.page-about {
  --about-rule: rgba(201, 194, 182, .22);
  --about-rule-soft: rgba(201, 194, 182, .1);
  --about-rule-ink: rgba(22, 19, 17, .16);
  background: var(--ink);
  color: var(--chalk);
}

/* ---------- 阅读进度细线 ---------- */
.page-about .progress-rail {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  z-index: 90;
  background: var(--about-rule-soft);
  pointer-events: none;
}
.page-about .progress-rail__bar {
  display: block;
  height: 100%;
  width: 0;
  background: var(--cyan);
  transition: width .12s linear;
}

/* ---------- 面包屑 ---------- */
.page-about .crumbs {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
  padding-top: 22px;
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: .04em;
  color: var(--warm);
}
.page-about .crumbs__link {
  color: var(--warm);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .18s var(--ease), border-color .18s var(--ease);
}
.page-about .crumbs__link:hover,
.page-about .crumbs__link:focus-visible {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}
.page-about .crumbs__sep { color: rgba(201, 194, 182, .42); }
.page-about .crumbs__item { color: var(--gold); }

/* ---------- 通用章节节奏 ---------- */
.page-about .section {
  padding-block: clamp(42px, 6vw, 92px);
}
.page-about .section--tight {
  padding-block: clamp(28px, 4vw, 56px);
}
.page-about .section--cream {
  background: var(--cream);
  color: var(--text-ink);
}
.page-about .section--cream .h2,
.page-about .section--cream .h3 {
  color: var(--text-ink);
}
.page-about .section--cream .para,
.page-about .section--cream .about-team__desc,
.page-about .section--cream .about-miles__desc {
  color: var(--ink-soft);
}
.page-about .section--cream .eyebrow {
  color: var(--gold-ink);
}
.page-about .h2 {
  margin: 12px 0 0;
  max-width: 26ch;
}
.page-about .para {
  margin: 18px 0 0;
  max-width: 34ch;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  background: var(--ink-deep);
  padding-block: clamp(38px, 5vw, 68px) clamp(48px, 8vw, 108px);
  border-bottom: 1px solid var(--line-gold);
}
.page-about .about-hero::after {
  content: "";
  position: absolute;
  top: -22%;
  right: -16%;
  width: 64%;
  height: 152%;
  background: linear-gradient(155deg, rgba(200, 162, 74, .17), rgba(53, 224, 201, .05) 62%, rgba(11, 27, 43, 0) 100%);
  clip-path: polygon(30% 0, 100% 0, 100% 100%, 0 100%);
  pointer-events: none;
}
.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3.6vw, 42px);
}
.page-about .about-hero__year {
  display: flex;
  align-items: baseline;
  gap: .12em;
  font-size: clamp(42px, 11vw, 88px);
  line-height: .9;
  font-weight: 700;
  letter-spacing: .01em;
  color: var(--gold);
}
.page-about .about-hero__arrow {
  font-size: .5em;
  color: var(--gold-light);
  transform: translateY(-.22em);
}
.page-about .about-hero__title {
  margin: 14px 0 0;
  max-width: 20ch;
}
.page-about .about-hero__lede {
  margin: 20px 0 0;
  max-width: 42ch;
  color: var(--on-ink-soft);
}

/* ---------- 规模数字带 ---------- */
.page-about .about-figures {
  background: var(--ink-deep);
  border-bottom: 1px solid var(--about-rule);
}
.page-about .about-figures__list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  background: var(--about-rule);
  border-block: 1px solid var(--about-rule);
}
.page-about .about-figures__item {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: clamp(20px, 2.8vw, 32px) clamp(14px, 1.8vw, 24px);
  background: var(--ink-deep);
}
.page-about .about-figures__num {
  font-size: clamp(22px, 2.6vw, 30px);
  font-weight: 700;
  line-height: 1.1;
  color: var(--gold);
  letter-spacing: .02em;
}
.page-about .about-figures__label {
  font-size: var(--fs-13);
  line-height: 1.7;
  color: var(--warm);
  max-width: 24ch;
}

/* ---------- 8 / 4 不对称分栏 ---------- */
.page-about .about-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 4vw, 56px);
}
.page-about .about-split__main { min-width: 0; }
.page-about .about-split__aside { min-width: 0; }

/* ---------- 批注 ---------- */
.page-about .about-note {
  border-left: 1px solid var(--line-gold);
  padding-left: clamp(14px, 1.8vw, 22px);
  font-size: var(--fs-13);
  line-height: 1.8;
  color: var(--warm);
}
.page-about .about-note p {
  margin: 0;
  max-width: 30ch;
}
.page-about .about-note__k {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: .08em;
  color: var(--gold);
}
.page-about .section--cream .about-note {
  border-left-color: var(--gold);
  color: var(--ink-soft);
}
.page-about .section--cream .about-note__k { color: var(--gold-ink); }

