.page-about {
  --about-hairline: rgba(200,164,74,.22);
  --about-hairline-soft: rgba(200,164,74,.12);
  --about-text: rgba(244,241,232,.78);
  --about-text-dim: rgba(244,241,232,.62);
  display: block;
  padding-bottom: clamp(48px, 7vw, 96px);
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumbs {
  padding-top: clamp(20px, 3vw, 32px);
}
.page-about .breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: 13px;
  letter-spacing: .04em;
}
.page-about .breadcrumb__link {
  color: var(--muted);
  text-decoration: none;
}
.page-about .breadcrumb__link:hover,
.page-about .breadcrumb__link:focus-visible {
  color: var(--gold-light);
}
.page-about .breadcrumb__sep { color: rgba(157,179,171,.5); }
.page-about .breadcrumb__current { color: var(--cream); }

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: clamp(18px, 3vw, 34px) 0 clamp(36px, 6vw, 76px);
}
.page-about .about-hero__grid {
  display: grid;
  gap: clamp(30px, 5vw, 56px);
  align-items: center;
}
.page-about .about-hero__title {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: clamp(30px, 6.2vw, 50px);
  line-height: 1.24;
  letter-spacing: -.01em;
  color: var(--cream);
  margin: 14px 0 20px;
  max-width: 15em;
}
.page-about .about-hero__lead {
  font-size: clamp(16px, 1.8vw, 18px);
  line-height: 1.9;
  color: var(--about-text);
  margin: 0;
  max-width: 40em;
}
.page-about .about-facts {
  display: flex;
  flex-wrap: wrap;
  gap: 16px 40px;
  list-style: none;
  margin: clamp(26px, 4vw, 36px) 0 0;
  padding: clamp(18px, 3vw, 24px) 0 0;
  border-top: 1px solid var(--about-hairline);
}
.page-about .about-fact {
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.page-about .about-fact__num {
  font-family: var(--font-mono);
  font-size: clamp(22px, 3.4vw, 32px);
  line-height: 1.1;
  color: var(--gold-light);
  letter-spacing: .02em;
}
.page-about .about-fact__label {
  font-size: 13px;
  letter-spacing: .06em;
  color: var(--muted);
}
.page-about .about-hero__visual {
  display: flex;
  justify-content: center;
}
.page-about .about-orbit {
  width: min(100%, 420px);
  height: auto;
  display: block;
}
.page-about .about-orbit__label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .1em;
  fill: var(--muted);
}
.page-about .about-orbit__core {
  font-family: var(--font-mono);
  font-size: 34px;
  fill: var(--gold-light);
}
.page-about .about-orbit__sub {
  font-family: var(--font-sans);
  font-size: 11px;
  letter-spacing: .12em;
  fill: var(--muted);
}

/* ---------- 主体骨架 ---------- */
.page-about .about-body {
  display: grid;
  gap: clamp(24px, 4vw, 34px);
}

/* ---------- 章节索引 ---------- */
.page-about .about-index {
  border-top: 1px solid var(--about-hairline);
  padding-top: 14px;
}
.page-about .chapter-index__title {
  font-size: 12px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0 0 12px;
}
.page-about .about-index__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 10px;
  list-style: none;
  margin: 0;
  padding: 0;
}
.page-about .chapter-index__link {
  display: inline-block;
  padding: 8px 14px;
  min-height: 36px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--about-hairline);
  color: var(--about-text-dim);
  font-size: 13px;
  letter-spacing: .04em;
  text-decoration: none;
  transition: color .3s var(--ease), border-color .3s var(--ease), background-color .3s var(--ease);
}
.page-about .chapter-index__link:hover,
.page-about .chapter-index__link:focus-visible {
  color: var(--gold-light);
  border-color: var(--gold-line-strong);
}
.page-about .chapter-index__link.is-active {
  color: var(--ink-900);
  background: var(--gold);
  border-color: var(--gold);
}

/* ---------- 章节流 ---------- */
.page-about .about-flow {
  display: grid;
  gap: clamp(20px, 3vw, 30px);
  min-width: 0;
}
.page-about .about-section {
  background: var(--ink-700);
  border-radius: var(--radius-lg);
  padding: clamp(24px, 4.5vw, 46px);
  min-width: 0;
}
.page-about .about-section--soft {
  background: rgba(7,26,22,.55);
  border: 1px solid var(--about-hairline-soft);
}

