.page-about {
  --about-rule: rgba(201,163,86,.30);
  --about-ink-line: rgba(14,42,36,.14);
  --about-soft: rgba(14,42,36,.055);
  background: var(--ink);
  color: var(--paper);
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: calc(var(--header-h) + clamp(44px, 8vw, 92px)) 0 clamp(34px, 6vw, 62px);
  background:
    radial-gradient(120% 92% at 84% 0%, rgba(31,74,61,.88) 0%, rgba(14,42,36,0) 62%),
    var(--ink);
  overflow: hidden;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: min(46%, 620px);
  height: 1px;
  background: linear-gradient(90deg, var(--gold), rgba(201,163,86,0));
}

.page-about .about-hero__kicker {
  margin: 22px 0 0;
  color: var(--gold);
  letter-spacing: .22em;
}

.page-about .about-hero__title {
  margin: 16px 0 0;
  font-family: var(--serif);
  font-size: clamp(34px, 7vw, 92px);
  font-weight: 600;
  line-height: 1.08;
  letter-spacing: -.01em;
  color: var(--paper);
  max-width: 16em;
}

.page-about .about-hero__title em {
  display: block;
  font-style: normal;
  color: var(--gold-lit);
  background: var(--gold-grad);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.page-about .about-hero__lede {
  margin: 24px 0 0;
  max-width: 34em;
  color: rgba(244,239,230,.78);
}

.page-about .about-facts {
  list-style: none;
  margin: clamp(34px, 5vw, 56px) 0 0;
  padding: 0;
  display: grid;
  gap: 20px;
}

.page-about .about-fact {
  display: grid;
  gap: 4px;
  padding-top: 14px;
  border-top: 1px solid var(--about-rule);
}

.page-about .about-fact__num {
  font-family: var(--mono);
  font-size: clamp(22px, 3.4vw, 34px);
  letter-spacing: .06em;
  color: var(--gold-lit);
  line-height: 1.1;
}

.page-about .about-fact__text {
  font-size: 13px;
  color: rgba(244,239,230,.66);
  letter-spacing: .02em;
}

.page-about .about-hero__figure {
  margin: 0;
  border-top: 1px solid var(--about-rule);
  border-bottom: 1px solid rgba(244,239,230,.10);
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: clamp(220px, 42vw, 520px);
  object-fit: cover;
  opacity: .88;
}

/* ---------- 阅读主体区 ---------- */
.page-about .about-body-area {
  background: var(--paper);
  color: var(--ink);
  padding: clamp(48px, 7vw, 96px) 0 clamp(56px, 8vw, 110px);
}

.page-about .split {
  align-items: start;
  gap: clamp(26px, 4vw, 64px);
}

.page-about .about-rail {
  border-top: 1px solid var(--about-ink-line);
  padding-top: 14px;
}

.page-about .rail__title {
  margin: 0 0 12px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .22em;
  color: var(--stone);
}

.page-about .rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .rail__link {
  display: flex;
  gap: 10px;
  align-items: baseline;
  padding: 9px 10px 9px 14px;
  font-size: 14px;
  line-height: 1.5;
  color: var(--stone);
  text-decoration: none;
  border-left: 1px solid var(--about-ink-line);
  transition: color .25s var(--ease), border-color .25s var(--ease), background .25s var(--ease);
}

.page-about .rail__link:hover,
.page-about .rail__link:focus-visible {
  color: var(--ink);
  border-left-color: var(--gold-lit);
  background: rgba(201,163,86,.10);
}

.page-about .rail__link[aria-current="true"] {
  color: var(--ink);
  border-left-color: var(--gold);
  background: rgba(201,163,86,.14);
}

.page-about .rail__count {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--gold);
}

/* ---------- 章节 ---------- */
.page-about .about-section {
  padding-bottom: clamp(46px, 6vw, 78px);
}

.page-about .about-section + .about-section {
  border-top: 1px solid var(--about-ink-line);
  padding-top: clamp(38px, 5vw, 64px);
}

.page-about .about-section__head {
  display: flex;
  gap: 14px;
  align-items: baseline;
  margin-bottom: 22px;
}

