.page-about {
  --ab-rail: 200px;
  --ab-gap: clamp(30px, 5vw, 78px);
  --ab-radius: 14px;
  padding-bottom: clamp(60px, 10vw, 140px);
  color: var(--c-body);
}

.page-about .breadcrumb {
  padding-top: clamp(18px, 3vw, 32px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: clamp(24px, 5vw, 64px) 0 clamp(34px, 6vw, 78px);
  border-bottom: 1px solid var(--c-line);
}

.page-about .about-h1 {
  margin: 14px 0 22px;
  max-width: 19ch;
  font-size: clamp(30px, 6.4vw, 66px);
  font-weight: 200;
  line-height: 1.14;
  letter-spacing: -0.012em;
  color: var(--c-white);
}

.page-about .about-lede {
  margin: 0;
  max-width: 60ch;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
}

.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 32px 0 0;
  padding: 0;
  list-style: none;
  background: var(--c-line);
  border: 1px solid var(--c-line);
  border-radius: var(--ab-radius);
  overflow: hidden;
}

.page-about .about-stats li {
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding: 16px 18px;
  background: var(--c-night);
}

.page-about .about-stats li:last-child:nth-child(odd) {
  grid-column: 1 / -1;
}

.page-about .about-stats .stat-value {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(20px, 3vw, 28px);
  line-height: 1.1;
  color: var(--c-green);
}

.page-about .about-stats .stat-label {
  font-size: 12px;
  letter-spacing: 0.05em;
  color: var(--c-muted);
}

/* ---------- 主体骨架 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--ab-gap);
  padding-top: clamp(36px, 6vw, 88px);
}

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

/* ---------- 左侧章节索引 ---------- */
.page-about .chapter-rail {
  display: none;
}

.page-about .rail-title {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--c-muted);
}

.page-about .rail-list {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.page-about .rail-link {
  display: flex;
  gap: 10px;
  align-items: baseline;
  padding: 7px 10px;
  border-radius: var(--radius);
  font-size: 13px;
  line-height: 1.45;
  text-decoration: none;
  color: var(--c-muted);
  transition: color 180ms var(--ease), background-color 180ms var(--ease);
}

.page-about .rail-code {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.08em;
  color: var(--c-line-strong);
  transition: color 180ms var(--ease);
}

.page-about .rail-link:hover {
  color: var(--c-white);
  background: var(--s-white);
}

.page-about .rail-link[aria-current="true"] {
  color: var(--c-green);
  background: var(--s-green);
}

.page-about .rail-link[aria-current="true"] .rail-code {
  color: var(--c-green);
}

/* ---------- 章节通用 ---------- */
.page-about .ab-sec {
  padding: clamp(32px, 5.5vw, 68px) 0;
  border-top: 1px solid var(--c-line);
  scroll-margin-top: calc(var(--header-h) + 24px);
}

.page-about .about-flow > .ab-sec:first-child {
  padding-top: 0;
  border-top: 0;
}

.page-about .index-num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--c-orange);
}

.page-about .headline {
  margin: 12px 0 22px;
  max-width: 27ch;
  font-size: clamp(22px, 3.6vw, 36px);
  font-weight: 600;
  line-height: 1.3;
  letter-spacing: -0.006em;
  color: var(--c-white);
}

.page-about .prose p {
  margin: 0 0 15px;
  line-height: 1.8;
}

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

.page-about .prose strong {
  color: var(--c-white);
  font-weight: 700;
}

.page-about .ab-note {
  margin: 26px 0 0;
  max-width: 66ch;
  padding-left: 16px;
  border-left: 2px solid var(--c-line-strong);
  font-size: 14px;
  line-height: 1.78;
  color: var(--c-muted);
}

/* ---------- 图片 ---------- */
.page-about .ab-figure {
  position: relative;
  margin: 28px 0 0;
  overflow: hidden;
  border: 1px solid var(--c-line);
  border-radius: var(--ab-radius);
  background: var(--c-panel);
}

.page-about .ab-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: brightness(0.66) saturate(0.92);
}

.page-about .ab-figure::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background:
    linear-gradient(152deg, rgba(7, 12, 22, 0) 34%, rgba(7, 12, 22, 0.88) 100%),
    linear-gradient(0deg, rgba(198, 255, 61, 0.05), rgba(77, 225, 255, 0.05));
}

