.page-about {
  --about-rail-pad: var(--space-3);
  --about-chapter-gap: var(--space-6);
  background: var(--color-surface);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: var(--leading-body);
}

.page-about .about-top {
  padding-top: var(--space-4);
}

.page-about .breadcrumb {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  letter-spacing: 0;
}

/* ---------- 页首说明 ---------- */
.page-about .about-head {
  padding: var(--space-6) 0 var(--space-8);
}

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

.page-about .about-head__title {
  margin: 0;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-2xl);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  transform: skewX(-2deg);
  transform-origin: left center;
  max-width: 22ch;
}

.page-about .about-head__text {
  display: grid;
  gap: var(--space-3);
  max-width: var(--measure);
}

.page-about .about-head__text p {
  margin: 0;
  color: var(--color-ink-soft);
}

.page-about .about-head__text p:first-child {
  color: var(--color-ink);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-chapter {
  padding: var(--space-8) 0;
  background: var(--color-surface);
}

.page-about .about-chapter--alt {
  background: var(--color-surface-alt);
}

.page-about .about-chapter--contrast {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.page-about .about-chapter__grid {
  display: grid;
  gap: var(--about-chapter-gap);
}

.page-about .about-chapter__rail {
  padding: var(--about-rail-pad);
  background: var(--color-primary-soft);
  border-left: 8px solid var(--color-primary);
  border-radius: var(--radius-md);
}

.page-about .about-chapter__rail--accent {
  background: var(--color-highlight);
  border-left-color: var(--color-accent);
}

.page-about .about-chapter__rail--primary {
  background: var(--color-primary-soft);
  border-left-color: var(--color-primary);
}

.page-about .about-chapter__rail--contrast {
  background: color-mix(in srgb, var(--color-contrast-ink) 10%, var(--color-contrast-surface));
  border-left-color: var(--color-contrast-accent);
}

.page-about .about-chapter__title {
  margin: var(--space-2) 0 0;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-lg);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
}

.page-about .about-chapter--contrast .about-chapter__title {
  color: var(--color-contrast-ink);
}

.page-about .about-chapter__body {
  min-width: 0;
}

.page-about .about-chapter__body p {
  margin: 0 0 var(--space-3);
  max-width: var(--measure);
}

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

.page-about .about-chapter--contrast .about-chapter__body p {
  color: var(--color-contrast-ink);
}

.page-about .about-subhead {
  margin: var(--space-6) 0 var(--space-2);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-base);
  line-height: var(--leading-heading);
  padding-top: var(--space-2);
  border-top: var(--border-thick) solid var(--color-primary);
}

.page-about .about-chapter__rail--accent + .about-chapter__body .about-subhead {
  border-top-color: var(--color-accent);
}

/* ---------- 折叠说明 ---------- */
.page-about .about-note {
  margin-top: var(--space-3);
  font-size: var(--text-sm);
  line-height: var(--leading-body);
}

.page-about .about-note summary {
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-primary);
  padding: var(--space-1) 0;
  list-style: none;
  border-top: var(--border-thin) solid color-mix(in srgb, var(--color-primary) 34%, var(--color-surface));
  border-bottom: var(--border-thin) solid color-mix(in srgb, var(--color-primary) 34%, var(--color-surface));
}

.page-about .about-chapter__rail--accent .about-note summary {
  color: var(--color-accent);
  border-top-color: color-mix(in srgb, var(--color-accent) 34%, var(--color-surface));
  border-bottom-color: color-mix(in srgb, var(--color-accent) 34%, var(--color-surface));
}

.page-about .about-note summary::-webkit-details-marker {
  display: none;
}

.page-about .about-note summary::after {
  content: " ＋";
}

.page-about .about-note[open] summary::after {
  content: " －";
}

.page-about .about-note summary:focus-visible {
  outline: var(--border-thick) solid var(--color-focus);
  outline-offset: 2px;
}

.page-about .about-note p {
  margin: var(--space-2) 0 0;
  color: var(--color-ink-soft);
}

