.page-about {
  --ab-rail-w: 176px;
  background: var(--snow);
  color: var(--ink);
  font-family: var(--font-sans);
}

.page-about a:focus-visible {
  outline: 2px solid var(--coral-500);
  outline-offset: 2px;
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  background-color: var(--blue-900);
  background-image:
    repeating-linear-gradient(45deg, rgba(245, 248, 250, 0.055) 0 1px, transparent 1px 18px),
    repeating-linear-gradient(-45deg, rgba(245, 248, 250, 0.055) 0 1px, transparent 1px 18px);
  color: var(--snow);
  padding: clamp(88px, 14vw, 132px) 0 clamp(40px, 6vw, 64px);
  overflow: hidden;
}

.page-about .ab-hero .breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  list-style: none;
  margin: 0 0 clamp(24px, 4vw, 40px);
  padding: 0;
  font-size: 0.78rem;
  letter-spacing: 0.06em;
}

.page-about .ab-hero .breadcrumb-item {
  color: rgba(245, 248, 250, 0.66);
}

.page-about .ab-hero .breadcrumb-item + .breadcrumb-item::before {
  content: "/";
  margin-right: 8px;
  opacity: 0.5;
}

.page-about .ab-hero .breadcrumb-item a {
  color: var(--snow);
  text-decoration: none;
  border-bottom: 1px solid rgba(245, 248, 250, 0.4);
}

.page-about .ab-hero .breadcrumb-item a:hover {
  color: var(--coral-500);
  border-bottom-color: var(--coral-500);
}

.page-about .ab-hero-grid {
  display: grid;
  gap: clamp(28px, 5vw, 48px);
}

.page-about .ab-eyebrow {
  margin: 0 0 14px;
  font-size: 0.76rem;
  font-weight: 700;
  letter-spacing: 0.2em;
  color: var(--coral-500);
}

.page-about .ab-hero h1 {
  margin: 0;
  font-size: clamp(2rem, 7.4vw, 3.5rem);
  font-weight: 900;
  line-height: 1.12;
  letter-spacing: -0.02em;
  max-width: 16em;
}

.page-about .ab-hero-deck {
  margin: 20px 0 0;
  max-width: 30em;
  font-size: clamp(0.98rem, 2.4vw, 1.08rem);
  line-height: 1.85;
  color: rgba(245, 248, 250, 0.82);
}

.page-about .ab-hero-facts {
  display: flex;
  flex-wrap: wrap;
  gap: 16px 34px;
  margin-top: clamp(24px, 4vw, 38px);
  padding-top: 18px;
  border-top: 1px solid rgba(245, 248, 250, 0.22);
}

.page-about .ab-hfact-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.5rem;
  line-height: 1.1;
  color: var(--coral-500);
}

.page-about .ab-hfact-label {
  font-size: 0.76rem;
  letter-spacing: 0.06em;
  color: rgba(245, 248, 250, 0.66);
}

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

.page-about .ab-hero-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  clip-path: polygon(0 9%, 100% 0, 100% 100%, 0 100%);
}

.page-about .ab-cap {
  margin-top: 10px;
  font-size: 0.74rem;
  line-height: 1.6;
  letter-spacing: 0.04em;
  color: rgba(245, 248, 250, 0.6);
}

/* ---------- 主体骨架 ---------- */
.page-about .ab-body {
  padding: clamp(36px, 6vw, 72px) 0 clamp(48px, 8vw, 96px);
}

.page-about .ab-layout {
  display: grid;
  gap: clamp(20px, 4vw, 32px);
}

/* ---------- 赛季轴（移动端横向） ---------- */
.page-about .ab-rail-title {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  color: var(--slate);
}

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

.page-about .ab-axis-link {
  position: relative;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 9px 12px;
  border: 1px solid var(--line);
  background: var(--snow);
  color: var(--ink);
  font-size: 0.82rem;
  text-decoration: none;
  white-space: nowrap;
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.page-about .ab-axis-num {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--blue-400);
  transition: color var(--dur) var(--ease);
}

.page-about .ab-axis-link:hover,
.page-about .ab-axis-link.is-active {
  border-color: var(--coral-500);
  color: var(--coral-500);
}

