.page-about {
  --about-body: #22352E;
  --about-dim: rgba(201, 214, 208, 0.62);
  --about-line-ink: rgba(11, 31, 25, 0.16);
  --about-line-night: rgba(201, 214, 208, 0.16);
  display: block;
  background: var(--ink);
  padding-bottom: 64px;
}

.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 24px;
  padding-top: 20px;
  padding-bottom: 8px;
}

/* ---------- 左侧年份索引 ---------- */

.page-about .about-rail__sticky {
  display: block;
}

.page-about .about-rail__label {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.18em;
  color: var(--neon);
  text-transform: uppercase;
}

.page-about .about-rail__years {
  list-style: none;
  margin: 0;
  padding: 0 0 6px;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

.page-about .about-rail__years > li {
  flex: none;
}

.page-about .about-year {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 108px;
  padding: 9px 12px;
  border: 1px solid var(--about-line-night);
  border-left: 2px solid var(--about-line-night);
  color: var(--cool);
  text-decoration: none;
  transition: border-color 0.18s ease, color 0.18s ease, background-color 0.18s ease;
}

.page-about .about-year__num {
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--paper);
}

.page-about .about-year__note {
  font-size: 11px;
  line-height: 1.45;
  letter-spacing: 0.02em;
  color: var(--about-dim);
}

.page-about .about-year:hover,
.page-about .about-year:focus-visible {
  border-color: var(--neon);
  background: rgba(59, 240, 196, 0.08);
}

.page-about .about-year:hover .about-year__num,
.page-about .about-year:focus-visible .about-year__num {
  color: var(--neon);
}

.page-about .about-rail__foot {
  margin: 14px 0 0;
  font-size: 12px;
  line-height: 1.6;
  letter-spacing: 0.04em;
  color: var(--about-dim);
}

/* ---------- 右侧主体面板 ---------- */

.page-about .about-flow {
  min-width: 0;
  background: var(--paper);
  color: var(--ink);
  padding: 26px 20px 40px;
  border: 2px solid var(--night);
  box-shadow: var(--shadow-hard-soft);
}

.page-about .about-hero .breadcrumbs {
  margin-bottom: 18px;
}

.page-about .about-hero__title {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(29px, 5vw, 48px);
  line-height: 1.16;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.page-about .about-hero__lede {
  margin: 16px 0 0;
  max-width: 62ch;
  font-size: 16.5px;
  line-height: 1.72;
  color: var(--about-body);
}

.page-about .about-hero .eyebrow {
  display: inline-block;
  margin-top: 4px;
}

/* ---------- 图片 ---------- */

.page-about .about-figure {
  margin: 24px 0 0;
  border: 2px solid var(--night);
  background: var(--night);
  overflow: hidden;
}

.page-about .about-figure--hero {
  margin-top: 26px;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  aspect-ratio: 16 / 9;
}

.page-about .about-figure--hero img {
  aspect-ratio: 16 / 9;
}

.page-about .about-figure figcaption {
  padding: 10px 12px;
  font-size: 12px;
  line-height: 1.6;
  letter-spacing: 0.04em;
  color: var(--cool);
  background: var(--night);
  border-top: 1px solid var(--about-line-night);
}

/* ---------- 区块与标题 ---------- */

.page-about .about-sec {
  margin-top: 48px;
}

.page-about .about-head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--ink);
  margin-bottom: 20px;
}

.page-about .about-idx {
  flex: none;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
  line-height: 1.4;
  padding: 3px 7px;
  color: var(--neon);
  background: var(--ink);
}

.page-about .about-head h2 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(21px, 3vw, 30px);
  line-height: 1.26;
  letter-spacing: -0.005em;
  color: var(--ink);
}

.page-about .about-prose {
  max-width: 64ch;
}

.page-about .about-prose p {
  margin: 0 0 14px;
  font-size: 16px;
  line-height: 1.74;
  color: var(--about-body);
}

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

/* ---------- 四步流程 ---------- */

.page-about .about-steps {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .flow-step {
  position: relative;
  padding: 18px 16px 16px;
  background: var(--paper);
  border: 2px solid var(--ink);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.page-about .flow-step:hover,
.page-about .flow-step:focus-within,
.page-about .flow-step:focus {
  transform: translate(-3px, -3px);
  box-shadow: var(--shadow-hard-soft);
  outline: none;
}

.page-about .flow-step:focus-visible {
  outline: 2px solid var(--neon);
  outline-offset: 3px;
}

.page-about .flow-step__no {
  display: inline-block;
  margin-bottom: 10px;
  padding: 2px 7px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--ink);
  background: var(--neon);
}

.page-about .flow-step__title {
  margin: 0 0 8px;
  font-family: var(--font-body);
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 0.01em;
  color: var(--ink);
}

.page-about .flow-step__base {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--about-body);
}