.page-about .ab-figure figcaption {
  padding: 12px 16px;
  border-top: 1px solid var(--c-line);
  background: var(--c-panel);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--c-muted);
}

.page-about .ab-banner img {
  aspect-ratio: 16 / 7;
}

/* ---------- 赛季时间轴 ---------- */
.page-about .ab-timeline {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: clamp(24px, 4vw, 44px);
  margin: clamp(34px, 5vw, 56px) 0 0;
  padding: 0 0 0 26px;
  list-style: none;
}

.page-about .ab-timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: linear-gradient(180deg, var(--s-green-line), var(--c-line) 62%, transparent);
}

.page-about .ab-stage {
  position: relative;
}

.page-about .ab-stage::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 7px;
  width: 11px;
  height: 11px;
  border-radius: 2px;
  background: var(--c-green);
  box-shadow: 0 0 0 4px var(--s-green);
  transition: background-color 200ms var(--ease), box-shadow 200ms var(--ease);
}

.page-about .ab-stage:hover::before {
  background: var(--c-orange);
  box-shadow: 0 0 0 4px var(--s-orange);
}

.page-about .ab-stage-code {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--c-ice);
}

.page-about .ab-stage h3 {
  margin: 7px 0 8px;
  font-size: clamp(16px, 2.1vw, 20px);
  font-weight: 600;
  line-height: 1.45;
  color: var(--c-white);
}

.page-about .ab-stage p {
  margin: 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.78;
}

/* ---------- 折线图 ---------- */
.page-about .ab-chart {
  margin: clamp(34px, 5vw, 56px) 0 0;
  padding: 20px 18px 12px;
  border: 1px solid var(--c-line);
  border-radius: var(--ab-radius);
  background: linear-gradient(180deg, rgba(14, 21, 38, 0.92), rgba(7, 12, 22, 0.62));
}

.page-about .ab-chart-cap {
  margin-bottom: 12px;
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--c-muted);
}

.page-about .ab-chart svg {
  display: block;
  width: 100%;
  height: auto;
  overflow: visible;
}

.page-about .chart-grid {
  stroke: var(--c-line);
  stroke-width: 1;
}

.page-about .chart-line {
  fill: none;
  stroke: var(--c-green);
  stroke-width: 1.5;
  stroke-linejoin: round;
  stroke-linecap: round;
}

.page-about .chart-dot--start,
.page-about .chart-dot--mid {
  fill: var(--c-night);
  stroke: var(--c-green);
  stroke-width: 1.5;
}

.page-about .chart-dot--last {
  fill: var(--c-green);
  stroke: var(--c-green);
  stroke-width: 1.5;
}

.page-about .chart-label {
  fill: var(--c-muted);
  font-family: var(--font-mono);
  font-size: 11px;
}

/* ---------- 图文并排（家庭观赛） ---------- */
.page-about .ab-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 4vw, 44px);
  align-items: center;
}

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

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

.page-about .ab-points li {
  position: relative;
  padding-left: 20px;
  font-size: 15px;
  line-height: 1.75;
}

.page-about .ab-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.68em;
  width: 9px;
  height: 1.5px;
  border-radius: 1px;
  background: var(--c-ice);
}

.page-about .ab-points strong {
  color: var(--c-white);
  font-weight: 600;
}

/* ---------- 团队分工 ---------- */
.page-about .ab-team-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 4vw, 38px);
  align-items: start;
  margin-top: 8px;
}

.page-about .ab-team-cards {
  display: grid;
  gap: 14px;
}

.page-about .ab-dossier {
  position: relative;
  padding: 18px 20px 19px 22px;
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  background: linear-gradient(180deg, rgba(14, 21, 38, 0.94), rgba(14, 21, 38, 0.52));
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.03);
  transition: border-color 200ms var(--ease), transform 200ms var(--ease);
}

.page-about .ab-dossier::before {
  content: "";
  position: absolute;
  left: 0;
  top: 16px;
  bottom: 16px;
  width: 2px;
  border-radius: 2px;
  background: var(--c-line-strong);
  transition: background-color 200ms var(--ease);
}

.page-about .ab-dossier:hover {
  border-color: var(--s-green-line);
  transform: translateY(-2px);
}

