.page-about {
  --about-pad: clamp(20px, 5vw, 48px);
  background: var(--ink-900);
  color: var(--paper);
  padding-bottom: clamp(56px, 9vw, 110px);
}

.page-about .breadcrumb {
  padding-top: clamp(18px, 3vw, 30px);
  padding-bottom: 6px;
}

.page-about .breadcrumb ol {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  font-size: 13px;
  color: var(--muted);
}

.page-about .breadcrumb li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--line);
}

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

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

.page-about .breadcrumb [aria-current="page"] {
  color: var(--paper);
}

/* ---------- 首屏：左窄右宽非对称分栏 ---------- */

.page-about .about-intro {
  display: grid;
  gap: clamp(26px, 4vw, 40px);
  padding-top: clamp(24px, 4vw, 44px);
  padding-bottom: clamp(30px, 5vw, 58px);
}

.page-about .intro-rail {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding-top: 18px;
  border-top: 2px solid var(--aqua);
  max-width: 420px;
}

.page-about .rail-note {
  margin: 0;
  font-size: 13px;
  line-height: 1.65;
  letter-spacing: 0.02em;
}

.page-about .rail-stats {
  list-style: none;
  margin: 10px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .rail-stats li {
  display: flex;
  align-items: baseline;
  gap: 12px;
}

.page-about .rail-stats .num {
  font-family: var(--font-num);
  font-size: 40px;
  line-height: 0.9;
  font-weight: 700;
  color: var(--aqua);
  letter-spacing: 0.01em;
}

.page-about .rail-unit {
  font-size: 13px;
  color: var(--muted);
  letter-spacing: 0.02em;
}

.page-about .intro-body h1 {
  font-size: clamp(32px, 6.4vw, 62px);
  line-height: 1.1;
  font-weight: 900;
  letter-spacing: -0.015em;
  margin: 0 0 20px;
}

.page-about .lede {
  font-size: clamp(16px, 2.2vw, 18px);
  line-height: 1.85;
  color: var(--paper);
  opacity: 0.92;
  margin: 0;
  max-width: 40em;
}

/* ---------- 通用节与导语 ---------- */

.page-about .section {
  padding-top: clamp(44px, 7vw, 92px);
}

.page-about .section-head {
  max-width: 46em;
  margin-bottom: clamp(22px, 3.4vw, 40px);
}

.page-about .section-head h2 {
  font-size: clamp(25px, 4vw, 40px);
  line-height: 1.2;
  font-weight: 800;
  letter-spacing: -0.01em;
  margin: 10px 0 14px;
}

.page-about .section-head .prose {
  margin: 0;
}

.page-about .prose {
  font-size: 16px;
  line-height: 1.85;
  color: var(--muted);
  max-width: 40em;
}

/* ---------- 日常内容 ---------- */

.page-about .daily-grid {
  display: grid;
  gap: 14px;
}

.page-about .daily-card {
  padding: 22px 22px 26px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  background: var(--ink-800);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
}

.page-about .daily-card .band {
  width: 56px;
  height: 4px;
  border-radius: 2px;
}

.page-about .daily-card h3 {
  font-size: 20px;
  font-weight: 800;
  margin: 6px 0 0;
}

.page-about .daily-card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .daily-figures {
  list-style: none;
  margin: 22px 0 0;
  padding: 20px 0 0;
  border-top: 1px solid var(--line);
  display: grid;
  gap: 16px;
}

.page-about .daily-figures li {
  display: flex;
  align-items: baseline;
  gap: 12px;
  font-size: 14px;
  line-height: 1.6;
  color: var(--muted);
}

.page-about .daily-figures .num {
  font-family: var(--font-num);
  font-size: 36px;
  line-height: 1;
  font-weight: 700;
  color: var(--amber);
}

/* ---------- 阶梯时间轴 ---------- */

.page-about .timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  position: relative;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 15px;
  top: 16px;
  bottom: 16px;
  width: 1px;
  background: linear-gradient(180deg, var(--aqua), var(--line) 38%, var(--line));
  opacity: 0.72;
}

.page-about .tl-node {
  position: relative;
  padding-left: 46px;
}

.page-about .tl-node::before {
  content: "";
  position: absolute;
  left: 10px;
  top: 22px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--ink-900);
  border: 2px solid var(--aqua);
}

.page-about .tl-node details {
  border-bottom: 1px solid var(--line);
}

.page-about .tl-node summary {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 16px 4px 16px 0;
  cursor: pointer;
  list-style: none;
}

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

.page-about .tl-idx {
  font-family: var(--font-num);
  font-size: 22px;
  line-height: 1;
  color: var(--aqua);
  letter-spacing: 0.04em;
  flex: none;
}

.page-about .tl-title {
  font-size: 17px;
  font-weight: 700;
  line-height: 1.5;
  flex: 1;
  min-width: 0;
}

.page-about .tl-node summary::after {
  content: "+";
  font-family: var(--font-num);
  font-size: 22px;
  line-height: 1;
  color: var(--muted);
  flex: none;
  transition: color 180ms ease;
}

.page-about .tl-node details[open] summary::after {
  content: "−";
  color: var(--aqua);
}

