.page-about {
  --about-rail: 88px;
  --about-measure: 720px;
  --about-space: clamp(56px, 8vw, 112px);
  background-color: var(--ink);
  color: var(--paper);
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  line-height: 1.75;
  padding-bottom: clamp(72px, 10vw, 140px);
  overflow-x: hidden;
}

.page-about .breadcrumb {
  margin: clamp(16px, 3vw, 32px) 0 clamp(24px, 4vw, 48px);
  font-size: var(--fs-note);
  letter-spacing: 0.08em;
  color: var(--fog);
}

.page-about .breadcrumb a {
  color: var(--fog);
  text-decoration: none;
}

.page-about .breadcrumb a:hover {
  color: var(--paper);
}

.page-about .breadcrumb__sep {
  margin: 0 0.5em;
  color: var(--rule);
}

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

.page-about .about-rail {
  display: none;
}

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

/* 首屏 */
.page-about .about-hero {
  padding-bottom: var(--about-space);
}

.page-about .eyebrow {
  color: var(--fox);
  font-family: var(--font-mono);
  font-size: var(--fs-note);
  letter-spacing: 0.24em;
  text-transform: uppercase;
}

.page-about h1 {
  margin: 16px 0 0;
  font-size: clamp(2.25rem, 5.6vw, 3.75rem);
  line-height: 1.06;
  letter-spacing: -0.02em;
  font-weight: 900;
  max-width: 15em;
}

.page-about .about-lede {
  margin: 28px 0 0;
  max-width: 34em;
  font-size: clamp(1.0625rem, 1.6vw, 1.25rem);
  line-height: 1.8;
  color: var(--paper);
}

.page-about .about-facts {
  display: flex;
  flex-wrap: wrap;
  gap: 24px clamp(32px, 6vw, 72px);
  margin: 40px 0 0;
  padding: 24px 0 0;
  border-top: 1px solid var(--rule);
  list-style: none;
}

.page-about .about-facts li {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.page-about .about-facts b {
  font-family: var(--font-mono);
  font-size: clamp(1.375rem, 2.4vw, 1.75rem);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  color: var(--paper);
  line-height: 1.1;
}

.page-about .about-facts span {
  font-size: var(--fs-small);
  color: var(--fog);
}

/* 章节骨架 */
.page-about .about-section {
  padding-top: var(--about-space);
  border-top: 1px solid var(--rule);
}

.page-about .index-num {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: var(--fs-small);
  letter-spacing: 0.18em;
  color: var(--fog);
}

.page-about h2 {
  margin: 14px 0 0;
  font-size: clamp(2rem, 4.4vw, 3.5rem);
  line-height: 1.12;
  letter-spacing: -0.02em;
  font-weight: 900;
  max-width: 16em;
}

.page-about h3 {
  margin: 0 0 10px;
  font-size: var(--fs-h3);
  line-height: 1.4;
  font-weight: 700;
  color: var(--paper);
}

.page-about p {
  margin: 20px 0 0;
  max-width: 34em;
  color: var(--fog);
}

.page-about h2 + p,
.page-about .about-sub {
  margin-top: 24px;
}

.page-about .about-inline-link {
  margin-top: 32px;
  font-size: var(--fs-small);
  color: var(--fog);
}

.page-about a {
  color: var(--paper);
  text-decoration: underline;
  text-decoration-color: var(--fox);
  text-decoration-thickness: 1px;
  text-underline-offset: 4px;
  transition: color var(--dur) var(--ease), text-decoration-color var(--dur) var(--ease);
}

.page-about a:hover {
  color: var(--fox);
}

.page-about a:focus-visible {
  outline: 2px solid var(--fox);
  outline-offset: 2px;
}

/* 三条内容线 */
.page-about .about-lines {
  margin-top: 40px;
}

.page-about .about-line {
  padding: 28px 0 28px 20px;
  border-left: 2px solid var(--rule);
  border-bottom: 1px solid var(--rule);
}

.page-about .about-line:first-child {
  border-top: 1px solid var(--rule);
}

.page-about .about-line--data {
  border-left-color: var(--steppe);
}

.page-about .about-line--video {
  border-left-color: var(--night);
}

.page-about .about-line--column {
  border-left-color: var(--gold);
}

.page-about .about-line__k {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: var(--fs-note);
  letter-spacing: 0.22em;
  color: var(--fog);
}

.page-about .about-line p {
  margin-top: 0;
}

/* 场馆字段 */
.page-about .about-fields {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-fields li {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 8px 24px;
  padding: 14px 0;
  border-bottom: 1px solid var(--rule);
}

.page-about .about-fields li:first-child {
  border-top: 1px solid var(--rule);
}

.page-about .about-fields__k {
  color: var(--paper);
  font-weight: 500;
}

.page-about .about-fields__v {
  color: var(--fog);
  font-size: var(--fs-small);
}

/* 图片 */
.page-about .about-figure {
  margin: 40px 0 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  border-radius: var(--radius);
  background-color: var(--ink-2);
}

.page-about .about-figure figcaption {
  margin-top: 12px;
  font-size: var(--fs-note);
  line-height: 1.6;
  letter-spacing: 0.06em;
  color: var(--fog);
}