/* ---------- 章节头 ---------- */
.page-about .about-head {
  margin-bottom: clamp(18px, 3vw, 26px);
}
.page-about .about-head .chapter-no {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--gold);
  margin-bottom: 8px;
}
.page-about .about-head__title {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(22px, 3.4vw, 31px);
  line-height: 1.34;
  letter-spacing: -.005em;
  color: var(--cream);
  margin: 0 0 14px;
}
.page-about .about-head .rule {
  display: block;
  height: 1px;
  width: 100%;
  background: linear-gradient(90deg, var(--gold-line-strong), transparent);
}
.page-about .about-lead {
  font-size: clamp(15px, 1.7vw, 17px);
  line-height: 1.85;
  color: var(--about-text);
  margin: 0 0 clamp(20px, 3vw, 28px);
  max-width: 40em;
}
.page-about .about-section p {
  line-height: 1.88;
  color: var(--about-text);
  margin: 0 0 16px;
  max-width: 40em;
}
.page-about .about-section p:last-child { margin-bottom: 0; }
.page-about .about-link {
  color: var(--gold-light);
  text-decoration: none;
  border-bottom: 1px solid var(--gold-line-strong);
  padding-bottom: 1px;
}
.page-about .about-link:hover,
.page-about .about-link:focus-visible {
  color: var(--cream);
  border-bottom-color: var(--cream);
}

/* ---------- 图文交替 ---------- */
.page-about .about-split {
  display: grid;
  gap: clamp(20px, 3vw, 34px);
  align-items: start;
}
.page-about .about-split__media {
  margin: 0;
  border-radius: var(--radius-md);
  overflow: hidden;
}
.page-about .about-split__media img,
.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}
.page-about .media__caption {
  display: block;
  margin-top: 10px;
  font-size: 12.5px;
  letter-spacing: .04em;
  color: var(--muted);
}

/* ---------- 时间轴 ---------- */
.page-about .about-stages {
  display: grid;
  gap: clamp(22px, 3.4vw, 34px);
  margin-top: 6px;
}
.page-about .about-stage {
  position: relative;
  padding-left: 34px;
}
.page-about .about-stage::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 10px;
  bottom: calc(-1 * clamp(22px, 3.4vw, 34px));
  width: 1px;
  background: linear-gradient(180deg, var(--gold-line-strong), var(--about-hairline-soft));
}
.page-about .about-stage:last-child::before { display: none; }
.page-about .about-stage__dot {
  position: absolute;
  left: 0;
  top: 4px;
  width: 15px;
  height: 15px;
  border-radius: 50%;
  border: 1px solid var(--gold);
  background: var(--ink-700);
}
.page-about .about-stage__dot::after {
  content: "";
  position: absolute;
  inset: 3px;
  border-radius: 50%;
  background: var(--gold);
  transition: transform .35s var(--ease);
}
.page-about .about-stage:hover .about-stage__dot::after { transform: scale(1.5); }
.page-about .about-stage__year {
  font-family: var(--font-mono);
  font-size: 15px;
  letter-spacing: .12em;
  color: var(--gold);
  margin: 0 0 8px;
}
.page-about .about-stage__title {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(17px, 2.2vw, 20px);
  line-height: 1.44;
  color: var(--cream);
  margin: 0 0 8px;
}
.page-about .about-stage__body p {
  margin: 0;
  font-size: 15.5px;
}

/* ---------- 班次 ---------- */
.page-about .about-shiftboard {
  margin-top: clamp(26px, 4vw, 38px);
  padding-top: clamp(20px, 3vw, 28px);
  border-top: 1px solid var(--about-hairline);
  display: grid;
  gap: clamp(20px, 3vw, 32px);
}
.page-about .about-shifts {
  width: 100%;
  max-width: 520px;
  height: auto;
  display: block;
}
.page-about .about-shifts__tick {
  font-family: var(--font-mono);
  font-size: 9px;
  fill: var(--muted);
}
.page-about .about-shifts__row {
  font-family: var(--font-sans);
  font-size: 11px;
  fill: var(--about-text-dim);
}
.page-about .about-shifts__cap {
  font-family: var(--font-mono);
  font-size: 9px;
}
.page-about .about-shiftlist {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}
.page-about .about-shiftlist__item {
  display: grid;
  grid-template-columns: minmax(84px, auto) 1fr;
  gap: 14px;
  align-items: baseline;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--about-hairline-soft);
}
.page-about .about-shiftlist__item:last-child { border-bottom: 0; padding-bottom: 0; }
.page-about .about-shiftlist__key {
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--gold-light);
  letter-spacing: .04em;
}
.page-about .about-shiftlist__val {
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--about-text-dim);
}