.page-about .tl-node summary:focus-visible {
  outline: 2px solid var(--aqua);
  outline-offset: 2px;
  border-radius: 6px;
}

.page-about .tl-body {
  padding: 0 4px 20px 48px;
}

.page-about .tl-body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--muted);
  max-width: 40em;
}

/* ---------- 团队 ---------- */

.page-about .team-media {
  margin: 0 0 clamp(26px, 4vw, 44px);
}

.page-about .team-media figcaption {
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.6;
}

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

.page-about .tree-root > .tree-label {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 21px;
  font-weight: 800;
  color: var(--paper);
  margin: 0;
}

.page-about .tree-root > .tree-label::before {
  content: "";
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--aqua);
  box-shadow: 0 0 0 4px rgba(43, 232, 208, 0.14);
  flex: none;
}

.page-about .tree ul {
  list-style: none;
  margin: 16px 0 0;
  padding: 0 0 0 16px;
  border-left: 1px solid var(--line);
  display: grid;
  gap: 16px;
}

.page-about .tree ul > .tree-node {
  position: relative;
  padding-left: 16px;
}

.page-about .tree ul > .tree-node::before {
  content: "";
  position: absolute;
  left: -16px;
  top: 11px;
  width: 16px;
  height: 1px;
  background: var(--line);
}

.page-about .tree ul > .tree-node .tree-label {
  margin: 0;
  font-size: 16px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .tree-desc {
  margin: 6px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--muted);
  max-width: 40em;
}

/* ---------- 内容质量 ---------- */

.page-about .quality-grid {
  display: grid;
  gap: 26px;
}

.page-about .quality-copy h2 {
  font-size: clamp(25px, 4vw, 38px);
  line-height: 1.2;
  font-weight: 800;
  letter-spacing: -0.01em;
  margin: 10px 0 14px;
}

.page-about .quality-copy .prose {
  margin: 0;
}

.page-about .check-list {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .check-list li {
  position: relative;
  padding-left: 24px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--paper);
}

.page-about .check-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 12px;
  height: 2px;
  border-radius: 1px;
  background: var(--aqua);
}

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

/* ---------- 合作与认可 ---------- */

.page-about .league-matrix {
  display: grid;
  gap: 20px;
}

.page-about .league-col {
  border-top: 3px solid var(--line);
  padding-top: 14px;
}

.page-about .league-col--foot {
  border-top-color: var(--foot);
}

.page-about .league-col--basket {
  border-top-color: var(--basket);
}

.page-about .league-col--tennis {
  border-top-color: var(--tennis);
}

.page-about .league-col h3 {
  font-size: 18px;
  font-weight: 800;
  margin: 0 0 8px;
}

.page-about .league-col p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .partners-media {
  margin: clamp(24px, 4vw, 40px) 0 0;
}

.page-about .honor-list {
  list-style: none;
  margin: clamp(20px, 3vw, 32px) 0 0;
  padding: 0;
}

.page-about .honor-list li {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 16px 0;
  border-top: 1px solid var(--line);
  font-size: 15px;
  line-height: 1.75;
  color: var(--paper);
}

.page-about .honor-list li::before {
  content: "—";
  font-family: var(--font-num);
  color: var(--aqua);
  flex: none;
}

/* ---------- 下一步入口 ---------- */

.page-about .next-links {
  display: grid;
  gap: 14px;
}

.page-about .next-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 20px 22px;
  text-decoration: none;
  color: var(--paper);
  background: var(--ink-800);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  transition: border-color 180ms ease, background-color 180ms ease;
}

.page-about .next-card:hover,
.page-about .next-card:focus-visible {
  border-color: var(--aqua);
  background: var(--raise);
}

.page-about .next-main {
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-width: 0;
}

.page-about .next-kicker {
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--aqua);
}

.page-about .next-title {
  font-size: 16px;
  font-weight: 700;
  line-height: 1.55;
}

.page-about .next-arrow {
  font-family: var(--font-num);
  font-size: 22px;
  line-height: 1;
  color: var(--muted);
  flex: none;
  transition: color 180ms ease;
}

.page-about .next-card:hover .next-arrow,
.page-about .next-card:focus-visible .next-arrow {
  color: var(--amber);
}

/* ---------- 响应式 ---------- */

@media (min-width: 720px) {
  .page-about .daily-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
  }

  .page-about .daily-figures {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 24px;
  }

  .page-about .league-matrix {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 24px;
  }

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

@media (min-width: 960px) {
  .page-about .about-intro {
    grid-template-columns: minmax(220px, 4fr) minmax(0, 8fr);
    gap: clamp(36px, 5vw, 76px);
    align-items: start;
  }

  .page-about .quality-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: clamp(28px, 4vw, 60px);
    align-items: start;
  }

  .page-about .tl-node {
    padding-left: 62px;
  }

  .page-about .timeline::before {
    left: 19px;
  }

  .page-about .tl-node::before {
    left: 14px;
  }

  .page-about .tl-body {
    padding-left: 62px;
  }

  .page-about .tl-title {
    font-size: 18px;
  }
}
<<<END>>>