.page-about .flow-step__more {
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  margin: 0;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--mid);
  transition: max-height 0.26s ease, opacity 0.2s ease, margin-top 0.26s ease;
}

.page-about .flow-step:hover .flow-step__more,
.page-about .flow-step:focus-within .flow-step__more {
  max-height: 140px;
  opacity: 1;
  margin-top: 9px;
}

/* ---------- 深色面板：团队 ---------- */

.page-about .about-ink {
  background: var(--ink);
  border: 2px solid var(--night);
  padding: 26px 20px 30px;
}

.page-about .about-head--ink {
  border-bottom-color: var(--neon);
}

.page-about .about-head--ink h2 {
  color: var(--paper);
}

.page-about .about-head--ink .about-idx {
  color: var(--ink);
  background: var(--neon);
}

.page-about .about-ink__lede {
  margin: 0;
  max-width: 58ch;
  font-size: 16px;
  line-height: 1.72;
  color: var(--cool);
}

.page-about .about-stat-row {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin-top: 22px;
}

.page-about .about-stat {
  padding: 14px 12px;
  border: 1px solid var(--about-line-night);
  border-left: 2px solid var(--neon);
  background: rgba(5, 10, 9, 0.5);
}

.page-about .about-stat__value {
  display: block;
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 700;
  line-height: 1.05;
  letter-spacing: 0.01em;
  color: var(--neon);
}

.page-about .about-stat__label {
  display: block;
  margin-top: 6px;
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--about-dim);
}

.page-about .about-ink__note {
  margin: 20px 0 0;
  max-width: 60ch;
  font-size: 14px;
  line-height: 1.72;
  color: var(--cool);
  padding-top: 16px;
  border-top: 1px solid var(--about-line-night);
}

/* ---------- 筛选 ---------- */

.page-about .about-filters {
  margin: 0 0 22px;
}

.page-about .about-filter-btn {
  border-color: var(--ink);
  color: var(--ink);
}

/* ---------- 年份时间轴 ---------- */

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

.page-about .track-card {
  position: relative;
  padding: 0 0 24px 22px;
  border-left: 2px solid var(--about-line-ink);
}

.page-about .track-card::before {
  content: "";
  position: absolute;
  left: -7px;
  top: 6px;
  width: 8px;
  height: 8px;
  background: var(--ink);
  box-shadow: 0 0 0 2px var(--paper);
}

.page-about .track-card:last-child {
  border-left-color: transparent;
  padding-bottom: 0;
}

.page-about .track-card__head {
  display: flex;
  align-items: center;
  gap: 10px;
}

.page-about .track-card__year {
  font-family: var(--font-mono);
  font-size: 25px;
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: 0.02em;
  color: var(--ink);
}

.page-about .about-tag {
  display: inline-block;
  padding: 2px 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--ink);
  border: 1px solid var(--ink);
}

.page-about .about-tag--start {
  background: var(--cool);
}

.page-about .about-tag--grow {
  background: var(--amber);
}

.page-about .about-tag--deep {
  background: var(--neon);
}

.page-about .track-card__title {
  margin: 10px 0 6px;
  font-family: var(--font-body);
  font-size: 16px;
  font-weight: 600;
  color: var(--ink);
}

.page-about .track-card__text {
  margin: 0;
  max-width: 56ch;
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--about-body);
}

/* ---------- 资质 ---------- */

.page-about .about-cred {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
}

.page-about .cred-card {
  padding: 20px 18px;
  border: 2px solid var(--ink);
  background: var(--paper);
}

.page-about .cred-card__year {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  padding: 2px 8px;
  color: var(--neon);
  background: var(--ink);
}

.page-about .cred-card__title {
  margin: 12px 0 8px;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 600;
  line-height: 1.36;
  color: var(--ink);
}

.page-about .cred-card p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--about-body);
}

/* ---------- 合作生态 ---------- */

.page-about .about-eco {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
}

.page-about .eco-item {
  display: flex;
  gap: 14px;
  padding: 18px 0;
  border-top: 1px solid var(--about-line-ink);
  transition: background-color 0.18s ease;
}

.page-about .eco-item:first-child {
  border-top: 2px solid var(--ink);
}

.page-about .eco-item:hover,
.page-about .eco-item:focus-within,
.page-about .eco-item:focus {
  background: rgba(59, 240, 196, 0.09);
  outline: none;
}

.page-about .eco-item:focus-visible {
  outline: 2px solid var(--neon);
  outline-offset: 2px;
}

.page-about .eco-item__swatch {
  flex: none;
  width: 14px;
  height: 14px;
  margin-top: 4px;
  border: 2px solid var(--ink);
}

.page-about .eco-item__swatch--a {
  background: var(--neon);
}

.page-about .eco-item__swatch--b {
  background: var(--amber);
}

.page-about .eco-item__swatch--c {
  background: var(--cool);
}

.page-about .eco-item__body {
  min-width: 0;
}

.page-about .eco-item__title {
  margin: 0 0 6px;
  font-family: var(--font-body);
  font-size: 16px;
  font-weight: 600;
  color: var(--ink);
}