/* ---------- 档案库 ---------- */
.page-about .about-figure {
  margin: 0 0 clamp(20px, 3vw, 28px);
  border-radius: var(--radius-md);
  overflow: hidden;
}
.page-about .about-archive__lead {
  font-size: clamp(15.5px, 1.8vw, 17px);
  color: var(--cream);
}
.page-about .about-archive__num {
  font-family: var(--font-mono);
  color: var(--gold-light);
  font-size: 1.1em;
  letter-spacing: .02em;
}

/* ---------- 技术项 ---------- */
.page-about .about-tech {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: clamp(16px, 2.6vw, 24px);
}
.page-about .about-tech__item {
  display: grid;
  grid-template-columns: minmax(56px, auto) 1fr;
  gap: 16px;
  align-items: start;
  padding-bottom: clamp(16px, 2.6vw, 24px);
  border-bottom: 1px solid var(--about-hairline-soft);
}
.page-about .about-tech__item:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}
.page-about .about-tech__num {
  font-family: var(--font-mono);
  font-size: clamp(26px, 4vw, 36px);
  line-height: 1.05;
  color: var(--gold);
  letter-spacing: .01em;
}
.page-about .about-tech__title {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(16px, 2vw, 18.5px);
  color: var(--cream);
  margin: 0 0 6px;
  line-height: 1.5;
}
.page-about .about-tech__body p {
  margin: 0;
  font-size: 15px;
}

/* ---------- 四条做法 ---------- */
.page-about .about-promises {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: clamp(18px, 3vw, 26px);
}
.page-about .about-promise {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 16px;
  align-items: start;
}
.page-about .about-promise__no {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .1em;
  color: var(--wine);
  background: rgba(244,241,232,.08);
  border: 1px solid var(--about-hairline);
  border-radius: var(--radius-sm);
  padding: 6px 10px;
  line-height: 1;
}
.page-about .about-promise__title {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(16.5px, 2.1vw, 19px);
  color: var(--cream);
  margin: 0 0 8px;
  line-height: 1.5;
}
.page-about .about-promise__body p {
  margin: 0;
  font-size: 15px;
}

/* ---------- 结尾引导 ---------- */
.page-about .about-cta {
  margin-top: clamp(28px, 4vw, 40px);
  padding-top: clamp(22px, 3vw, 30px);
  border-top: 1px solid var(--about-hairline);
  display: grid;
  gap: 18px;
}
.page-about .about-cta__text {
  font-size: clamp(15.5px, 1.8vw, 17px);
  color: var(--cream);
  margin: 0;
}
.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 平板与桌面 ---------- */
@media (min-width: 720px) {
  .page-about .about-split {
    grid-template-columns: 1fr 1fr;
    gap: clamp(24px, 4vw, 42px);
  }
  .page-about .about-split--reverse .about-split__media { order: 0; }
  .page-about .about-split--reverse .about-split__text { order: 1; }
  .page-about .about-shiftboard {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: center;
  }
  .page-about .about-cta {
    grid-template-columns: 1fr auto;
    align-items: center;
  }
}

@media (min-width: 860px) {
  .page-about .about-stage {
    display: grid;
    grid-template-columns: 96px minmax(0, 1fr);
    gap: 0 22px;
    padding-left: 34px;
  }
  .page-about .about-stage__year {
    grid-column: 1;
    margin: 2px 0 0;
  }
  .page-about .about-stage__body { grid-column: 2; }
}

@media (min-width: 1024px) {
  .page-about .about-hero__grid {
    grid-template-columns: 5fr 7fr;
    gap: clamp(40px, 5vw, 64px);
  }
  .page-about .about-body {
    grid-template-columns: 220px minmax(0, 1fr);
    gap: clamp(34px, 4vw, 56px);
    align-items: start;
  }
  .page-about .about-index {
    position: sticky;
    top: 108px;
    border-top: 0;
    padding-top: 0;
  }
  .page-about .about-index__list {
    flex-direction: column;
    align-items: stretch;
    gap: 6px;
  }
  .page-about .chapter-index__link {
    display: block;
    border-radius: var(--radius-sm);
    border-color: transparent;
    border-left: 2px solid var(--about-hairline);
    background: transparent;
  }
  .page-about .chapter-index__link:hover,
  .page-about .chapter-index__link:focus-visible {
    border-left-color: var(--gold);
    background: rgba(200,164,74,.06);
  }
  .page-about .chapter-index__link.is-active {
    background: rgba(200,164,74,.1);
    border-color: transparent;
    border-left-color: var(--gold);
    color: var(--gold-light);
  }
}

@media (min-width: 1200px) {
  .page-about .about-hero__grid { grid-template-columns: 5fr 7fr; }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .chapter-index__link,
  .page-about .about-stage__dot::after {
    transition: none;
  }
  .page-about .about-stage:hover .about-stage__dot::after { transform: none; }
}