.page-about {
  --ab-line: rgba(110, 116, 122, .28);
  --ab-pad-y: clamp(56px, 9vw, 120px);
  --ab-tl-pad: 28px;
  background: var(--ink);
  color: var(--cream);
  overflow-x: clip;
}

.page-about .ab-p {
  margin: 0 0 20px;
  max-width: 40ch;
  font-size: 16px;
  line-height: 1.75;
  color: var(--mist);
}

.page-about .ab-h2 {
  margin: 12px 0 0;
  font-size: clamp(1.55rem, 5.4vw, 2.75rem);
  font-weight: 500;
  line-height: 1.14;
  letter-spacing: .015em;
  color: var(--cream);
}

.page-about .ab-section {
  position: relative;
  padding: var(--ab-pad-y) 0;
}

.page-about .label {
  color: var(--stone);
}

.page-about .ab-link {
  color: var(--neon);
  text-decoration: none;
  border-bottom: 1px solid rgba(255, 122, 26, .45);
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

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

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  position: relative;
  padding: clamp(64px, 11vw, 148px) 0 clamp(44px, 6vw, 84px);
  background:
    radial-gradient(120% 80% at 92% -12%, rgba(255, 122, 26, .22), transparent 58%),
    radial-gradient(90% 70% at 6% 108%, rgba(78, 107, 82, .22), transparent 60%),
    linear-gradient(180deg, var(--ink) 0%, var(--ink-2) 100%);
}

.page-about .ab-crumb {
  margin-bottom: clamp(32px, 5vw, 68px);
}

.page-about .ab-hero__grid {
  display: grid;
  gap: clamp(28px, 5vw, 52px);
}

.page-about .ab-hero__kicker {
  color: var(--neon);
}

.page-about .ab-hero__title {
  margin: 16px 0 0;
  color: var(--cream);
}

.page-about .ab-hero__lead {
  margin: 0;
  max-width: 42ch;
  color: var(--mist);
}

.page-about .ab-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px 14px;
  margin-top: 40px;
  padding-top: 26px;
  border-top: 1px solid var(--ab-line);
}

.page-about .ab-fact__num {
  display: block;
  font-size: clamp(1.7rem, 4.6vw, 2.5rem);
  line-height: 1;
  color: var(--neon);
}

.page-about .ab-fact__k {
  display: block;
  margin-top: 10px;
  font-size: 13px;
  letter-spacing: .08em;
  color: var(--cream);
}

.page-about .ab-fact__d {
  display: block;
  margin-top: 6px;
  font-size: 12px;
  line-height: 1.6;
  color: var(--stone);
}

/* ---------- 起点 ---------- */
.page-about .ab-origin {
  background: linear-gradient(180deg, var(--ink-2) 0%, var(--ink) 100%);
}

.page-about .ab-origin__grid {
  display: grid;
  gap: clamp(28px, 4vw, 48px);
}

.page-about .ab-origin__stamp {
  display: inline-block;
  margin-top: 28px;
  padding: 8px 16px;
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--clay);
  border: 1px solid rgba(180, 112, 90, .5);
  border-radius: var(--r-pill);
}

.page-about .ab-checks {
  list-style: none;
  margin: 32px 0 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .ab-checks__item {
  position: relative;
  padding-left: 26px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--cream);
}

.page-about .ab-checks__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 8px;
  width: 13px;
  height: 9px;
  background: var(--moss);
  clip-path: polygon(0 100%, 22% 0, 100% 0, 78% 100%);
}

/* ---------- 赛季结构 ---------- */
.page-about .ab-season {
  background: var(--panel);
}

.page-about .ab-season__lead {
  margin: 20px 0 0;
  max-width: 44ch;
  color: var(--mist);
}

.page-about .ab-stages {
  list-style: none;
  margin: clamp(32px, 5vw, 56px) 0 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .ab-stage {
  padding: 28px 24px 30px;
  background: rgba(10, 26, 47, .62);
  border-left: 3px solid var(--neon);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 16px), calc(100% - 16px) 100%, 0 100%);
  transition: background var(--dur) var(--ease);
}