.page-about .ab-axis-link:hover .ab-axis-num,
.page-about .ab-axis-link.is-active .ab-axis-num {
  color: var(--coral-500);
}

.page-about .ab-axis-tip {
  display: none;
}

/* ---------- 章节 ---------- */
.page-about .ab-sec + .ab-sec {
  margin-top: clamp(32px, 5vw, 56px);
  padding-top: clamp(28px, 5vw, 48px);
  border-top: 1px solid var(--line);
}

.page-about .ab-sec-head {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 0 0 clamp(16px, 3vw, 24px);
}

.page-about .ab-sec-head::before {
  content: "";
  flex: 0 0 auto;
  width: 32px;
  height: 4px;
  background: var(--red-600);
}

.page-about .ab-sec-num {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.08em;
  color: var(--slate);
}

.page-about .ab-sec-title {
  margin: 0;
  font-size: clamp(1.25rem, 4.4vw, 1.85rem);
  font-weight: 900;
  line-height: 1.22;
  letter-spacing: -0.015em;
}

.page-about .ab-prose p {
  margin: 0 0 1em;
  max-width: 36em;
  font-size: 1rem;
  line-height: 1.85;
}

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

.page-about .ab-prose .ab-lead {
  font-size: clamp(1.02rem, 2.6vw, 1.14rem);
  color: var(--blue-700);
  line-height: 1.8;
}

.page-about .ab-inline-link {
  color: var(--blue-700);
  text-decoration: none;
  border-bottom: 1px solid var(--coral-200);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .ab-inline-link:hover {
  color: var(--coral-500);
  border-bottom-color: var(--coral-500);
}

/* ---------- 数据行 ---------- */
.page-about .ab-metrics {
  margin: clamp(20px, 4vw, 30px) 0 0;
  border-top: 1px solid var(--line);
}

.page-about .ab-metrics--flush {
  margin-top: 0;
}

.page-about .ab-metric {
  display: flex;
  align-items: baseline;
  gap: 16px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
  transition: color var(--dur) var(--ease);
}

.page-about .ab-metric-num {
  flex: 0 0 auto;
  min-width: 2.6em;
  font-family: var(--font-mono);
  font-size: clamp(1.45rem, 5vw, 2.2rem);
  font-weight: 500;
  line-height: 1;
  color: var(--blue-700);
  transition: color var(--dur) var(--ease);
}

.page-about .ab-metric-text {
  font-size: 0.94rem;
  line-height: 1.65;
  color: var(--slate);
  transition: color var(--dur) var(--ease);
}

.page-about .ab-metric:hover .ab-metric-num,
.page-about .ab-metric:hover .ab-metric-text {
  color: var(--coral-500);
}

/* ---------- 图片 ---------- */
.page-about .ab-figure {
  margin: clamp(20px, 4vw, 28px) 0 0;
}

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

.page-about .ab-figure--wide img {
  aspect-ratio: 3 / 2;
}

.page-about .ab-figure--square {
  max-width: 420px;
  margin-top: 0;
}

.page-about .ab-figure--square img {
  aspect-ratio: 1 / 1;
}

.page-about .ab-figure figcaption {
  margin-top: 10px;
  padding-left: 10px;
  border-left: 2px solid var(--coral-200);
  font-size: 0.78rem;
  line-height: 1.6;
  color: var(--slate);
}

/* ---------- 时间轴 ---------- */
.page-about .ab-timeline {
  display: grid;
  gap: 18px;
  margin: clamp(20px, 4vw, 28px) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-tl {
  position: relative;
  padding: 16px 0 0;
  border-top: 1px solid var(--line);
}

.page-about .ab-tl::before {
  content: "";
  position: absolute;
  top: -4px;
  left: 0;
  width: 7px;
  height: 7px;
  background: var(--red-600);
  transform: rotate(45deg);
}

.page-about .ab-tl-season {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  color: var(--red-600);
}

.page-about .ab-tl-name {
  margin: 5px 0 6px;
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.35;
}

.page-about .ab-tl-desc {
  margin: 0;
  font-size: 0.86rem;
  line-height: 1.7;
  color: var(--slate);
}