.page-about .about-note--contrast summary {
  color: var(--color-contrast-accent);
  border-top-color: var(--color-contrast-line);
  border-bottom-color: var(--color-contrast-line);
}

.page-about .about-note--contrast p {
  color: var(--color-contrast-ink);
}

/* ---------- 边界清单 ---------- */
.page-about .about-boundary {
  display: grid;
  gap: var(--space-3);
  margin-top: var(--space-4);
}

.page-about .about-boundary__col {
  padding: var(--space-3);
  background: var(--color-surface);
  border-radius: var(--radius-md);
}

.page-about .about-boundary__col--yes {
  border-top: 8px solid var(--color-accent);
}

.page-about .about-boundary__col--no {
  border-top: 8px solid var(--color-ink-muted);
}

.page-about .about-boundary__list {
  list-style: none;
  margin: var(--space-2) 0 0;
  padding: 0;
  display: grid;
  gap: var(--space-2);
}

.page-about .about-boundary__list li {
  position: relative;
  padding-left: var(--space-3);
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

.page-about .about-boundary__col--yes .about-boundary__list li {
  color: var(--color-ink);
}

.page-about .about-boundary__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 8px;
  height: 8px;
  background: var(--color-accent);
}

.page-about .about-boundary__col--no .about-boundary__list li::before {
  background: var(--color-ink-muted);
}

/* ---------- 横向数据带 ---------- */
.page-about .about-band {
  padding: var(--space-6) 0;
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.page-about .about-band--primary {
  background: var(--color-primary);
  color: var(--color-primary-ink);
}

.page-about .about-band--accent {
  background: var(--color-accent);
  color: var(--color-accent-ink);
}

.page-about .about-band__list {
  list-style: none;
  margin: 0;
  padding: 0 0 var(--space-2);
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: minmax(200px, 82%);
  gap: var(--space-4);
  overflow-x: auto;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-band__item {
  scroll-snap-align: start;
  display: grid;
  gap: var(--space-1);
  align-content: start;
}

.page-about .about-band__num {
  font-family: var(--font-mono);
  font-size: var(--text-xl);
  line-height: 1;
  letter-spacing: -0.02em;
  white-space: nowrap;
}

.page-about .about-band--contrast .about-band__num {
  color: var(--color-contrast-accent);
}

.page-about .about-band__label {
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: inherit;
  opacity: 0.84;
  max-width: 30ch;
}

/* ---------- 阶段刻度 ---------- */
.page-about .about-steps {
  list-style: none;
  margin: var(--space-3) 0 0;
  padding: 0;
  display: grid;
  gap: 0;
  border-top: var(--border-thin) solid color-mix(in srgb, var(--color-accent) 30%, var(--color-highlight));
}

.page-about .about-steps__link {
  display: grid;
  grid-template-columns: 12px 1fr;
  align-items: center;
  gap: var(--space-2);
  min-height: 44px;
  padding: var(--space-1) 0;
  text-decoration: none;
  color: var(--color-ink);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-sm);
}

.page-about .about-steps__mark {
  width: 12px;
  height: 12px;
  background: var(--color-accent);
  border-radius: var(--radius-sm);
}

.page-about .about-steps__link:hover .about-steps__text {
  text-decoration: underline;
  text-underline-offset: 4px;
}

.page-about .about-steps__link:focus-visible {
  outline: var(--border-thick) solid var(--color-focus);
  outline-offset: 2px;
}

.page-about .about-stage {
  padding: var(--space-3) 0;
  border-top: var(--border-thick) solid var(--color-accent);
}

.page-about .about-stage:first-child {
  border-top-width: 8px;
}

.page-about .about-stage__head {
  margin: 0 0 var(--space-2);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-base);
  line-height: var(--leading-heading);
}

.page-about .about-stage p {
  margin: 0;
  color: var(--color-ink-soft);
  max-width: var(--measure);
}

/* ---------- 图片容器 ---------- */
.page-about .about-figure {
  margin: 0;
  padding: var(--space-6) 0;
  background: var(--color-surface-alt);
}

