.page-about {
  --about-rail-w: 208px;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  border-bottom: 1px solid var(--line);
  padding-block: 18px 42px;
  background:
    radial-gradient(1100px 400px at 84% -14%, rgba(15, 111, 108, .11), transparent 62%),
    radial-gradient(700px 340px at 4% -4%, rgba(200, 155, 74, .11), transparent 66%);
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 30px;
  margin-top: 22px;
}

.page-about .about-hero__lead .zb-display {
  margin: 14px 0 0;
  font-size: clamp(34px, 8.2vw, 78px);
  font-weight: 200;
  line-height: 1.04;
  letter-spacing: -.02em;
  color: var(--ink);
}

.page-about .about-hero__lead .zb-lead {
  margin-top: 20px;
  max-width: 62ch;
  color: var(--ink-2);
  font-size: 17px;
  line-height: 1.86;
}

.page-about .about-hero__meta {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  background: var(--line);
  border: 1px solid var(--line);
  box-shadow: var(--stack-1);
}

.page-about .about-hero__fact {
  margin: 0;
  padding: 14px 14px 16px;
  background: var(--porcelain);
}

.page-about .about-hero__fact dt {
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--ink-2);
}

.page-about .about-hero__fact dd {
  margin: 8px 0 0;
  display: flex;
  align-items: baseline;
  gap: 4px;
}

.page-about .about-hero__num {
  font-family: var(--mono);
  font-size: clamp(26px, 6.4vw, 36px);
  font-weight: 600;
  line-height: 1.05;
  letter-spacing: -.02em;
  color: var(--jade-deep);
}

/* ---------- 主布局 ---------- */
.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 34px;
  padding-block: 44px 20px;
}

.page-about .about-rail {
  display: none;
}

.page-about .about-rail__title {
  margin: 0 0 10px;
}

.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0 0 0 14px;
  border-left: 1px solid var(--line);
  display: grid;
  gap: 1px;
}

.page-about .about-rail__list a {
  display: flex;
  align-items: baseline;
  gap: 9px;
  padding: 7px 0;
  font-size: 14px;
  line-height: 1.5;
  color: var(--ink-2);
  text-decoration: none;
  transition: color .2s var(--ease), transform .2s var(--ease);
}

.page-about .about-rail__list a:hover,
.page-about .about-rail__list a:focus-visible {
  color: var(--red);
  transform: translateX(2px);
}

.page-about .about-rail__list .zb-mono {
  font-size: 12px;
  color: var(--jade);
}

/* ---------- 时间轴 ---------- */
.page-about .about-stream {
  position: relative;
  display: grid;
  gap: 38px;
  padding-left: 28px;
}

.page-about .about-stream::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 12px;
  bottom: 12px;
  width: 2px;
  background: linear-gradient(180deg,
    var(--red) 0%,
    var(--jade) 22%,
    var(--jade-soft) 64%,
    var(--gold) 100%);
  opacity: .5;
}

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

.page-about .about-node::before {
  content: "";
  position: absolute;
  left: -30px;
  top: 14px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--porcelain);
  border: 2px solid var(--red);
  box-shadow: 0 0 0 4px var(--paper);
  z-index: 2;
}

.page-about .about-node__head {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 12px;
}

.page-about .about-year {
  font-family: var(--mono);
  font-size: 19px;
  font-weight: 700;
  letter-spacing: .02em;
  color: var(--red);
}

.page-about .about-card {
  position: relative;
  overflow: hidden;
  padding: 24px 20px 26px;
}

.page-about .about-card__ghost {
  position: absolute;
  top: -16px;
  right: -4px;
  font-family: var(--mono);
  font-size: clamp(68px, 18vw, 148px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.04em;
  color: var(--jade);
  opacity: .07;
  pointer-events: none;
  user-select: none;
}

.page-about .about-card .zb-h2 {
  max-width: 26ch;
  position: relative;
  z-index: 1;
}

.page-about .about-card p {
  position: relative;
  z-index: 1;
  max-width: 66ch;
  margin-top: 14px;
  font-size: 16px;
  line-height: 1.86;
  color: var(--ink-2);
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  position: relative;
  z-index: 1;
  margin: 22px 0 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border: 1px solid var(--line);
  box-shadow: var(--stack-2);
}

.page-about .about-figure figcaption {
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--ink-2);
}