.page-about .about-section__num {
  font-family: var(--mono);
  font-size: 13px;
  letter-spacing: .18em;
  color: var(--gold);
  flex: none;
}

.page-about .about-section__head .h2 {
  margin: 0;
  font-family: var(--serif);
  font-size: clamp(23px, 3.2vw, 38px);
  line-height: 1.22;
  letter-spacing: -.01em;
  color: var(--ink);
}

.page-about .about-grid {
  display: grid;
  gap: clamp(22px, 3vw, 44px);
}

.page-about .about-body p {
  color: rgba(14,42,36,.80);
  line-height: 1.9;
}

.page-about .about-body p + p {
  margin-top: 16px;
}

.page-about .about-drop::first-letter {
  float: left;
  font-family: var(--serif);
  font-size: 58px;
  line-height: .88;
  padding: 8px 12px 0 0;
  color: var(--green);
}

.page-about .about-note {
  border-top: 1px solid var(--gold);
  padding-top: 12px;
  font-size: 13px;
  line-height: 1.85;
  color: var(--stone);
}

.page-about .about-note p {
  margin: 0;
}

.page-about .about-note__label {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--clay);
  margin-bottom: 6px;
}

/* 引用块 */
.page-about .about-quote {
  margin: 28px 0 0;
  padding: 22px 24px;
  border: none;
  border-left: 2px solid var(--gold);
  background: rgba(201,163,86,.09);
  clip-path: var(--clip-cut-sm);
  cursor: default;
  transition: background .3s var(--ease);
}

.page-about .about-quote:hover,
.page-about .about-quote:focus {
  background: rgba(201,163,86,.15);
  outline: none;
}

.page-about .about-quote__lead {
  margin: 0;
  font-family: var(--serif);
  font-size: clamp(17px, 2vw, 21px);
  line-height: 1.68;
  color: var(--green);
}

.page-about .about-quote__more {
  margin: 0;
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  font-size: 14px;
  line-height: 1.85;
  color: var(--stone);
  transition: max-height .38s var(--ease), opacity .3s var(--ease), margin-top .3s var(--ease);
}

.page-about .about-quote:hover .about-quote__more,
.page-about .about-quote:focus .about-quote__more,
.page-about .about-quote:focus-within .about-quote__more {
  max-height: 200px;
  opacity: 1;
  margin-top: 12px;
}

/* 图片容器 */
.page-about .media-frame {
  margin: 0;
  border: 1px solid var(--about-ink-line);
  background: var(--about-soft);
  overflow: hidden;
  clip-path: var(--clip-cut-sm);
}

.page-about .media-frame img {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .media-frame__caption {
  padding: 10px 14px;
  font-size: 12px;
  line-height: 1.7;
  color: var(--stone);
  border-top: 1px solid var(--about-ink-line);
  background: rgba(244,239,230,.6);
}

.page-about .about-figure--square img {
  aspect-ratio: 1 / 1;
  object-fit: cover;
}

/* 世代分层 */
.page-about .layer-stack {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .layer {
  display: grid;
  gap: 6px;
  padding: 16px 18px;
  background: var(--about-soft);
  border-left: 2px solid var(--green);
  clip-path: var(--clip-cut-sm);
}

.page-about .layer__tag {
  font-family: var(--mono);
  font-size: 14px;
  letter-spacing: .08em;
  color: var(--gold);
}

.page-about .layer__title {
  margin: 0;
  font-family: var(--serif);
  font-size: 16px;
  font-weight: 600;
  color: var(--ink);
}

.page-about .layer__desc {
  margin: 5px 0 0;
  font-size: 14px;
  line-height: 1.82;
  color: var(--stone);
}

/* 校验工序 */
.page-about .about-steps-lead {
  margin: 30px 0 0;
  font-size: 14px;
  color: var(--stone);
}

.page-about .about-steps {
  list-style: none;
  margin: 16px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
  counter-reset: ab-step;
}

.page-about .about-steps .step {
  position: relative;
  padding: 18px 18px 18px 22px;
  background: rgba(244,239,230,.7);
  border: 1px solid var(--about-ink-line);
  border-top: 2px solid var(--gold);
  clip-path: var(--clip-cut-sm);
}