/* 年份轴 */
.page-about .about-yearnav {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 32px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-yearnav a {
  display: inline-block;
  padding: 6px 14px;
  font-family: var(--font-mono);
  font-size: var(--fs-small);
  letter-spacing: 0.08em;
  color: var(--fog);
  text-decoration: none;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.page-about .about-yearnav a:hover {
  color: var(--paper);
  border-color: var(--fox);
  background-color: var(--hover);
}

.page-about .about-years-wrap {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 40px;
  margin-top: 40px;
}

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

.page-about .about-year {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  padding: 32px 0;
  border-top: 1px solid var(--rule);
}

.page-about .about-year:last-child {
  border-bottom: 1px solid var(--rule);
}

.page-about .about-year__num {
  font-family: var(--font-mono);
  font-size: clamp(1.75rem, 4vw, 2.75rem);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .about-year__body p {
  margin-top: 12px;
}

.page-about .about-year--fox {
  padding: 32px 24px;
  border-top-color: var(--fox);
  border-bottom: 2px solid var(--fox);
  background-color: var(--fox);
  border-radius: var(--radius);
}

.page-about .about-year--fox .about-year__num,
.page-about .about-year--fox h3 {
  color: var(--ink);
}

.page-about .about-year--fox p {
  color: var(--ink);
  opacity: 0.86;
}

/* 团队 */
.page-about .about-team {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 32px;
  margin-top: 36px;
}

.page-about .about-roles {
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-roles li {
  padding: 14px 0;
  border-top: 1px solid var(--rule);
  color: var(--fog);
  font-size: var(--fs-small);
  line-height: 1.8;
}

.page-about .about-roles li:last-child {
  border-bottom: 1px solid var(--rule);
}

.page-about .about-roles b {
  display: block;
  margin-bottom: 4px;
  color: var(--paper);
  font-size: var(--fs-body);
  font-weight: 700;
}

.page-about .about-team .about-figure {
  margin-top: 0;
}

/* 折叠 */
.page-about .about-details {
  border-bottom: 1px solid var(--rule);
}

.page-about .about-details:first-of-type {
  margin-top: 32px;
  border-top: 1px solid var(--rule);
}

.page-about .about-details summary {
  position: relative;
  padding: 20px 40px 20px 0;
  cursor: pointer;
  list-style: none;
  font-size: 1.0625rem;
  font-weight: 700;
  line-height: 1.5;
  color: var(--paper);
  transition: color var(--dur) var(--ease);
}

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

.page-about .about-details summary:hover {
  color: var(--fox);
}

.page-about .about-details summary:focus-visible {
  outline: 2px solid var(--fox);
  outline-offset: 2px;
}

.page-about .about-details summary::after {
  content: "+";
  position: absolute;
  right: 4px;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-mono);
  font-size: 1.25rem;
  line-height: 1;
  color: var(--fox);
}

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

.page-about .about-details p {
  margin: 0;
  padding: 0 0 24px;
  max-width: 34em;
  color: var(--fog);
  font-size: var(--fs-small);
  line-height: 1.9;
}

/* 合作 */
.page-about .about-coop {
  margin: 32px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-coop li {
  padding: 20px 0 20px 20px;
  border-left: 2px solid var(--rule);
  border-bottom: 1px solid var(--rule);
  color: var(--fog);
  font-size: var(--fs-small);
  line-height: 1.85;
}

.page-about .about-coop li:first-child {
  border-top: 1px solid var(--rule);
}

.page-about .about-coop b {
  display: block;
  margin-bottom: 6px;
  color: var(--paper);
  font-size: 1.0625rem;
  font-weight: 700;
}

.page-about .about-cta {
  margin-top: 40px;
}

.page-about .about-cta p {
  margin-top: 0;
}

.page-about .about-cta .btn {
  margin-top: 20px;
  text-decoration: none;
}

/* 平板及以上 */
@media (min-width: 640px) {
  .page-about .about-fields {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    column-gap: 40px;
  }

  .page-about .about-fields li:nth-child(2) {
    border-top: 1px solid var(--rule);
  }
}

@media (min-width: 720px) {
  .page-about .about-year {
    grid-template-columns: minmax(0, 150px) minmax(0, 1fr);
    column-gap: 32px;
    align-items: start;
  }

  .page-about .about-year__num {
    padding-top: 2px;
  }
}

@media (min-width: 860px) {
  .page-about .about-team {
    grid-template-columns: minmax(0, 1fr) 300px;
    column-gap: 48px;
    align-items: start;
  }
}

/* 桌面：左侧 88px 纵向栏 */
@media (min-width: 900px) {
  .page-about .about-frame {
    grid-template-columns: var(--about-rail) minmax(0, var(--about-measure));
    column-gap: clamp(24px, 3vw, 48px);
  }

  .page-about .about-rail {
    display: block;
    align-self: start;
    position: sticky;
    top: 112px;
  }

  .page-about .about-rail__text {
    display: block;
    padding-left: 12px;
    border-left: 1px solid var(--rule);
    writing-mode: vertical-rl;
    font-family: var(--font-mono);
    font-size: var(--fs-note);
    letter-spacing: 0.24em;
    color: var(--fog);
  }
}

@media (min-width: 1000px) {
  .page-about .about-years-wrap {
    grid-template-columns: minmax(0, 1fr) 260px;
    column-gap: 48px;
    align-items: start;
  }

  .page-about .about-figure--square {
    position: sticky;
    top: 112px;
    margin-top: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about a,
  .page-about .about-yearnav a,
  .page-about .about-details summary {
    transition: none;
  }
}
<<<END>>>