/* ---------- 城市网点表 ---------- */
.page-about .about-cities {
  list-style: none;
  position: relative;
  z-index: 1;
  margin: 20px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-cities li {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 8px;
  padding: 12px 14px;
  background: var(--porcelain);
  font-size: 14px;
  color: var(--ink-2);
}

.page-about .about-cities b {
  font-family: var(--mono);
  font-size: 22px;
  font-weight: 600;
  color: var(--jade-deep);
}

/* ---------- 筛选项标签 ---------- */
.page-about .about-filters {
  list-style: none;
  position: relative;
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 20px 0 0;
  padding: 0;
}

/* ---------- 版本刻度 ---------- */
.page-about .about-scale {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
  padding: 16px 16px 18px;
  background: var(--mist);
  border: 1px solid var(--line);
}

.page-about .about-scale__track {
  flex: 1 1 150px;
  position: relative;
  height: 6px;
  background: var(--porcelain);
  border: 1px solid var(--line);
}

.page-about .about-scale__fill {
  position: absolute;
  inset: 0 auto 0 0;
  width: 87%;
  background: linear-gradient(90deg, var(--jade) 0%, var(--red) 100%);
}

.page-about .about-scale__mark {
  font-family: var(--mono);
  font-size: 12.5px;
  letter-spacing: .03em;
  color: var(--ink-2);
}

.page-about .about-scale__mark--now {
  color: var(--red);
  font-weight: 700;
}

/* ---------- 关键数据 ---------- */
.page-about .about-node--last {
  padding-bottom: 8px;
}

.page-about .about-stats {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: 22px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-stat {
  padding: 18px 15px 20px;
  background: var(--porcelain);
}

.page-about .about-stat__num {
  display: block;
  font-family: var(--mono);
  font-size: clamp(28px, 7vw, 42px);
  font-weight: 600;
  line-height: 1.06;
  letter-spacing: -.03em;
  color: var(--jade-deep);
}

.page-about .about-stat__num--red {
  color: var(--red);
}

.page-about .about-stat__unit {
  display: block;
  margin-top: 8px;
  font-size: 13px;
  line-height: 1.65;
  color: var(--ink-2);
}

/* ---------- 去向 ---------- */
.page-about .about-next {
  margin-top: 46px;
  padding-block: 44px 56px;
  background: var(--mist);
  border-top: 1px solid var(--line-ink);
}

.page-about .about-next__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: 24px;
}

.page-about .about-next__item {
  display: grid;
  gap: 6px;
  padding: 20px 18px 22px;
  background: var(--porcelain);
  border: 1px solid var(--line-ink);
  box-shadow: var(--stack-1);
  text-decoration: none;
  color: var(--ink);
  transition: transform .24s var(--ease), box-shadow .24s var(--ease), border-color .24s var(--ease);
}

.page-about .about-next__item:hover,
.page-about .about-next__item:focus-visible {
  transform: translateY(-4px);
  box-shadow: var(--stack-3);
  border-color: var(--red);
}

.page-about .about-next__no {
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--red);
}

.page-about .about-next__item strong {
  font-family: var(--sans);
  font-size: 19px;
  font-weight: 700;
  letter-spacing: -.01em;
}

.page-about .about-next__item span:last-child {
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-2);
}

/* ---------- 平板与桌面 ---------- */
@media (min-width: 720px) {
  .page-about .about-next__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

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

@media (min-width: 960px) {
  .page-about .about-hero {
    padding-block: 26px 58px;
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.5fr) minmax(0, .78fr);
    gap: 52px;
    align-items: end;
  }

  .page-about .about-hero__meta {
    box-shadow: var(--stack-2);
  }
}

@media (min-width: 1024px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: 54px;
    padding-block: 62px 28px;
  }

  .page-about .about-rail {
    display: block;
    position: sticky;
    top: calc(var(--header-h) + 26px);
    align-self: start;
  }

  .page-about .about-stream {
    gap: 52px;
    padding-left: 34px;
  }

  .page-about .about-node::before {
    left: -36px;
  }

  .page-about .about-node--wide .about-card {
    padding: 32px 32px 34px;
  }

  .page-about .about-node--narrow .about-card {
    max-width: 640px;
  }

  .page-about .about-card .zb-h2 {
    max-width: 30ch;
  }

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

  .page-about .about-next {
    margin-top: 56px;
    padding-block: 56px 72px;
  }
}

@media (min-width: 1280px) {
  .page-about .about-card p {
    font-size: 17px;
  }
}