.page-about {
  --ab-gutter: clamp(20px, 4vw, 56px);
  --ab-max: 1240px;
  display: block;
  background: var(--pitch-900);
  color: var(--mist-100);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  padding-bottom: clamp(56px, 8vw, 104px);
  -webkit-font-smoothing: antialiased;
}

.page-about *,
.page-about *::before,
.page-about *::after {
  box-sizing: border-box;
}

.page-about .ab-crumb,
.page-about .ab-hero,
.page-about .ab-shell {
  width: 100%;
  max-width: var(--ab-max);
  margin-inline: auto;
  padding-inline: var(--ab-gutter);
}

.page-about .ab-inner {
  width: 100%;
  max-width: var(--ab-max);
  margin-inline: auto;
  padding-inline: var(--ab-gutter);
}

.page-about .ab-visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

/* 面包屑 */
.page-about .ab-crumb {
  padding-top: 24px;
}

.page-about .ab-crumb ol {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--mist-600);
}

.page-about .ab-crumb li + li::before {
  content: "/";
  margin-right: 6px;
  color: var(--line-600);
}

.page-about .ab-crumb a {
  color: var(--mist-400);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 160ms ease, border-color 160ms ease;
}

.page-about .ab-crumb a:hover,
.page-about .ab-crumb a:focus-visible {
  color: var(--cyan-400);
  border-bottom-color: var(--cyan-400);
}

/* 首屏 */
.page-about .ab-hero {
  display: grid;
  gap: clamp(28px, 4vw, 48px);
  padding-top: clamp(28px, 4vw, 52px);
  padding-bottom: clamp(36px, 6vw, 72px);
}

.page-about .ab-eyebrow {
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--cyan-400);
}

.page-about .ab-title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.05;
  font-size: clamp(30px, 5.2vw, 58px);
  color: var(--mist-100);
}

.page-about .ab-lead {
  margin: 20px 0 0;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.8;
  color: var(--mist-400);
}

.page-about .ab-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
  align-items: center;
}

.page-about .ab-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  border: 1px solid var(--line-600);
  background: transparent;
  color: var(--mist-100);
  cursor: pointer;
  transition: color 160ms ease, background-color 160ms ease, border-color 160ms ease;
}

.page-about .ab-btn--solid {
  background: var(--cyan-400);
  border-color: var(--cyan-400);
  color: var(--pitch-900);
}

.page-about .ab-btn--solid:hover {
  background: var(--mist-100);
  border-color: var(--mist-100);
}

.page-about .ab-btn--ghost:hover {
  border-color: var(--cyan-400);
  color: var(--cyan-400);
}

.page-about .ab-btn:focus-visible,
.page-about .ab-link:focus-visible {
  outline: 2px solid var(--cyan-400);
  outline-offset: 2px;
}

.page-about .ab-facts {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 28px;
  margin: 30px 0 0;
  padding: 18px 0 0;
  list-style: none;
  border-top: 1px solid var(--line-600);
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--mist-400);
}

.page-about .ab-facts b {
  color: var(--cyan-400);
  font-weight: 700;
}

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

.page-about .ab-hero__media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  border-radius: var(--radius-l);
  border: 1px solid var(--line-600);
}

.page-about .ab-hero__media figcaption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--mist-600);
}

/* 横向赛季带 */
.page-about .ab-band {
  margin-top: clamp(8px, 2vw, 24px);
  background: var(--pitch-800);
  border-top: 1px solid var(--line-600);
  border-bottom: 1px solid var(--line-600);
  padding-block: clamp(40px, 6vw, 76px);
}

.page-about .ab-band__head {
  display: grid;
  gap: 14px;
  margin-bottom: clamp(28px, 4vw, 44px);
}

.page-about .ab-band__scroll {
  overflow-x: auto;
  overflow-y: hidden;
  padding-bottom: 6px;
  scrollbar-color: var(--line-600) transparent;
}

