.page-about {
  --ab-rail: 172px;
  --ab-rule: 1px solid var(--rock);
  --ab-gap: clamp(32px, 5vw, 72px);
  padding-bottom: clamp(48px, 8vw, 96px);
}

.page-about .breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-block: 20px 0;
  font-size: var(--fs-13);
  color: var(--note);
}

.page-about .breadcrumb a {
  color: var(--snow);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--ease);
}

.page-about .breadcrumb a:hover,
.page-about .breadcrumb a:focus-visible {
  border-bottom-color: var(--turf);
}

.page-about .breadcrumb__sep {
  color: var(--rock);
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
  padding-block: 28px 0;
}

.page-about .about-hero__text .eyebrow {
  font-size: var(--fs-12);
  letter-spacing: 0.2em;
  color: var(--clay);
  margin: 0 0 14px;
}

.page-about .about-hero h1 {
  margin: 0;
  font-size: clamp(32px, 5.4vw, 64px);
  line-height: 1.06;
  letter-spacing: -0.035em;
  color: var(--snow);
  max-width: 15em;
}

.page-about .about-hero__lede {
  margin: 20px 0 0;
  max-width: 34em;
  font-size: var(--fs-17);
  line-height: 1.85;
  color: var(--note);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.page-about .about-hero__media {
  margin: 0;
}

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

/* ---------- 数字带 ---------- */

.page-about .about-figures {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: clamp(28px, 4vw, 48px);
  background: var(--rock);
  border: var(--ab-rule);
}

.page-about .about-figure {
  background: var(--ink);
  padding: 16px 14px 18px;
}

.page-about .about-figure__num {
  display: block;
  font-family: var(--mono);
  font-size: clamp(24px, 4vw, 32px);
  line-height: 1;
  letter-spacing: -0.02em;
  font-variant-numeric: tabular-nums;
  color: var(--cyan);
}

.page-about .about-figure__label {
  display: block;
  margin-top: 8px;
  font-size: var(--fs-12);
  line-height: 1.5;
  color: var(--note);
}

/* ---------- 主体双栏 ---------- */

.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 32px;
  padding-block: clamp(40px, 6vw, 72px) 0;
}

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

.page-about .about-index__title {
  margin: 0 0 12px;
  font-size: var(--fs-12);
  letter-spacing: 0.18em;
  color: var(--clay);
}

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

.page-about .about-index__list li {
  flex: 0 0 auto;
}

.page-about .about-index__link {
  display: block;
  min-width: 136px;
  padding: 10px 14px;
  border: var(--ab-rule);
  background: var(--stand);
  text-decoration: none;
  transition: border-color var(--ease), background-color var(--ease);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  border-color: var(--turf);
  background: var(--ink);
}

.page-about .about-index__year {
  display: block;
  font-family: var(--mono);
  font-size: var(--fs-15);
  line-height: 1.2;
  font-variant-numeric: tabular-nums;
  color: var(--cyan);
}

.page-about .about-index__note {
  display: block;
  margin-top: 5px;
  font-size: var(--fs-12);
  line-height: 1.5;
  color: var(--note);
}

/* ---------- 章节 ---------- */

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

.page-about .about-chapter {
  border-top: var(--ab-rule);
  padding-block: clamp(24px, 4vw, 36px) clamp(32px, 5vw, 52px);
  scroll-margin-top: 96px;
}

.page-about .about-stream > .about-chapter:first-child {
  border-top: 0;
  padding-top: 0;
}

.page-about .chapter-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 16px;
  margin-bottom: 18px;
}

.page-about .chapter-year {
  margin: 0;
  font-family: var(--mono);
  font-size: clamp(36px, 7vw, 64px);
  line-height: 0.92;
  letter-spacing: -0.04em;
  font-variant-numeric: tabular-nums;
  color: var(--cyan);
}

.page-about .chapter-title {
  margin: 0;
  max-width: 22em;
  font-size: clamp(20px, 3.2vw, 30px);
  line-height: 1.3;
  letter-spacing: -0.015em;
  color: var(--snow);
}

.page-about .about-chapter p {
  margin: 0 0 1.05em;
  max-width: 36em;
  font-size: var(--fs-15);
  line-height: 1.85;
  color: var(--note);
}

.page-about .about-chapter p.is-lead {
  font-size: var(--fs-17);
  color: var(--snow);
}

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

/* ---------- 版本三列 ---------- */

.page-about .version-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin-top: 24px;
}

.page-about .version-card {
  padding: 16px 16px 20px;
  border: var(--ab-rule);
  background: var(--stand);
  transition: border-color var(--ease);
  scroll-margin-top: 96px;
}

.page-about .version-card:hover {
  border-color: var(--turf);
}

.page-about .version-card__head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--rock);
  transition: transform var(--ease), border-color var(--ease);
}

.page-about .version-card:hover .version-card__head {
  transform: translateY(-2px);
  border-bottom-color: var(--turf);
}

