{
  font-size: var(--fs-14);
  line-height: 1.7;
  color: var(--stargray);
}

/* 桌面布局 */
@media (min-width: 880px){
  .page-about .ab-sec{
    grid-template-columns: var(--ab-rail) minmax(0, 1fr);
    gap: clamp(28px, 4vw, 64px);
  }

  .page-about .ab-rail{
    position: sticky;
    top: calc(var(--topbar-h) + 28px);
    align-self: start;
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
    padding-left: 16px;
    border-left: 1px solid var(--hair-strong);
  }

  .page-about .ab-rail::before{
    content: "";
    position: absolute;
    left: -3.5px;
    top: 4px;
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--electric);
    box-shadow: var(--glow-cyan);
  }

  .page-about .ab-rail-label{
    letter-spacing: 0.16em;
  }

  .page-about .ab-stats{
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .ab-next{
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 960px){
  .page-about .ab-hero-inner{
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
    gap: clamp(32px, 4.4vw, 68px);
  }
}

@media (min-width: 1180px){
  .page-about .ab-crew{
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce){
  .page-about .ab-node-btn,
  .page-about .ab-next-card{
    transition: none;
  }
  .page-about .ab-next-card:hover,
  .page-about .ab-next-card:focus-visible{
    transform: none;
  }
}
<<<END>>>