.page-about .about-figure--wide {
  background: var(--color-surface-deep);
}

.page-about .about-figure .media-frame {
  margin: 0;
}

.page-about .about-figure figcaption {
  margin-top: var(--space-2);
}

/* ---------- 维度定义表 ---------- */
.page-about .about-dim {
  margin: var(--space-4) 0 0;
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .about-dim__row {
  display: grid;
  gap: var(--space-1);
  padding: var(--space-3) 0;
  border-bottom: var(--border-thin) solid var(--color-line);
}

.page-about .about-dim__row dt {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: var(--weight-body);
  color: var(--color-primary);
  letter-spacing: 0.02em;
}

.page-about .about-dim__row dd {
  margin: 0;
  color: var(--color-ink-soft);
  max-width: var(--measure);
}

/* ---------- 五维列表 ---------- */
.page-about .about-dims {
  list-style: none;
  margin: var(--space-3) 0 0;
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .about-dims__item {
  display: grid;
  grid-template-columns: 32px 1fr;
  grid-template-areas:
    "num name"
    "num desc";
  gap: 0 var(--space-2);
  padding: var(--space-2) 0;
  border-bottom: var(--border-thin) solid var(--color-line);
}

.page-about .about-dims__num {
  grid-area: num;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--color-accent);
  line-height: var(--leading-body);
}

.page-about .about-dims__name {
  grid-area: name;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-base);
  line-height: var(--leading-heading);
}

.page-about .about-dims__desc {
  grid-area: desc;
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

/* ---------- 团队分工 ---------- */
.page-about .about-team {
  list-style: none;
  margin: var(--space-3) 0 var(--space-4);
  padding: 0;
  display: grid;
  gap: var(--space-2);
}

.page-about .about-team__item {
  padding: var(--space-3);
  background: var(--color-surface);
  border-top: 8px solid var(--color-primary);
  border-radius: var(--radius-md);
  display: grid;
  gap: var(--space-1);
}

.page-about .about-team__role {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-base);
}

.page-about .about-team__count {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--color-primary);
}

.page-about .about-team__desc {
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}

/* ---------- 三级复核 ---------- */
.page-about .about-review {
  list-style: none;
  margin: var(--space-3) 0;
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .about-review__item {
  display: grid;
  grid-template-columns: 44px 1fr;
  gap: var(--space-2);
  align-items: start;
  padding: var(--space-3) 0;
  border-bottom: var(--border-thin) solid var(--color-line);
}

.page-about .about-review__num {
  font-family: var(--font-mono);
  font-size: var(--text-lg);
  line-height: 1;
  color: var(--color-accent);
}

.page-about .about-review__body {
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
  max-width: var(--measure);
}

/* ---------- 运营原则 ---------- */
.page-about .about-principles {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .about-principles__item {
  display: grid;
  grid-template-columns: 40px 1fr;
  gap: var(--space-1) var(--space-2);
  padding: var(--space-4) 0;
  border-top: var(--border-thick) solid var(--color-primary);
}

.page-about .about-principles__item:first-child {
  border-top-width: 8px;
}

.page-about .about-principles__num {
  grid-row: 1 / span 2;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--color-primary);
  line-height: var(--leading-heading);
}

.page-about .about-principles__title {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-base);
  line-height: var(--leading-heading);
}

.page-about .about-principles__item p {
  grid-column: 2;
  margin: 0;
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
  max-width: var(--measure);
}

/* ---------- 合规信息 ---------- */
.page-about .about-records {
  margin: 0 0 var(--space-4);
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .about-records__row {
  display: grid;
  gap: var(--space-1);
  padding: var(--space-2) 0;
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
}

.page-about .about-records__row dt {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
  color: var(--color-contrast-accent);
}

.page-about .about-records__row dd {
  margin: 0;
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: var(--color-contrast-ink);
  overflow-wrap: anywhere;
}

.page-about .about-links {
  list-style: none;
  margin: var(--space-4) 0 0;
  padding: 0;
  display: grid;
  gap: 0;
  border-top: var(--border-thin) solid var(--color-contrast-line);
}

.page-about .about-links li {
  display: grid;
  gap: 0;
  padding: var(--space-2) 0;
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
}