/* ---------- 收尾入口 ---------- */
.page-about .ab-next {
  margin-top: clamp(32px, 5vw, 52px);
  padding-top: clamp(24px, 4vw, 36px);
  border-top: 1px solid var(--line);
}

.page-about .ab-next-title {
  margin: 0 0 16px;
  font-size: clamp(1.15rem, 3.6vw, 1.55rem);
  font-weight: 900;
  letter-spacing: -0.01em;
}

.page-about .ab-next-links {
  display: grid;
  gap: 10px;
}

.page-about .ab-next-link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  min-height: 48px;
  padding: 14px 16px;
  border: 1px solid var(--line);
  background: var(--snow);
  color: var(--ink);
  font-size: 0.95rem;
  font-weight: 700;
  text-decoration: none;
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease),
    transform var(--dur) var(--ease);
}

.page-about .ab-next-link:hover {
  border-color: var(--coral-500);
  background: var(--ice);
  transform: translateY(-2px);
}

.page-about .ab-next-arrow {
  font-family: var(--font-mono);
  color: var(--coral-500);
}

/* ---------- 断点 ---------- */
@media (min-width: 720px) {
  .page-about .ab-timeline {
    grid-template-columns: repeat(auto-fit, minmax(148px, 1fr));
    gap: 22px 18px;
  }

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

  .page-about .ab-grid-source {
    display: grid;
    grid-template-columns: minmax(0, 220px) minmax(0, 1fr);
    gap: clamp(20px, 4vw, 36px);
    align-items: start;
    margin-top: clamp(20px, 4vw, 28px);
  }

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

  .page-about .ab-grid-source .ab-metrics {
    margin-top: 0;
  }
}

@media (min-width: 900px) {
  .page-about .ab-hero-grid {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    align-items: end;
  }

  .page-about .ab-layout {
    grid-template-columns: var(--ab-rail-w) minmax(0, 1fr);
    gap: clamp(32px, 5vw, 56px);
  }

  .page-about .ab-rail {
    position: sticky;
    top: calc(var(--header-h) + 28px);
    align-self: start;
  }

  .page-about .ab-rail-title {
    padding-left: 16px;
    border-left: 1px solid transparent;
  }

  .page-about .ab-axis {
    display: block;
    overflow: visible;
    padding-bottom: 0;
    border-left: 1px solid var(--line);
  }

  .page-about .ab-axis-link {
    display: flex;
    gap: 10px;
    padding: 10px 0 10px 16px;
    border: 0;
    background: transparent;
    white-space: normal;
    font-size: 0.85rem;
    line-height: 1.5;
  }

  .page-about .ab-axis-link::before {
    content: "";
    position: absolute;
    top: 15px;
    left: -4px;
    width: 7px;
    height: 7px;
    background: var(--blue-400);
    transform: rotate(45deg);
    transition: background var(--dur) var(--ease);
  }

  .page-about .ab-axis-link:hover::before,
  .page-about .ab-axis-link.is-active::before {
    background: var(--coral-500);
  }

  .page-about .ab-axis-link.is-active {
    color: var(--coral-500);
  }

  .page-about .ab-axis-tip {
    display: block;
    position: absolute;
    top: 4px;
    left: 100%;
    z-index: 6;
    width: 205px;
    margin-left: 12px;
    padding: 10px 12px;
    background: var(--blue-900);
    color: var(--snow);
    font-size: 0.74rem;
    line-height: 1.65;
    opacity: 0;
    visibility: hidden;
    transform: translateX(-4px);
    transition: opacity var(--dur) var(--ease), transform var(--dur) var(--ease),
      visibility var(--dur) var(--ease);
  }

  .page-about .ab-axis-link:hover .ab-axis-tip,
  .page-about .ab-axis-link:focus-visible .ab-axis-tip {
    opacity: 1;
    visibility: visible;
    transform: none;
  }

  .page-about .ab-grid-team {
    display: grid;
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
    gap: clamp(24px, 4vw, 40px);
    align-items: start;
  }

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

  .page-about .ab-prose p {
    max-width: 34em;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-axis-tip,
  .page-about .ab-next-link,
  .page-about .ab-metric,
  .page-about .ab-metric-num {
    transition: opacity var(--dur) var(--ease);
  }

  .page-about .ab-next-link:hover {
    transform: none;
  }
}