.page-about .version-card__tag {
  font-family: var(--mono);
  font-size: var(--fs-15);
  letter-spacing: 0.06em;
  color: var(--clay);
}

.page-about .version-card__year {
  font-family: var(--mono);
  font-size: var(--fs-12);
  font-variant-numeric: tabular-nums;
  color: var(--note);
}

.page-about .version-card__title {
  margin: 14px 0 0;
  font-size: var(--fs-17);
  line-height: 1.45;
  color: var(--snow);
}

.page-about .version-card ul {
  margin: 12px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .version-card li {
  position: relative;
  padding-left: 15px;
  margin-bottom: 9px;
  font-size: var(--fs-13);
  line-height: 1.7;
  color: var(--note);
}

.page-about .version-card li:last-child {
  margin-bottom: 0;
}

.page-about .version-card li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.68em;
  width: 5px;
  height: 5px;
  background: var(--turf);
}

.page-about .about-versions-media {
  margin: 24px 0 0;
}

.page-about .about-versions-media img,
.page-about .team-media img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
}

.page-about .about-versions-media + p {
  margin-top: 22px;
}

/* ---------- 团队 ---------- */

.page-about .team-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 24px;
}

.page-about .team-media {
  margin: 0;
}

.page-about .team-roles {
  margin: 20px 0 0;
}

.page-about .team-role {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 6px;
  padding-block: 14px;
  border-top: var(--ab-rule);
}

.page-about .team-role dt {
  font-family: var(--mono);
  font-size: var(--fs-13);
  letter-spacing: 0.02em;
  color: var(--clay);
}

.page-about .team-role dd {
  margin: 0;
  font-size: var(--fs-13);
  line-height: 1.8;
  color: var(--note);
}

/* ---------- 合作 ---------- */

.page-about .partner-list {
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .partner-item {
  display: grid;
  grid-template-columns: 56px minmax(0, 1fr);
  gap: 14px;
  padding-block: 16px;
  border-top: var(--ab-rule);
}

.page-about .partner-item__num {
  font-family: var(--mono);
  font-size: clamp(24px, 4vw, 30px);
  line-height: 1;
  font-variant-numeric: tabular-nums;
  color: var(--turf);
}

.page-about .partner-item__body h3 {
  margin: 0 0 8px;
  font-size: var(--fs-17);
  line-height: 1.4;
  color: var(--snow);
}

.page-about .partner-item__body p {
  margin: 0;
  max-width: 34em;
  font-size: var(--fs-13);
  line-height: 1.8;
  color: var(--note);
}

/* ---------- 下一页入口 ---------- */

.page-about .about-next .chapter-title {
  margin-bottom: 20px;
}

.page-about .next-links {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 10px;
}

.page-about .next-link {
  display: block;
  padding: 16px 18px;
  border: var(--ab-rule);
  background: var(--stand);
  text-decoration: none;
  transition: border-color var(--ease), background-color var(--ease);
}

.page-about .next-link:hover,
.page-about .next-link:focus-visible {
  border-color: var(--turf);
  background: var(--ink);
}

.page-about .next-link__label {
  display: block;
  font-size: var(--fs-17);
  font-weight: 700;
  color: var(--snow);
}

.page-about .next-link__desc {
  display: block;
  margin-top: 6px;
  font-size: var(--fs-13);
  line-height: 1.7;
  color: var(--note);
}

/* ---------- 断点 ---------- */

@media (min-width: 640px) {
  .page-about .about-figures {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .team-role {
    grid-template-columns: 150px minmax(0, 1fr);
    gap: 20px;
  }

  .page-about .partner-item {
    grid-template-columns: 72px minmax(0, 1fr);
    gap: 20px;
  }

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

@media (min-width: 720px) {
  .page-about .version-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
    gap: clamp(28px, 4vw, 64px);
    align-items: end;
    padding-block: 40px 0;
  }

  .page-about .team-grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    gap: clamp(24px, 4vw, 48px);
    align-items: start;
  }
}

@media (min-width: 960px) {
  .page-about .about-body {
    grid-template-columns: var(--ab-rail) minmax(0, 1fr);
    gap: var(--ab-gap);
    align-items: start;
  }

  .page-about .about-index {
    position: sticky;
    top: 96px;
  }

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

  .page-about .about-index__list li {
    flex: initial;
  }

  .page-about .about-index__link {
    min-width: 0;
    padding: 9px 0 9px 14px;
    border-width: 0 0 0 1px;
    border-color: var(--rock);
    background: transparent;
  }

  .page-about .about-index__link:hover,
  .page-about .about-index__link:focus-visible {
    border-left-color: var(--turf);
    background: transparent;
  }

  .page-about .about-index__note {
    font-size: var(--fs-12);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index__link,
  .page-about .version-card,
  .page-about .version-card__head,
  .page-about .next-link,
  .page-about .breadcrumb a {
    transition: none;
  }

  .page-about .version-card:hover .version-card__head {
    transform: none;
  }
}
<<<END>>>