.page-about .about-links a {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-base);
  color: var(--color-contrast-accent);
  text-decoration: none;
  justify-self: start;
}

.page-about .about-links a:hover {
  text-decoration: underline;
  text-underline-offset: 4px;
}

.page-about .about-links a:focus-visible {
  outline: var(--border-thick) solid var(--color-contrast-accent);
  outline-offset: 2px;
}

.page-about .about-links__note {
  font-size: var(--text-sm);
  line-height: var(--leading-body);
  color: color-mix(in srgb, var(--color-contrast-ink) 72%, var(--color-contrast-surface));
}

/* ---------- 焦点与动效 ---------- */
.page-about a:focus-visible,
.page-about summary:focus-visible {
  outline: var(--border-thick) solid var(--color-focus);
  outline-offset: 2px;
}

@media (prefers-reduced-motion: reduce) {
  .page-about [data-reveal] {
    transition: none;
    transform: none;
    opacity: 1;
  }
}

/* ---------- 平板及以上 ---------- */
@media (min-width: 720px) {
  .page-about .about-head {
    padding: var(--space-8) 0 var(--space-8);
  }

  .page-about .about-head__inner {
    gap: var(--space-6);
  }

  .page-about .about-boundary {
    grid-template-columns: 1fr 1fr;
  }

  .page-about .about-band {
    padding: var(--space-6) 0;
  }

  .page-about .about-band__list {
    grid-auto-flow: row;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    grid-auto-columns: auto;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .about-dim__row {
    grid-template-columns: 132px minmax(0, 1fr);
    gap: var(--space-3);
    align-items: baseline;
  }

  .page-about .about-dims__item {
    grid-template-columns: 40px minmax(0, 1fr) minmax(0, 1.4fr);
    grid-template-areas: "num name desc";
    align-items: baseline;
    gap: var(--space-3);
  }

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

  .page-about .about-records__row {
    grid-template-columns: 128px minmax(0, 1fr);
    gap: var(--space-3);
    align-items: baseline;
  }

  .page-about .about-links li {
    grid-template-columns: 180px minmax(0, 1fr);
    gap: var(--space-3);
    align-items: baseline;
  }
}

/* ---------- 桌面七列错位 ---------- */
@media (min-width: 960px) {
  .page-about .about-chapter {
    padding: var(--section-y) 0;
  }

  .page-about .about-chapter__grid {
    display: grid;
    grid-template-columns: repeat(7, minmax(0, 1fr));
    gap: var(--gutter);
    align-items: start;
  }

  .page-about .about-chapter__rail {
    padding: var(--space-4) var(--space-3);
  }

  .page-about .about-chapter__title {
    font-size: var(--text-xl);
  }

  .page-about .about-chapter--a .about-chapter__rail {
    grid-column: 1 / span 3;
  }

  .page-about .about-chapter--a .about-chapter__body {
    grid-column: 4 / span 4;
  }

  .page-about .about-chapter--b .about-chapter__rail {
    grid-column: 1 / span 2;
  }

  .page-about .about-chapter--b .about-chapter__body {
    grid-column: 3 / span 5;
  }

  .page-about .about-chapter--c .about-chapter__rail {
    grid-column: 1 / span 2;
  }

  .page-about .about-chapter--c .about-chapter__body {
    grid-column: 4 / span 4;
  }

  .page-about .about-chapter--d .about-chapter__rail {
    grid-column: 5 / span 3;
    grid-row: 1;
  }

  .page-about .about-chapter--d .about-chapter__body {
    grid-column: 1 / span 4;
    grid-row: 1;
  }

  .page-about .about-chapter--e .about-chapter__rail {
    grid-column: 1 / span 7;
    display: flex;
    align-items: baseline;
    gap: var(--space-4);
    border-left-width: 16px;
  }

  .page-about .about-chapter--e .about-chapter__title {
    margin-top: 0;
  }

  .page-about .about-chapter--e .about-chapter__body {
    grid-column: 2 / span 5;
  }

  .page-about .about-figure {
    padding: var(--section-y) 0;
  }
}
</final>
</PAGE_CSS>