.page-about .ab-stage:hover {
  background: rgba(10, 26, 47, .9);
}

.page-about .ab-stage__idx {
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--neon);
}

.page-about .ab-stage__title {
  margin: 14px 0 10px;
  font-size: 1.25rem;
  font-weight: 600;
  letter-spacing: .04em;
  color: var(--cream);
}

.page-about .ab-stage__text {
  margin: 0 0 18px;
  font-size: 15px;
  line-height: 1.72;
  color: var(--mist);
}

.page-about .ab-stage__meta {
  display: block;
  padding-top: 14px;
  border-top: 1px solid var(--ab-line);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--neon-soft);
}

.page-about .ab-levels {
  position: relative;
  margin-top: clamp(44px, 7vw, 88px);
}

.page-about .ab-levels__intro {
  margin: 0 0 24px;
  max-width: 40ch;
  font-size: 15px;
  line-height: 1.75;
  color: var(--mist);
}

.page-about .ab-radio {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: 0;
  padding: 0;
  opacity: 0;
  pointer-events: none;
}

.page-about .ab-levels__tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .ab-tab {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 24px;
  border-radius: var(--r-pill);
  border: 1px solid var(--ab-line);
  color: var(--mist);
  font-size: 14px;
  letter-spacing: .08em;
  cursor: pointer;
  transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.page-about .ab-tab:hover {
  border-color: var(--neon-soft);
  color: var(--cream);
}

.page-about #lv-open:checked ~ .ab-levels__tabs label[for="lv-open"],
.page-about #lv-adv:checked ~ .ab-levels__tabs label[for="lv-adv"],
.page-about #lv-elite:checked ~ .ab-levels__tabs label[for="lv-elite"] {
  background: var(--neon);
  border-color: var(--neon);
  color: var(--ink);
}

.page-about #lv-open:focus-visible ~ .ab-levels__tabs label[for="lv-open"],
.page-about #lv-adv:focus-visible ~ .ab-levels__tabs label[for="lv-adv"],
.page-about #lv-elite:focus-visible ~ .ab-levels__tabs label[for="lv-elite"] {
  box-shadow: 0 0 0 2px var(--panel), 0 0 0 4px var(--neon);
}

.page-about .ab-levels__panels {
  margin-top: 26px;
}

.page-about .ab-level {
  display: none;
  padding: 28px 24px;
  background: rgba(10, 26, 47, .62);
  border-top: 1px solid rgba(255, 122, 26, .45);
  border-radius: 0 0 var(--r-soft) var(--r-soft);
}

.page-about #lv-open:checked ~ .ab-levels__panels .ab-level[data-level="open"],
.page-about #lv-adv:checked ~ .ab-levels__panels .ab-level[data-level="adv"],
.page-about #lv-elite:checked ~ .ab-levels__panels .ab-level[data-level="elite"] {
  display: block;
}

.page-about .ab-level__name {
  margin: 0 0 20px;
  font-size: 1.2rem;
  font-weight: 600;
  letter-spacing: .06em;
  color: var(--neon);
}

.page-about .ab-level__grid {
  margin: 0;
  display: grid;
  gap: 20px;
}

.page-about .ab-level__cell dt {
  margin: 0 0 8px;
  color: var(--stone);
}

.page-about .ab-level__cell dd {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--cream);
}

/* ---------- 判罚 ---------- */
.page-about .ab-rules {
  background:
    radial-gradient(80% 60% at 100% 0%, rgba(228, 71, 43, .14), transparent 55%),
    radial-gradient(70% 60% at 0% 100%, rgba(242, 197, 61, .12), transparent 58%),
    var(--ink);
}

.page-about .ab-rules__grid {
  display: grid;
  gap: clamp(32px, 5vw, 56px);
}

.page-about .ab-rules__media .figure {
  background: rgba(19, 42, 74, .5);
  border: 1px solid var(--ab-line);
}

