.page-about .about-crumb {
  padding-top: var(--space-6);
}

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

/* ---------- 首屏 ---------- */
.page-about .about-open {
  padding-top: var(--space-2);
}

.page-about .about-open__grid {
  display: grid;
  gap: var(--space-4);
  align-items: end;
}

.page-about .about-open__title {
  font-family: var(--font-heading);
  font-size: var(--text-4xl);
  font-weight: 800;
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
  margin: var(--space-2) 0 var(--space-3);
  max-width: 20ch;
}

.page-about .about-open__lead {
  font-size: var(--text-lg);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
  max-width: 46ch;
  margin: 0 0 var(--space-3);
}

.page-about .about-open__facts {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
}

.page-about .about-open__media {
  margin: 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  position: relative;
}

@media (min-width: 880px) {
  .page-about .about-open__grid {
    grid-template-columns: minmax(0, 1.2fr) minmax(0, 0.8fr);
    gap: var(--space-6);
  }
}

/* ---------- 阶段带 + 叙述流 ---------- */
.page-about .about-story {
  padding-top: var(--space-8);
}

.page-about .about-flow {
  display: grid;
  gap: var(--space-4);
}

.page-about .about-stages__label {
  margin: 0 0 var(--space-2);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--color-ink-muted);
}

.page-about .about-stages__list {
  list-style: none;
  margin: 0;
  padding: 0 0 var(--space-1);
  display: flex;
  gap: var(--space-1);
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-stage {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: 8px var(--space-2);
  border-radius: var(--radius-pill);
  background: var(--color-surface-alt);
  border: var(--border-thin) solid transparent;
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-ink-soft);
  text-decoration: none;
  white-space: nowrap;
  transition: color 180ms ease, border-color 180ms ease, background-color 180ms ease;
}

.page-about .about-stage__dot {
  width: 8px;
  height: 8px;
  flex: 0 0 auto;
  border-radius: 50%;
  background: var(--color-primary);
  opacity: 0.5;
  display: none;
  transition: opacity 180ms ease, transform 180ms ease;
}

.page-about .about-stage:hover,
.page-about .about-stage:focus-visible {
  color: var(--color-primary);
  border-color: var(--color-primary);
}

.page-about .about-stage:hover .about-stage__dot,
.page-about .about-stage:focus-visible .about-stage__dot {
  opacity: 1;
  transform: scale(1.3);
}

.page-about .about-flow__body {
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
  min-width: 0;
}

@media (min-width: 980px) {
  .page-about .about-flow {
    grid-template-columns: 190px minmax(0, 1fr);
    column-gap: var(--space-6);
    row-gap: var(--space-4);
  }

  .page-about .about-stages {
    grid-column: 1;
    grid-row: 1;
    align-self: start;
    position: sticky;
    top: 104px;
  }

  .page-about .about-flow__body {
    grid-column: 2;
    grid-row: 1;
  }

  .page-about .about-stages__list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding-bottom: 0;
    border-left: var(--border-thin) solid var(--color-line);
  }

  .page-about .about-stage {
    position: relative;
    border-radius: 0;
    background: transparent;
    border-color: transparent;
    padding: 10px 0 10px var(--space-3);
    white-space: normal;
    line-height: 1.5;
  }

  .page-about .about-stage::before {
    content: "";
    position: absolute;
    left: -1px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: transparent;
    transition: background-color 180ms ease;
  }

  .page-about .about-stage:hover::before,
  .page-about .about-stage:focus-visible::before {
    background: var(--color-primary);
  }

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

/* ---------- 叙述块 ---------- */
.page-about .about-panel {
  position: relative;
  padding-left: var(--space-3);
  scroll-margin-top: 112px;
}

.page-about .about-panel::before {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  bottom: 6px;
  width: 2px;
  background: color-mix(in srgb, var(--color-primary) 40%, var(--color-surface));
  transition: width 180ms ease, background-color 180ms ease;
}

.page-about .about-panel:hover::before {
  width: 4px;
  background: var(--color-primary);
}

.page-about .about-panel__step {
  margin: 0 0 var(--space-1);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--color-primary);
}

.page-about .about-panel__title {
  margin: 0 0 var(--space-3);
  font-family: var(--font-heading);
  font-size: var(--text-xl);
  font-weight: 700;
  line-height: var(--leading-heading);
  color: var(--color-ink);
  max-width: 32ch;
}

.page-about .about-panel__body {
  max-width: 68ch;
}

.page-about .about-panel__body p {
  margin: 0 0 var(--space-2);
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

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

.page-about .about-panel--narrow .about-panel__body {
  max-width: 58ch;
}

.page-about .about-panel__media {
  margin: var(--space-3) 0 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  position: relative;
  max-width: 620px;
}

.page-about .about-panel--wide .about-panel__media {
  max-width: 100%;
}

/* ---------- 引语 ---------- */
.page-about .about-quote {
  margin: var(--space-3) 0 0;
  padding: var(--space-3) var(--space-4);
  background: var(--color-primary-soft);
  border: var(--border-thin) solid var(--color-primary);
  border-radius: var(--radius-sm);
  font-size: var(--text-lg);
  font-weight: 700;
  line-height: 1.6;
  color: var(--color-ink);
  max-width: 56ch;
}