.page-about .about-steps .step__title {
  margin: 0 0 6px;
  font-family: var(--serif);
  font-size: 16px;
  font-weight: 600;
  color: var(--green);
  letter-spacing: .02em;
}

.page-about .about-steps .step__body {
  margin: 0;
  font-size: 14px;
  line-height: 1.82;
  color: var(--stone);
}

/* 团队数据条 */
.page-about .about-stat-row {
  list-style: none;
  margin: 28px 0 0;
  padding: 22px 0 0;
  border-top: 1px solid var(--about-ink-line);
  display: grid;
  gap: 20px;
}

.page-about .about-stat-row .stat__value {
  display: block;
  font-family: var(--mono);
  font-size: clamp(28px, 4vw, 44px);
  line-height: 1.1;
  letter-spacing: .04em;
  color: var(--green);
}

.page-about .about-stat-row .stat__label {
  display: block;
  margin-top: 6px;
  font-size: 13px;
  color: var(--stone);
}

/* ---------- 历程深色带 ---------- */
.page-about .about-band {
  padding: clamp(26px, 4vw, 46px) clamp(20px, 3vw, 40px);
  background: linear-gradient(160deg, var(--ink-2) 0%, var(--ink) 70%);
  color: var(--paper);
  clip-path: var(--clip-cut);
}

.page-about .about-scale {
  display: block;
  width: 100%;
  height: 26px;
  margin-bottom: 6px;
}

.page-about .about-scale line {
  stroke: rgba(201,163,86,.42);
  stroke-width: 1;
}

.page-about .about-scale rect {
  fill: var(--gold);
}

.page-about .timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .timeline__node {
  position: relative;
  padding: 26px 0 6px;
  border-top: 1px solid rgba(201,163,86,.28);
}

.page-about .timeline__node::after {
  content: "";
  position: absolute;
  top: -5px;
  left: 0;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--gold-lit);
  box-shadow: 0 0 0 4px rgba(230,200,123,.14);
}

.page-about .timeline__phase {
  margin: 0;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--gold-lit);
}

.page-about .timeline__title {
  margin: 10px 0 0;
  font-family: var(--serif);
  font-size: clamp(17px, 2vw, 21px);
  font-weight: 600;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .timeline__body {
  margin: 8px 0 0;
  font-size: 14px;
  line-height: 1.85;
  color: rgba(244,239,230,.72);
}

/* ---------- 收尾入口 ---------- */
.page-about .about-links {
  margin-top: 30px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-facts {
    grid-template-columns: repeat(3, 1fr);
    gap: clamp(18px, 3vw, 40px);
  }

  .page-about .about-stat-row {
    grid-template-columns: repeat(2, 1fr);
    gap: 36px;
  }
}

@media (min-width: 760px) {
  .page-about .about-steps {
    grid-template-columns: repeat(3, 1fr);
    gap: 14px;
  }

  .page-about .layer {
    grid-template-columns: 92px minmax(0, 1fr);
    align-items: start;
    gap: 18px;
    padding: 18px 22px;
  }
}

@media (min-width: 860px) {
  .page-about .timeline {
    grid-template-columns: repeat(4, 1fr);
    column-gap: 26px;
  }
}

@media (min-width: 900px) {
  .page-about .about-grid {
    grid-template-columns: minmax(0, 1fr) minmax(200px, 268px);
  }

  .page-about .about-grid--flip {
    grid-template-columns: minmax(240px, 330px) minmax(0, 1fr);
  }
}

@media (min-width: 1024px) {
  .page-about .split__rail {
    position: sticky;
    top: calc(var(--header-h) + 28px);
  }
}

@media (max-width: 759px) {
  .page-about .about-scale {
    display: none;
  }

  .page-about .about-hero__title {
    max-width: none;
  }

  .page-about .about-band {
    clip-path: var(--clip-cut-sm);
  }
}

@media (hover: none) {
  .page-about .about-quote__more {
    max-height: none;
    opacity: 1;
    margin-top: 12px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .rail__link,
  .page-about .about-quote,
  .page-about .about-quote__more {
    transition: none;
  }
}