.page-about .ab-cards {
  display: grid;
  gap: 16px;
  margin-top: 32px;
}

.page-about .ab-card {
  position: relative;
  overflow: hidden;
  min-height: 232px;
  padding: 26px 22px 30px;
  background: var(--ink-2);
  border: 1px solid var(--ab-line);
  border-radius: var(--r-soft);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .ab-card:hover,
.page-about .ab-card:focus-visible {
  border-color: var(--neon);
  transform: translateY(-3px);
  outline: none;
}

.page-about .ab-card:focus-visible {
  box-shadow: 0 0 0 2px var(--ink), 0 0 0 4px var(--neon);
}

.page-about .ab-card__sym {
  display: block;
  width: 36px;
  height: 26px;
  margin-bottom: 18px;
  clip-path: polygon(0 100%, 22% 0, 100% 0, 78% 100%);
}

.page-about .ab-card--info .ab-card__sym { background: var(--mist); }
.page-about .ab-card--warn .ab-card__sym { background: var(--yellow); }
.page-about .ab-card--red .ab-card__sym { background: var(--red); }

.page-about .ab-card__title {
  margin: 0 0 10px;
  font-size: 1.15rem;
  font-weight: 600;
  letter-spacing: .06em;
  color: var(--cream);
}

.page-about .ab-card__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--mist);
}

.page-about .ab-card__slip {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 18px 22px;
  background: var(--panel);
  border-top: 1px solid var(--ab-line);
  transform: translateY(105%);
  transition: transform 220ms var(--ease);
}

.page-about .ab-card--warn .ab-card__slip { border-top-color: rgba(242, 197, 61, .7); }
.page-about .ab-card--red .ab-card__slip { border-top-color: rgba(228, 71, 43, .7); }

.page-about .ab-card:hover .ab-card__slip,
.page-about .ab-card:focus-within .ab-card__slip {
  transform: translateY(0);
}

.page-about .ab-card__slip-k {
  color: var(--stone);
}

.page-about .ab-card__slip-v {
  margin: 6px 0 0;
  font-size: 14px;
  line-height: 1.6;
  color: var(--cream);
}

.page-about .ab-rules__note {
  margin: 28px 0 0;
  max-width: 42ch;
  font-size: 14px;
  line-height: 1.75;
  color: var(--stone);
}

/* ---------- 团队 ---------- */
.page-about .ab-team {
  background: var(--cream);
  color: var(--ink);
}

.page-about .ab-team .label { color: var(--clay); }
.page-about .ab-team .ab-h2 { color: var(--ink); }

.page-about .ab-team__lead {
  margin: 20px 0 0;
  max-width: 42ch;
  color: #4A5259;
}

.page-about .ab-team__grid {
  margin-top: clamp(32px, 5vw, 52px);
  display: grid;
  gap: clamp(28px, 4vw, 48px);
}

.page-about .ab-team__figure {
  background: rgba(10, 26, 47, .08);
}

.page-about .ab-team__figure .figure__caption {
  color: var(--stone);
}

.page-about .ab-team__cols {
  display: grid;
  gap: 24px;
}

.page-about .ab-team__col {
  padding-top: 20px;
  border-top: 2px solid var(--ink);
}

.page-about .ab-team__num {
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--clay);
}

.page-about .ab-team__name {
  margin: 12px 0 10px;
  font-size: 1.15rem;
  font-weight: 600;
  letter-spacing: .05em;
  color: var(--ink);
}

.page-about .ab-team__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
  color: #4A5259;
}

/* ---------- 里程碑 ---------- */
.page-about .ab-mile {
  position: relative;
  overflow: hidden;
  background: var(--ink-2);
}

.page-about .ab-mile__bg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: .18;
}

.page-about .ab-mile__inner {
  position: relative;
  z-index: 1;
}

.page-about .ab-mile__lead {
  margin: 20px 0 0;
  max-width: 42ch;
  color: var(--mist);
}

.page-about .ab-mile__grid {
  display: grid;
  gap: clamp(28px, 4vw, 52px);
  margin-top: clamp(32px, 5vw, 56px);
}