.page-about .ab-dossier:hover::before {
  background: var(--c-green);
}

.page-about .ab-dossier-code {
  position: absolute;
  top: 14px;
  right: 16px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--c-muted);
}

.page-about .ab-dossier h3 {
  margin: 0 46px 8px 0;
  font-size: 16px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--c-white);
}

.page-about .ab-dossier p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
}

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

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

/* ---------- 协作生态色带 ---------- */
.page-about .ab-band {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: 6px;
  background: var(--c-line);
  border: 1px solid var(--c-line);
  border-radius: var(--ab-radius);
  overflow: hidden;
}

.page-about .ab-band-cell {
  padding: clamp(20px, 3vw, 34px);
  background: linear-gradient(158deg, rgba(14, 21, 38, 0.96), rgba(7, 12, 22, 0.88));
}

.page-about .ab-band-num {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(30px, 5vw, 46px);
  line-height: 1;
}

.page-about .ab-band-num--green {
  color: var(--c-green);
}

.page-about .ab-band-num--orange {
  color: var(--c-orange);
}

.page-about .ab-band-cell h3 {
  margin: 0 0 10px;
  font-size: 16px;
  font-weight: 600;
  color: var(--c-white);
}

.page-about .ab-band-cell p {
  margin: 0;
  max-width: 46ch;
  font-size: 14px;
  line-height: 1.78;
}

/* ---------- 栏目体系 ---------- */
.page-about .ab-programs {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: 6px;
}

.page-about .ab-program {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 22px 20px;
  border: 1px solid var(--c-line);
  border-radius: var(--ab-radius);
  background: var(--c-panel);
  transition: border-color 200ms var(--ease), transform 200ms var(--ease);
}

.page-about .ab-program:hover {
  border-color: var(--s-green-line);
  transform: translateY(-2px);
}

.page-about .ab-program .tag {
  align-self: flex-start;
}

.page-about .ab-program h3 {
  margin: 0;
  font-size: 17px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--c-white);
}

.page-about .ab-program p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
}

/* ---------- 行业认可 ---------- */
.page-about .ab-quote {
  display: grid;
  gap: 16px;
  padding-left: 20px;
  border-left: 2px solid var(--c-orange);
}

.page-about .ab-quote p {
  margin: 0;
  max-width: 58ch;
  font-size: clamp(15px, 1.8vw, 17px);
  line-height: 1.85;
}

/* ---------- 行动区 ---------- */
.page-about .ab-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

/* ---------- 起点索引 ---------- */
.page-about .ab-start {
  border-top: 1px solid var(--c-line);
}

.page-about .ab-start-list {
  display: grid;
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  background: var(--c-line);
  border: 1px solid var(--c-line);
  border-radius: var(--ab-radius);
  overflow: hidden;
}

.page-about .ab-start-list a {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 14px;
  align-items: baseline;
  padding: 16px 20px;
  background: var(--c-night);
  font-size: 15px;
  color: var(--c-white);
  text-decoration: none;
  transition: background-color 180ms var(--ease), color 180ms var(--ease);
}

.page-about .ab-start-list a span {
  font-size: 13px;
  color: var(--c-muted);
}

.page-about .ab-start-list a:hover {
  background: rgba(198, 255, 61, 0.06);
  color: var(--c-green);
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-stats li:last-child:nth-child(odd) {
    grid-column: auto;
  }
}

@media (min-width: 780px) {
  .page-about .ab-programs {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .ab-figure figcaption {
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 2;
    padding: 14px 20px;
    border-top: 0;
    background: none;
  }

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

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

  .page-about .ab-team-layout {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  }
}

@media (min-width: 1024px) {
  .page-about .about-stats {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }
}

@media (min-width: 1180px) {
  .page-about .about-body {
    grid-template-columns: var(--ab-rail) minmax(0, 1fr);
  }

  .page-about .chapter-rail {
    display: block;
    align-self: start;
    position: sticky;
    top: calc(var(--header-h) + 28px);
    padding-left: 18px;
    border-left: 1px solid var(--c-line);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-dossier,
  .page-about .ab-program,
  .page-about .ab-stage::before {
    transition: none;
  }

  .page-about .ab-dossier:hover,
  .page-about .ab-program:hover {
    transform: none;
  }
}
</main>