/* ---------- 时间带 ---------- */
.page-about .about-track {
  background: var(--ink);
  border-block: 1px solid var(--about-rule);
}
.page-about .about-track__title { margin-bottom: clamp(6px, 1vw, 14px); }

.page-about .about-band {
  margin: clamp(26px, 3.4vw, 44px) 0 0;
}
.page-about .about-band img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  border-block: 1px solid var(--line-gold);
}
.page-about .about-band__cap {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 12px var(--gutter) 0;
  font-size: var(--fs-13);
  color: var(--warm);
}

.page-about .about-timeline {
  display: flex;
  flex-wrap: wrap;
  gap: 2px;
  margin: clamp(26px, 3.4vw, 42px) 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line-gold);
  border-bottom: 1px solid var(--about-rule);
}
.page-about .about-timeline__block {
  flex: 1 1 200px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: clamp(20px, 2.8vw, 34px) clamp(16px, 1.8vw, 26px);
  background: var(--ink-deep);
  border-left: 1px solid var(--about-rule);
  transition: background .22s var(--ease), border-color .22s var(--ease);
}
.page-about .about-timeline__block:first-child { border-left: 0; }
.page-about .about-timeline__block:nth-child(1) { flex-grow: 1; }
.page-about .about-timeline__block:nth-child(2) { flex-grow: 1.35; }
.page-about .about-timeline__block:nth-child(3) { flex-grow: 1.15; }
.page-about .about-timeline__block:nth-child(4) { flex-grow: 1.5; }
.page-about .about-timeline__block:hover,
.page-about .about-timeline__block:focus-within {
  background: rgba(200, 162, 74, .09);
  border-left-color: var(--gold);
}
.page-about .about-timeline__year {
  font-size: var(--fs-15);
  letter-spacing: .08em;
  color: var(--gold);
}
.page-about .about-timeline__name {
  font-family: var(--font-head);
  font-size: var(--fs-24);
  font-weight: 700;
  letter-spacing: .02em;
  color: var(--chalk);
}
.page-about .about-timeline__desc {
  font-size: var(--fs-15);
  line-height: 1.75;
  color: var(--on-ink-soft);
}

/* ---------- 团队与分工 ---------- */
.page-about .about-team__list {
  display: grid;
  gap: 1px;
  margin: clamp(24px, 3vw, 38px) 0 0;
  padding: 0;
  list-style: none;
  background: var(--about-rule-ink);
  border-block: 1px solid var(--about-rule-ink);
}
.page-about .about-team__item {
  display: grid;
  grid-template-columns: clamp(38px, 5vw, 62px) minmax(0, 1fr);
  column-gap: clamp(14px, 2vw, 24px);
  padding-block: clamp(18px, 2.4vw, 26px);
  background: var(--cream);
}
.page-about .about-team__num {
  font-size: clamp(20px, 2.4vw, 26px);
  font-weight: 700;
  line-height: 1.1;
  color: var(--gold-ink);
}
.page-about .about-team__name {
  margin: 0;
  font-size: var(--fs-20);
}
.page-about .about-team__desc {
  margin: 8px 0 0;
  font-size: var(--fs-15);
  line-height: 1.75;
  color: var(--ink-soft);
  max-width: 40ch;
}

/* ---------- 图片容器 ---------- */
.page-about .about-figure {
  margin: 0;
  border: 1px solid var(--line-gold);
  background: var(--ink-deep);
}
.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}
.page-about .about-figure__cap {
  padding: 10px 14px;
  font-size: var(--fs-13);
  line-height: 1.6;
  color: var(--warm);
  border-top: 1px solid var(--line);
}
.page-about .section--cream .about-figure {
  border-color: var(--gold);
  background: var(--cream);
}
.page-about .section--cream .about-figure__cap {
  color: var(--ink-soft);
  border-top-color: var(--about-rule-ink);
}
.page-about .about-figure--tall img { object-position: center top; }

/* ---------- 规范手册 ---------- */
.page-about .about-manual {
  background: var(--ink-deep);
  border-block: 1px solid var(--about-rule);
}
.page-about .about-manual__dl {
  margin: clamp(24px, 3vw, 38px) 0 0;
  border-top: 1px solid var(--line-gold);
}
.page-about .about-manual__row {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 6px;
  padding-block: clamp(16px, 2vw, 22px);
  border-bottom: 1px solid var(--about-rule);
}
.page-about .about-manual__term {
  font-family: var(--font-head);
  font-size: var(--fs-17);
  font-weight: 700;
  letter-spacing: .04em;
  color: var(--gold);
}
.page-about .about-manual__def {
  margin: 0;
  font-size: var(--fs-15);
  line-height: 1.8;
  color: var(--on-ink-soft);
  max-width: 42ch;
}