.page-about .ab-band__track {
  display: grid;
  grid-template-columns: repeat(7, minmax(128px, 1fr));
  min-width: 900px;
  margin: 0;
  padding: 0 0 76px;
  list-style: none;
  border-top: 1px solid var(--line-600);
}

.page-about .ab-node {
  position: relative;
  border-left: 1px solid var(--line-600);
  padding: 26px 14px 0;
  transition: border-color 160ms ease;
}

.page-about .ab-node:hover,
.page-about .ab-node:focus-visible {
  border-left-color: var(--cyan-400);
  outline: none;
}

.page-about .ab-node:focus-visible {
  outline: 2px solid var(--cyan-400);
  outline-offset: -2px;
}

.page-about .ab-node__dot {
  position: absolute;
  top: -5px;
  left: -5px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--cyan-400);
  border: 2px solid var(--pitch-800);
}

.page-about .ab-node--now .ab-node__dot {
  background: var(--amber-500);
  box-shadow: 0 0 0 4px rgba(255, 176, 58, 0.18);
}

.page-about .ab-node__idx {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--cyan-400);
  font-variant-numeric: tabular-nums;
}

.page-about .ab-node--now .ab-node__idx {
  color: var(--amber-500);
}

.page-about .ab-node__name {
  display: block;
  margin-top: 8px;
  font-size: 15px;
  font-weight: 600;
  color: var(--mist-100);
}

.page-about .ab-node__stage {
  display: block;
  margin-top: 4px;
  font-size: 12px;
  line-height: 1.6;
  color: var(--mist-600);
}

.page-about .ab-node__tip {
  position: absolute;
  top: calc(100% + 28px);
  left: 14px;
  z-index: 4;
  padding: 8px 12px;
  border-radius: var(--radius-m);
  background: var(--pitch-700);
  border: 1px solid var(--line-600);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.02em;
  color: var(--mist-100);
  white-space: nowrap;
  opacity: 0;
  transform: translateY(-4px);
  transition: opacity 160ms ease, transform 160ms ease;
}

.page-about .ab-node:last-child .ab-node__tip {
  left: auto;
  right: 14px;
}

.page-about .ab-node:hover .ab-node__tip,
.page-about .ab-node:focus-visible .ab-node__tip,
.page-about .ab-node:focus-within .ab-node__tip {
  opacity: 1;
  transform: translateY(0);
}

/* 主体骨架 */
.page-about .ab-shell {
  display: grid;
  gap: clamp(28px, 4vw, 56px);
  padding-top: clamp(40px, 6vw, 76px);
}

.page-about .ab-index__title {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--mist-600);
}

.page-about .ab-index ol {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 4px;
  list-style: none;
  overflow-x: auto;
}

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

.page-about .ab-index a {
  display: block;
  padding: 6px 12px;
  font-size: 13px;
  color: var(--mist-400);
  text-decoration: none;
  white-space: nowrap;
  border: 1px solid var(--line-600);
  border-radius: 999px;
  transition: color 160ms ease, background-color 160ms ease, border-color 160ms ease;
}

.page-about .ab-index a:hover,
.page-about .ab-index a:focus-visible {
  color: var(--pitch-900);
  background: var(--cyan-400);
  border-color: var(--cyan-400);
  outline: none;
}

/* 章节 */
.page-about .ab-section {
  padding-block: clamp(44px, 6vw, 88px);
  border-top: 1px solid var(--line-600);
}

.page-about .ab-section:first-child {
  padding-top: 0;
  border-top: 0;
}

.page-about .ab-section--last {
  padding-bottom: 0;
}

.page-about .ab-h2 {
  margin: 0 0 20px;
  font-family: var(--font-display);
  font-weight: 700;
  letter-spacing: -0.01em;
  line-height: 1.18;
  font-size: clamp(24px, 3.2vw, 36px);
  color: var(--mist-100);
}

.page-about .ab-h3 {
  margin: 0 0 12px;
  font-size: 17px;
  font-weight: 700;
  color: var(--mist-100);
}

