.page-about {
  background: var(--paper);
  color: var(--ink);
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  position: relative;
  padding-top: clamp(18px, 3.5vw, 36px);
  background:
    radial-gradient(120% 80% at 82% 0%, rgba(240, 174, 60, 0.16), transparent 62%),
    var(--paper);
  border-bottom: var(--bw) solid var(--ink);
}

.page-about .ab-hero .wrap {
  padding-bottom: clamp(28px, 5vw, 56px);
}

.page-about .ab-hero__kicker {
  display: inline-block;
  margin: clamp(6px, 2vw, 18px) 0 0;
  padding: 7px 14px;
  background: var(--night);
  color: var(--cyan);
  border: var(--bw) solid var(--ink);
  box-shadow: 4px 4px 0 var(--ink);
  font-size: 12px;
  line-height: 1.4;
  letter-spacing: 0.08em;
}

.page-about .ab-hero__title {
  margin: clamp(18px, 3.2vw, 30px) 0 0;
  font-size: clamp(38px, 8.6vw, 104px);
  line-height: 0.96;
  letter-spacing: -0.02em;
  font-weight: 900;
  color: var(--ink);
}

.page-about .ab-hero__mark {
  position: relative;
  display: inline-block;
  color: var(--red);
}

.page-about .ab-hero__mark::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -0.02em;
  height: 0.075em;
  background: var(--night);
  transform: skewX(-10deg);
}

.page-about .ab-hero__lede {
  max-width: 35em;
  margin: clamp(20px, 3.4vw, 32px) 0 0;
  font-size: clamp(16px, 1.7vw, 19px);
  line-height: 1.85;
  color: var(--ink);
}

.page-about .ab-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(14px, 2.5vw, 28px);
  margin: clamp(30px, 5vw, 52px) 0 0;
  padding: clamp(18px, 2.4vw, 24px) 0 0;
  list-style: none;
  border-top: var(--bw) solid var(--ink);
}

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

.page-about .ab-stats__n {
  font-family: var(--font-mono);
  font-size: clamp(24px, 3.4vw, 36px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--night);
}

.page-about .ab-stats__n em {
  font-style: normal;
  color: var(--red);
}

.page-about .ab-stats__k {
  font-size: 13px;
  line-height: 1.55;
  color: var(--muted);
}

.page-about .ab-hero__figure {
  margin: 0;
  border-top: var(--bw) solid var(--ink);
}

.page-about .ab-hero__figure .figure__media {
  aspect-ratio: 16 / 9;
  border: 0;
  box-shadow: none;
}

.page-about .ab-hero__figure .figure__caption {
  color: var(--muted);
  padding: 10px clamp(18px, 4vw, 48px) 14px;
  border-top: 1px solid var(--line);
}

/* ---------- 通用分区 ---------- */
.page-about .ab-sec {
  position: relative;
  padding: clamp(48px, 9vw, 112px) 0;
}

.page-about .ab-sec + .ab-sec {
  border-top: var(--bw) solid var(--line);
}

.page-about .ab-sec__head {
  max-width: 46rem;
  margin-bottom: clamp(28px, 5vw, 56px);
}

.page-about .ab-sec__num {
  margin: 0 0 10px;
  color: var(--red);
  font-size: 13px;
  letter-spacing: 0.1em;
}

.page-about .ab-sec__title {
  margin: 0;
  font-size: clamp(26px, 4.2vw, 44px);
  line-height: 1.22;
  font-weight: 900;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.page-about .ab-sec__sub {
  margin: 14px 0 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .ab-sec--night {
  background:
    linear-gradient(180deg, rgba(46, 224, 196, 0.08), transparent 42%),
    var(--night);
  color: var(--paper);
  border-top: var(--bw) solid var(--ink);
}

.page-about .ab-sec--night .ab-sec__title {
  color: var(--paper);
}

.page-about .ab-sec--night .ab-sec__sub {
  color: rgba(243, 236, 223, 0.74);
}

.page-about .ab-sec--night .ab-sec__num {
  color: var(--yellow);
}

/* ---------- 时间线 ---------- */
.page-about .ab-timeline__grid {
  display: grid;
  gap: clamp(24px, 4vw, 40px);
}

.page-about .ab-index__list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 8px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

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

.page-about .ab-index__link {
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 9px 14px;
  background: var(--paper);
  border: var(--bw) solid var(--line);
  color: var(--ink);
  text-decoration: none;
  white-space: nowrap;
  transition: border-color 0.18s var(--ease), color 0.18s var(--ease), transform 0.18s var(--ease), box-shadow 0.18s var(--ease);
}

.page-about .ab-index__num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--muted);
}

.page-about .ab-index__year {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.04em;
}

.page-about .ab-index__link:hover,
.page-about .ab-index__link:focus-visible {
  border-color: var(--red);
  color: var(--red);
  box-shadow: 4px 4px 0 var(--ink);
  transform: translateY(-2px);
}

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

.page-about .ab-nodes {
  display: flex;
  flex-direction: column;
  gap: clamp(28px, 5vw, 64px);
}