/* ---------- 四件可核对的事 ---------- */
.page-about .about-check__list {
  margin: clamp(26px, 3.4vw, 44px) 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--about-rule-ink);
}
.page-about .about-check__item {
  display: grid;
  grid-template-columns: clamp(46px, 8vw, 96px) minmax(0, 1fr);
  gap: clamp(14px, 2.4vw, 34px);
  align-items: start;
  padding-block: clamp(22px, 3vw, 34px);
  border-bottom: 1px solid var(--about-rule-ink);
}
.page-about .about-check__num {
  font-size: clamp(38px, 6.4vw, 72px);
  font-weight: 700;
  line-height: .9;
  color: var(--gold-ink);
}
.page-about .about-check__body .h3 {
  margin: 0;
  font-size: var(--fs-20);
}
.page-about .about-check__body .para {
  margin-top: 12px;
  max-width: 48ch;
}

/* ---------- 自有规范清单 ---------- */
.page-about .about-miles {
  background: var(--ink);
}
.page-about .about-miles__list {
  margin: clamp(24px, 3vw, 38px) 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--about-rule);
}
.page-about .about-miles__item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 6px;
  padding-block: clamp(16px, 2.2vw, 24px);
  border-bottom: 1px solid var(--about-rule);
}
.page-about .about-miles__ver {
  font-size: var(--fs-15);
  font-weight: 700;
  letter-spacing: .08em;
  color: var(--gold);
}
.page-about .about-miles__name {
  margin: 0;
  font-family: var(--font-head);
  font-size: var(--fs-17);
  font-weight: 700;
  letter-spacing: .02em;
  color: var(--chalk);
}
.page-about .about-miles__desc {
  margin: 6px 0 0;
  font-size: var(--fs-15);
  line-height: 1.75;
  color: var(--on-ink-soft);
  max-width: 42ch;
}

/* ---------- 下游入口 ---------- */
.page-about .about-next {
  background: var(--ink-deep);
  border-top: 1px solid var(--line-gold);
}
.page-about .about-next__title {
  max-width: 24ch;
  margin-bottom: clamp(22px, 3vw, 34px);
}
.page-about .about-next__list {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  background: var(--about-rule);
}
.page-about .about-next__cell { display: flex; }
.page-about .about-next__link {
  display: flex;
  flex-direction: column;
  gap: 10px;
  width: 100%;
  padding: clamp(20px, 2.6vw, 30px);
  background: var(--ink-deep);
  color: var(--chalk);
  text-decoration: none;
  border-top: 2px solid transparent;
  transition: border-color .2s var(--ease), background .2s var(--ease);
}
.page-about .about-next__link:hover,
.page-about .about-next__link:focus-visible {
  border-top-color: var(--cyan);
  background: rgba(53, 224, 201, .06);
}
.page-about .about-next__label {
  font-size: var(--fs-13);
  letter-spacing: .08em;
  color: var(--gold);
}
.page-about .about-next__name {
  font-family: var(--font-head);
  font-size: var(--fs-20);
  font-weight: 700;
  letter-spacing: .02em;
}
.page-about .about-next__desc {
  font-size: var(--fs-15);
  line-height: 1.7;
  color: var(--on-ink-soft);
  max-width: 32ch;
}

/* ---------- 平板与桌面 ---------- */
@media (min-width: 720px) {
  .page-about .about-figures__list {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .about-manual__row {
    grid-template-columns: minmax(110px, 150px) minmax(0, 1fr);
    column-gap: clamp(18px, 2.4vw, 34px);
    align-items: baseline;
  }
  .page-about .about-miles__item {
    grid-template-columns: 92px minmax(0, 1fr);
    column-gap: clamp(16px, 2vw, 26px);
    align-items: baseline;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(170px, 240px) minmax(0, 1fr);
    align-items: end;
  }
  .page-about .about-hero__year {
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
  }
  .page-about .about-hero__arrow {
    transform: none;
    font-size: .42em;
    margin-block: .08em;
  }
  .page-about .about-split {
    grid-template-columns: minmax(0, 8fr) minmax(0, 4fr);
    align-items: start;
  }
  .page-about .about-split--rev {
    grid-template-columns: minmax(0, 4fr) minmax(0, 8fr);
  }
  .page-about .about-split__aside {
    position: sticky;
    top: calc(var(--header-h) + 24px);
  }
  .page-about .about-next__list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 1180px) {
  .page-about .about-unit .about-note,
  .page-about .about-team .about-note {
    padding-left: 26px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .progress-rail__bar,
  .page-about .about-timeline__block,
  .page-about .about-next__link,
  .page-about .crumbs__link {
    transition: none;
  }
}