.page-about .ab-p {
  margin: 0 0 16px;
  max-width: 68ch;
  font-size: 15px;
  line-height: 1.85;
  color: var(--mist-400);
}

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

.page-about .ab-p--after {
  margin-top: 24px;
}

.page-about .ab-link {
  color: var(--cyan-400);
  text-decoration: none;
  border-bottom: 1px solid var(--line-600);
  transition: border-color 160ms ease;
}

.page-about .ab-link:hover {
  border-bottom-color: var(--cyan-400);
}

.page-about .ab-mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

.page-about .ab-mono--cyan {
  color: var(--cyan-400);
}

/* 三件事 */
.page-about .ab-points {
  display: grid;
  gap: 20px;
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-points li {
  padding-top: 16px;
  border-top: 1px solid var(--line-600);
}

.page-about .ab-points b {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.12em;
  color: var(--cyan-400);
}

.page-about .ab-points span {
  display: block;
  font-size: 15px;
  line-height: 1.8;
  color: var(--mist-400);
}

/* 联赛列表 */
.page-about .ab-leagues {
  display: grid;
  gap: 1px;
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
  background: var(--line-600);
  border: 1px solid var(--line-600);
  border-radius: var(--radius-m);
  overflow: hidden;
}

.page-about .ab-leagues li {
  display: grid;
  gap: 6px;
  padding: 16px 18px;
  background: var(--pitch-900);
  transition: background-color 180ms ease;
}

.page-about .ab-leagues li:hover {
  background: var(--pitch-800);
}

.page-about .ab-league__name {
  font-size: 16px;
  font-weight: 700;
  color: var(--mist-100);
}

.page-about .ab-league__desc {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--mist-400);
}

/* 双栏 */
.page-about .ab-split {
  display: grid;
  gap: 28px;
}

.page-about .ab-figure {
  margin: 0;
}

.page-about .ab-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  border-radius: var(--radius-m);
  border: 1px solid var(--line-600);
}

.page-about .ab-figure figcaption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--mist-600);
}

/* 规模数据 */
.page-about .ab-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1px;
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
  background: var(--line-600);
  border: 1px solid var(--line-600);
  border-radius: var(--radius-m);
  overflow: hidden;
}

.page-about .ab-stats li {
  padding: 20px 18px;
  background: var(--pitch-800);
}

.page-about .ab-stat__num {
  display: block;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(28px, 3.6vw, 42px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: 0.01em;
  color: var(--cyan-400);
}

.page-about .ab-stat__num--amber {
  color: var(--amber-500);
}

.page-about .ab-stat__label {
  display: block;
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--mist-400);
}

/* 对照表 */
.page-about .ab-table__wrap {
  margin-top: 28px;
  overflow-x: auto;
  border: 1px solid var(--line-600);
  border-radius: var(--radius-m);
}

.page-about .ab-table {
  width: 100%;
  min-width: 560px;
  border-collapse: collapse;
  font-size: 14px;
}

.page-about .ab-table th,
.page-about .ab-table td {
  padding: 14px 16px;
  text-align: left;
  border-bottom: 1px solid var(--line-600);
  vertical-align: top;
}

.page-about .ab-table thead th {
  background: var(--pitch-700);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.1em;
  color: var(--mist-400);
}

.page-about .ab-table tbody td {
  background: var(--pitch-900);
  color: var(--mist-400);
  line-height: 1.75;
}

.page-about .ab-table tbody td:first-child {
  color: var(--mist-100);
  font-weight: 600;
  white-space: nowrap;
}

.page-about .ab-table tbody tr:last-child td {
  border-bottom: 0;
}

/* 双向索引 */
.page-about .ab-cross {
  display: grid;
  gap: 16px;
  margin-top: 28px;
}

.page-about .ab-cross__panel {
  padding: 22px;
  background: var(--pitch-700);
  border: 1px solid var(--line-600);
  border-radius: var(--radius-m);
}

.page-about .ab-cross__kicker {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--cyan-400);
}