.page-about .tl-node {
  position: relative;
  padding: clamp(20px, 3.6vw, 40px) clamp(18px, 3.2vw, 36px) clamp(20px, 3.6vw, 40px) clamp(26px, 4vw, 48px);
  background: var(--paper);
  border: var(--bw) solid var(--ink);
  box-shadow: 8px 8px 0 var(--night);
  scroll-margin-top: clamp(90px, 14vh, 132px);
  transition: box-shadow 0.2s var(--ease), transform 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .tl-node:hover {
  transform: translateY(-2px);
  border-color: var(--red);
  box-shadow: 10px 10px 0 var(--red);
}

.page-about .tl-node:focus {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

.page-about .tl-node__stripe {
  position: absolute;
  top: -2px;
  bottom: -2px;
  left: -2px;
  width: clamp(8px, 1.6vw, 14px);
  background: linear-gradient(180deg, var(--yellow), var(--red));
  clip-path: polygon(0 0, 100% 0, 40% 100%, 0 100%);
  pointer-events: none;
}

.page-about .tl-node__head {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 14px;
}

.page-about .tl-node__year {
  font-family: var(--font-mono);
  font-size: clamp(28px, 5vw, 52px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--night);
}

.page-about .tl-node__title {
  margin: 0 0 10px;
  font-size: clamp(18px, 2.4vw, 23px);
  line-height: 1.45;
  font-weight: 700;
  color: var(--ink);
}

.page-about .tl-node__text {
  margin: 0;
  font-size: 16px;
  line-height: 1.85;
  color: var(--muted);
}

@keyframes ab-node-flash {
  0%,
  55% {
    border-color: var(--cyan);
    box-shadow: 8px 8px 0 var(--cyan);
  }
  100% {
    border-color: var(--ink);
    box-shadow: 8px 8px 0 var(--night);
  }
}

.page-about .tl-node:target {
  animation: ab-node-flash 1.5s var(--ease) both;
}

/* 时间线内的图块 */
.page-about .ab-figure {
  margin: 0;
}

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

.page-about .ab-figure .figure__caption {
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 改版章节 ---------- */
.page-about .ab-revamp {
  background:
    linear-gradient(120deg, rgba(246, 216, 206, 0.5), transparent 55%),
    var(--paper);
}

.page-about .ab-revamp__inner {
  display: grid;
  gap: clamp(20px, 3.5vw, 40px);
}

.page-about .ab-revamp__head .ab-sec__title {
  max-width: 22ch;
}

.page-about .ab-revamp__body .prose {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink);
}

.page-about .ab-steps {
  counter-reset: abstep;
  margin: 22px 0 24px;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 10px;
}

.page-about .ab-steps li {
  counter-increment: abstep;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 4px 14px;
  align-items: baseline;
  padding: 12px 16px;
  background: var(--paper-2);
  border-left: 5px solid var(--red);
}

.page-about .ab-steps li::before {
  content: counter(abstep, decimal-leading-zero);
  grid-row: 1 / 3;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--red);
  letter-spacing: 0.06em;
}

.page-about .ab-steps strong {
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .ab-steps span {
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .ab-note {
  margin: 0;
  padding: 16px 18px;
  border: var(--bw) solid var(--ink);
  border-left-width: 6px;
  border-left-color: var(--yellow);
  background: var(--red-soft);
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink);
}

/* ---------- 赛区 ---------- */
.page-about .ab-zones__grid {
  display: grid;
  gap: clamp(26px, 4vw, 48px);
}

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

.page-about .ab-zones__cell-num {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.08em;
  fill: var(--paper);
}

.page-about .ab-zones__chart-note {
  margin: 14px 0 0;
  font-size: 13px;
  line-height: 1.7;
  color: rgba(243, 236, 223, 0.72);
}

.page-about .ab-zones__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-zones__facts > li {
  padding: 16px 16px 18px;
  background: var(--night-2);
  border: var(--bw) solid rgba(243, 236, 223, 0.26);
}

.page-about .ab-zones__n {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(22px, 3vw, 32px);
  font-weight: 700;
  line-height: 1.1;
  color: var(--yellow);
}

.page-about .ab-zones__n em {
  font-style: normal;
  color: var(--cyan);
}

.page-about .ab-zones__k {
  display: block;
  margin-top: 8px;
  font-size: 13px;
  line-height: 1.6;
  color: rgba(243, 236, 223, 0.8);
}

/* ---------- 组织者 ---------- */
.page-about .ab-org__grid {
  display: grid;
  gap: clamp(26px, 4vw, 48px);
}

.page-about .ab-org__copy .prose {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink);
}

.page-about .ab-org__link-line {
  margin: 22px 0 0;
}

.page-about .ab-inline-link {
  display: inline-block;
  font-size: 15px;
  font-weight: 700;
  color: var(--teal);
  text-decoration: none;
  border-bottom: 2px solid var(--teal);
  padding-bottom: 2px;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.page-about .ab-inline-link:hover,
.page-about .ab-inline-link:focus-visible {
  color: var(--red);
  border-bottom-color: var(--red);
}

.page-about .ab-inline-link:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