/* ---------- 数字带 ---------- */
.page-about .about-band {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-radius: var(--radius-lg);
  padding: var(--space-4) var(--space-3);
}

.page-about .about-band__label {
  margin: 0 0 var(--space-3);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.16em;
  color: var(--color-contrast-accent);
}

.page-about .about-band__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-3) var(--space-3);
}

.page-about .about-band__stat {
  padding-top: var(--space-2);
  border-top: var(--border-thin) solid var(--color-contrast-line);
  transition: border-color 180ms ease;
}

.page-about .about-band__stat:hover {
  border-top-color: var(--color-contrast-accent);
}

.page-about .about-band__num {
  display: flex;
  align-items: baseline;
  gap: 4px;
  margin: 0 0 4px;
  font-family: var(--font-mono);
  font-size: var(--text-3xl);
  font-weight: 600;
  line-height: 1.1;
  color: var(--color-contrast-ink);
}

.page-about .about-band__num .unit {
  font-family: var(--font-body);
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--color-contrast-accent);
}

.page-about .about-band__name {
  margin: 0 0 6px;
  font-size: var(--text-sm);
  font-weight: 700;
  color: var(--color-contrast-ink);
}

.page-about .about-band__note {
  margin: 0;
  font-size: var(--text-xs);
  line-height: 1.7;
  color: color-mix(in srgb, var(--color-contrast-ink) 68%, var(--color-contrast-surface));
  transition: color 180ms ease;
}

.page-about .about-band__stat:hover .about-band__note {
  color: var(--color-contrast-ink);
}

@media (min-width: 640px) {
  .page-about .about-band__grid {
    grid-template-columns: repeat(6, 1fr);
  }

  .page-about .about-band__stat--wide {
    grid-column: span 3;
  }

  .page-about .about-band__stat--mid {
    grid-column: span 2;
  }
}

/* ---------- 三条规矩 ---------- */
.page-about .about-rules {
  list-style: none;
  counter-reset: rule;
  margin: var(--space-3) 0 0;
  padding: 0;
  display: grid;
  gap: var(--space-2);
}

.page-about .about-rule {
  counter-increment: rule;
  position: relative;
  padding: var(--space-3) var(--space-3) var(--space-3) calc(var(--space-6) + var(--space-1));
  background: var(--color-surface-alt);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  transition: border-color 180ms ease, transform 180ms ease;
}

.page-about .about-rule:hover {
  border-color: var(--color-primary);
  transform: translateY(-2px);
}

.page-about .about-rule::before {
  content: counter(rule, decimal-leading-zero);
  position: absolute;
  left: var(--space-3);
  top: var(--space-3);
  font-family: var(--font-mono);
  font-size: var(--text-lg);
  font-weight: 600;
  color: var(--color-primary);
}

.page-about .about-rule__head {
  margin: 0 0 6px;
  font-size: var(--text-base);
  font-weight: 700;
  color: var(--color-ink);
}

.page-about .about-rule__text {
  margin: 0;
  font-size: var(--text-sm);
  line-height: 1.75;
  color: var(--color-ink-soft);
}

/* ---------- 延伸阅读 ---------- */
.page-about .about-next {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-2);
  margin-top: var(--space-2);
}

.page-about .about-next__card {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: var(--space-3);
  background: var(--color-surface-alt);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  text-decoration: none;
  transition: border-color 180ms ease, background-color 180ms ease, transform 180ms ease;
}

.page-about .about-next__card:hover,
.page-about .about-next__card:focus-visible {
  border-color: var(--color-primary);
  background: var(--color-primary-soft);
  transform: translateY(-2px);
}

.page-about .about-next__kicker {
  margin: 0;
  font-size: var(--text-sm);
  font-weight: 700;
  color: var(--color-ink);
}

.page-about .about-next__desc {
  margin: 0;
  font-size: var(--text-sm);
  line-height: 1.7;
  color: var(--color-ink-soft);
}

.page-about .about-next__go {
  margin-top: auto;
  padding-top: var(--space-1);
  align-self: flex-start;
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--color-primary);
  border-bottom: var(--border-thin) solid var(--color-primary);
  transition: color 180ms ease, border-color 180ms ease;
}

.page-about .about-next__card:hover .about-next__go,
.page-about .about-next__card:focus-visible .about-next__go {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
}

@media (min-width: 640px) {
  .page-about .about-next {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1040px) {
  .page-about .about-next {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 行动出口 ---------- */
.page-about .about-cta {
  background: var(--color-primary-soft);
  border: var(--border-thin) solid var(--color-primary);
  border-radius: var(--radius-lg);
  padding: var(--space-4) var(--space-3);
}

.page-about .about-cta__title {
  margin: 0 0 var(--space-2);
  font-family: var(--font-heading);
  font-size: var(--text-xl);
  font-weight: 700;
  line-height: var(--leading-heading);
  color: var(--color-ink);
}

.page-about .about-cta__text {
  margin: 0 0 var(--space-3);
  max-width: 62ch;
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-about .about-cta__strong {
  font-weight: 700;
  color: var(--color-ink);
}

.page-about .about-cta__strong.num {
  font-family: var(--font-mono);
  font-size: var(--text-lg);
  letter-spacing: 0.02em;
}

.page-about .about-cta__btn {
  display: inline-flex;
  align-items: center;
}
<<<END>>>