.page-about .eco-item__base {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--about-body);
}

.page-about .eco-item__more {
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  margin: 0;
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--mid);
  transition: max-height 0.26s ease, opacity 0.2s ease, margin-top 0.26s ease;
}

.page-about .eco-item:hover .eco-item__more,
.page-about .eco-item:focus-within .eco-item__more {
  max-height: 140px;
  opacity: 1;
  margin-top: 8px;
}

/* ---------- 区域 ---------- */

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

.page-about .about-region__text p {
  margin: 0 0 14px;
  max-width: 58ch;
  font-size: 16px;
  line-height: 1.74;
  color: var(--about-body);
}

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

.page-about .about-legend {
  list-style: none;
  margin: 0;
  padding: 18px 16px;
  border: 2px solid var(--ink);
  background: var(--night);
}

.page-about .legend-item {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  padding: 7px 0;
  font-size: 13px;
  line-height: 1.6;
  color: var(--cool);
}

.page-about .legend-item__swatch {
  flex: none;
  width: 12px;
  height: 12px;
  margin-top: 4px;
  border: 2px solid var(--cool);
}

.page-about .legend-item__swatch--core {
  background: var(--neon);
  border-color: var(--neon);
}

.page-about .legend-item__swatch--wide {
  background: var(--teal);
  border-color: var(--teal);
}

.page-about .legend-item__swatch--all {
  background: transparent;
}

/* ---------- 行动区 ---------- */

.page-about .about-cta {
  margin-top: 28px;
  padding-top: 22px;
  border-top: 2px solid var(--ink);
}

.page-about .about-cta p {
  margin: 0 0 16px;
  max-width: 58ch;
  font-size: 15px;
  line-height: 1.72;
  color: var(--about-body);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .about-cta .btn {
  border-color: var(--ink);
  color: var(--ink);
}

.page-about .about-cta .btn--primary {
  border-color: var(--ink);
  background: var(--neon);
  color: var(--ink);
}

.page-about .about-cta .btn--primary:hover {
  background: var(--teal);
  color: var(--paper);
}

.page-about .about-cta .btn--ghost:hover {
  background: var(--ink);
  color: var(--paper);
}

/* ---------- 触摸设备：展开内容常显 ---------- */

@media (hover: none) {
  .page-about .flow-step__more,
  .page-about .eco-item__more {
    max-height: 200px;
    opacity: 1;
    margin-top: 8px;
  }
}

/* ---------- 平板 ---------- */

@media (min-width: 640px) {
  .page-about .about-flow {
    padding: 34px 30px 48px;
  }

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

  .page-about .about-cred {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-region {
    grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .about-ink {
    margin-left: -30px;
    margin-right: -30px;
    padding: 34px 30px 38px;
  }
}

/* ---------- 桌面：左右分屏 ---------- */

@media (min-width: 1000px) {
  .page-about .about-shell {
    grid-template-columns: minmax(0, 1fr) minmax(0, 2.15fr);
    gap: 54px;
    align-items: start;
    padding-top: 36px;
  }

  .page-about .about-rail__sticky {
    position: sticky;
    top: calc(var(--band-h) + var(--bar-h) + 26px);
  }

  .page-about .about-rail__years {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .about-rail__years > li {
    flex: initial;
  }

  .page-about .about-year {
    min-width: 0;
    flex-direction: row;
    align-items: baseline;
    gap: 12px;
    padding: 11px 0 11px 14px;
    border: 0;
    border-left: 2px solid var(--about-line-night);
  }

  .page-about .about-year:hover,
  .page-about .about-year:focus-visible {
    background: transparent;
    border-left-color: var(--neon);
    transform: translateX(4px);
  }

  .page-about .about-year__note {
    font-size: 11.5px;
  }

  .page-about .about-flow {
    padding: 44px 44px 60px;
  }

  .page-about .about-hero__title {
    max-width: 15ch;
  }

  .page-about .about-sec {
    margin-top: 62px;
  }

  .page-about .about-ink {
    margin-left: -44px;
    margin-right: -44px;
    padding: 40px 44px 46px;
  }

  .page-about .about-stat__value {
    font-size: 34px;
  }
}

@media (min-width: 1180px) {
  .page-about .about-figure--hero img {
    aspect-ratio: 16 / 8;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .flow-step,
  .page-about .about-year,
  .page-about .flow-step__more,
  .page-about .eco-item__more {
    transition: none;
  }

  .page-about .flow-step:hover,
  .page-about .flow-step:focus-within {
    transform: none;
  }

  .page-about .about-year:hover,
  .page-about .about-year:focus-visible {
    transform: none;
  }
}
<<<END>>>