.page-about .ab-org__list {
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-org__card {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 4px 16px;
  align-items: start;
  padding: 16px 18px;
}

.page-about .ab-org__n {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--red);
  padding-top: 4px;
}

.page-about .ab-org__title {
  margin: 0 0 6px;
  font-size: 17px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--ink);
}

.page-about .ab-org__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 客服 ---------- */
.page-about .ab-support {
  background:
    linear-gradient(180deg, transparent 60%, rgba(216, 205, 185, 0.35)),
    var(--paper);
}

.page-about .ab-support__grid {
  display: grid;
  gap: clamp(26px, 4vw, 48px);
}

.page-about .ab-support__copy .prose {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink);
}

.page-about .ab-support__links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 26px;
  margin: 22px 0 0;
}

.page-about .ab-support__cards {
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-support__card {
  padding: 20px 20px 22px;
}

.page-about .ab-support__n {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(30px, 4.6vw, 46px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--cyan);
  margin-bottom: 10px;
}

.page-about .ab-support__card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: rgba(243, 236, 223, 0.82);
}

/* ---------- 版本记录 ---------- */
.page-about .ab-versions__lede {
  max-width: 40em;
  margin: 0;
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink);
}

.page-about .ab-versions__meta {
  display: grid;
  gap: 0;
  margin: clamp(26px, 4vw, 44px) 0 0;
  padding: 0;
  list-style: none;
  border-top: var(--bw) solid var(--ink);
}

.page-about .ab-versions__meta > li {
  display: grid;
  grid-template-columns: minmax(88px, 120px) minmax(0, 1fr);
  gap: 6px 20px;
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .ab-versions__k {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--night);
  padding-top: 3px;
}

.page-about .ab-versions__v {
  font-size: 15px;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 收尾入口 ---------- */
.page-about .ab-cta {
  padding: clamp(44px, 8vw, 96px) 0;
  background:
    linear-gradient(200deg, rgba(210, 49, 28, 0.22), transparent 48%),
    var(--night);
  color: var(--paper);
  border-top: var(--bw) solid var(--ink);
}

.page-about .ab-cta__title {
  margin: 0;
  font-size: clamp(24px, 3.8vw, 40px);
  line-height: 1.25;
  font-weight: 900;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .ab-cta__grid {
  display: grid;
  gap: 14px;
  margin-top: clamp(24px, 4vw, 40px);
}

.page-about .ab-cta__card {
  display: flex;
  flex-direction: column;
  gap: 7px;
  padding: 20px 18px 22px;
  background: var(--paper);
  color: var(--ink);
  text-decoration: none;
}

.page-about .ab-cta__card strong {
  font-size: 17px;
  font-weight: 700;
  color: var(--ink);
}

.page-about .ab-cta__card > span:last-child {
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .ab-cta__k {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--red);
}

.page-about .ab-cta__card:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .ab-cta__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 760px) {
  .page-about .ab-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 860px) {
  .page-about .ab-zones__grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
    align-items: center;
    gap: clamp(32px, 5vw, 64px);
  }
}

@media (min-width: 900px) {
  .page-about .ab-org__grid,
  .page-about .ab-support__grid {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
    align-items: start;
    gap: clamp(36px, 6vw, 72px);
  }

  .page-about .ab-revamp__inner {
    grid-template-columns: minmax(0, 0.82fr) minmax(0, 1.18fr);
    align-items: start;
    gap: clamp(32px, 6vw, 80px);
  }

  .page-about .ab-revamp__head {
    position: sticky;
    top: clamp(90px, 14vh, 132px);
    margin-bottom: 0;
  }
}

@media (min-width: 920px) {
  .page-about .ab-timeline__grid {
    grid-template-columns: minmax(150px, 190px) minmax(0, 1fr);
    gap: clamp(36px, 6vw, 88px);
    align-items: start;
  }

  .page-about .ab-index {
    position: sticky;
    top: clamp(90px, 14vh, 132px);
  }

  .page-about .ab-index__list {
    flex-direction: column;
    gap: 2px;
    padding: 0;
    overflow: visible;
    border-left: var(--bw) solid var(--ink);
  }

  .page-about .ab-index__link {
    width: 100%;
    padding: 11px 12px;
    margin-left: -3px;
    background: transparent;
    border: 0;
    border-left: 3px solid transparent;
    box-shadow: none;
  }

  .page-about .ab-index__link:hover,
  .page-about .ab-index__link:focus-visible {
    border-left-color: var(--red);
    color: var(--red);
    box-shadow: none;
    transform: none;
  }

  .page-about .ab-figure--narrow {
    width: 76%;
    margin-left: auto;
  }
}

@media (min-width: 1000px) {
  .page-about .ab-cta__grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .tl-node,
  .page-about .ab-index__link,
  .page-about .ab-inline-link {
    transition-duration: 0.01ms;
  }

  .page-about .tl-node:target {
    animation: none;
    border-color: var(--cyan);
    box-shadow: 8px 8px 0 var(--cyan);
  }

  .page-about .tl-node:hover {
    transform: none;
  }

  .page-about .ab-index__link:hover {
    transform: none;
  }
}
<<<END>>>