.page-about .ab-cross__panel ul {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-cross__panel li {
  padding: 5px 12px;
  font-size: 13px;
  color: var(--mist-400);
  border: 1px solid var(--line-600);
  border-radius: 999px;
}

/* 合作生态 */
.page-about .ab-partners {
  display: grid;
  gap: 1px;
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
  background: var(--line-600);
  border: 1px solid var(--line-600);
  border-radius: var(--radius-m);
  overflow: hidden;
}

.page-about .ab-partner {
  display: grid;
  gap: 6px;
  padding: 18px 20px;
  background: var(--pitch-800);
  transition: background-color 180ms ease;
}

.page-about .ab-partner:hover,
.page-about .ab-partner:focus-visible {
  background: var(--pitch-700);
  outline: none;
}

.page-about .ab-partner:focus-visible {
  box-shadow: inset 0 0 0 2px var(--cyan-400);
}

.page-about .ab-partner__num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--amber-500);
}

.page-about .ab-partner__name {
  font-size: 15px;
  font-weight: 600;
  color: var(--mist-100);
}

.page-about .ab-partner__desc {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--mist-400);
  opacity: 0.72;
  transition: opacity 200ms ease;
}

.page-about .ab-partner:hover .ab-partner__desc,
.page-about .ab-partner:focus-visible .ab-partner__desc {
  opacity: 1;
}

/* 联系 */
.page-about .ab-contact-card {
  padding: clamp(24px, 4vw, 40px);
  background: var(--pitch-800);
  border: 1px solid var(--line-600);
  border-radius: var(--radius-l);
}

.page-about .ab-copy {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 10px 18px;
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--cyan-400);
  background: transparent;
  border: 1px dashed var(--line-600);
  border-radius: 999px;
  cursor: pointer;
  transition: border-color 160ms ease, color 160ms ease;
}

.page-about .ab-copy:hover {
  border-color: var(--cyan-400);
}

.page-about .ab-copy:focus-visible {
  outline: 2px solid var(--cyan-400);
  outline-offset: 2px;
}

.page-about .ab-copy[data-copied]::after {
  content: "已复制";
  font-family: var(--font-body);
  font-size: 12px;
  color: var(--mist-400);
}

/* 平板与桌面 */
@media (min-width: 760px) {
  .page-about .ab-points {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 28px;
  }

  .page-about .ab-leagues li {
    grid-template-columns: 110px minmax(0, 1fr);
    gap: 20px;
    align-items: baseline;
    padding: 18px 22px;
  }

  .page-about .ab-cross {
    grid-template-columns: 1fr 1fr;
    gap: 20px;
  }

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

@media (min-width: 900px) {
  .page-about .ab-hero {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    align-items: end;
  }

  .page-about .ab-section {
    padding-block: clamp(56px, 6vw, 96px);
  }

  .page-about .ab-split {
    grid-template-columns: minmax(0, 320px) minmax(0, 1fr);
    gap: clamp(32px, 5vw, 64px);
    align-items: start;
  }

  .page-about .ab-split--flip {
    grid-template-columns: minmax(0, 1fr) minmax(0, 400px);
  }

  .page-about .ab-split--flip .ab-figure {
    order: 2;
  }
}

@media (min-width: 980px) {
  .page-about .ab-shell {
    grid-template-columns: 200px minmax(0, 1fr);
    align-items: start;
  }

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

  .page-about .ab-index ol {
    flex-direction: column;
    gap: 2px;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .ab-index a {
    border: 0;
    border-left: 2px solid var(--line-600);
    border-radius: 0;
    padding: 8px 12px;
    white-space: normal;
  }

  .page-about .ab-index a:hover,
  .page-about .ab-index a:focus-visible {
    background: transparent;
    color: var(--cyan-400);
    border-left-color: var(--cyan-400);
  }
}

@media (min-width: 1100px) {
  .page-about .ab-band__track {
    min-width: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition-duration: 0ms !important;
    animation-duration: 0ms !important;
  }
}