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

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

.page-about .ab-idx__link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 40px;
  padding: 0 14px;
  border-radius: var(--r-pill);
  border: 1px solid var(--ab-line);
  font-size: 13px;
  color: var(--mist);
  text-decoration: none;
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .ab-idx__link:hover {
  border-color: var(--neon);
  color: var(--cream);
  background: rgba(255, 122, 26, .1);
}

.page-about .ab-timeline {
  position: relative;
  padding-left: var(--ab-tl-pad);
}

.page-about .ab-timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(180deg, var(--neon) 0%, rgba(255, 122, 26, .12) 100%);
}

.page-about .ms {
  position: relative;
  padding-bottom: 8px;
  scroll-margin-top: 96px;
}

.page-about .ms__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 14px;
  min-height: 44px;
  padding: 12px 0;
  cursor: pointer;
  list-style: none;
}

.page-about .ms__head::-webkit-details-marker { display: none; }

.page-about .ms__dot {
  position: absolute;
  left: calc(1px - var(--ab-tl-pad));
  top: 18px;
  width: 14px;
  height: 14px;
  background: var(--stone);
  clip-path: polygon(0 100%, 25% 0, 100% 0, 75% 100%);
  transition: background var(--dur) var(--ease);
}

.page-about .ms[open] .ms__dot,
.page-about .ms__head:hover .ms__dot {
  background: var(--neon);
}

.page-about .ms__idx {
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--neon);
}

.page-about .ms__title {
  font-size: clamp(1rem, 2.6vw, 1.2rem);
  font-weight: 500;
  letter-spacing: .02em;
  color: var(--cream);
  transition: color var(--dur) var(--ease);
}

.page-about .ms__head:hover .ms__title {
  color: var(--neon-soft);
}

.page-about .ms__note {
  margin: 0 0 18px;
  max-width: 48ch;
  font-size: 15px;
  line-height: 1.75;
  color: var(--mist);
}

/* ---------- 合作生态 ---------- */
.page-about .ab-partners {
  background: var(--clay);
  color: var(--ink);
}

.page-about .ab-partners .label--dark { color: rgba(10, 26, 47, .66); }
.page-about .ab-partners .ab-h2 { color: var(--ink); }

.page-about .ab-partners__lead {
  margin: 20px 0 0;
  max-width: 44ch;
  color: #33201A;
}

.page-about .ab-partners__list {
  list-style: none;
  margin: clamp(32px, 5vw, 52px) 0 0;
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .ab-partners__item {
  padding: 24px 0;
  border-top: 1px solid rgba(10, 26, 47, .28);
}

.page-about .ab-partners__item:last-child {
  border-bottom: 1px solid rgba(10, 26, 47, .28);
}

.page-about .ab-partners__name {
  margin: 0 0 8px;
  font-size: 1.15rem;
  font-weight: 600;
  letter-spacing: .05em;
  color: var(--ink);
}

.page-about .ab-partners__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: #33201A;
}

.page-about .ab-partners__note {
  margin: 30px 0 0;
  max-width: 46ch;
  font-size: 15px;
  line-height: 1.75;
  color: #33201A;
}

.page-about .ab-link--dark {
  color: var(--ink);
  border-bottom-color: rgba(10, 26, 47, .5);
}

.page-about .ab-link--dark:hover {
  color: #33201A;
  border-bottom-color: var(--ink);
}

/* ---------- 行动区 ---------- */
.page-about .ab-next {
  padding: var(--ab-pad-y) 0 clamp(72px, 10vw, 140px);
  background: linear-gradient(180deg, var(--ink) 0%, var(--ink-2) 100%);
}

.page-about .ab-next__list {
  list-style: none;
  margin: clamp(28px, 4vw, 44px) 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .ab-next__link {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 8px 20px;
  min-height: 64px;
  padding: 18px 26px;
  border: 1px solid var(--ab-line);
  border-radius: var(--r-pill);
  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(--neon);
  background: rgba(255, 122, 26, .08);
  transform: translateX(4px);
}

.page-about .ab-next__k {
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--neon);
  text-transform: uppercase;
}

.page-about .ab-next__v {
  font-size: 15px;
  color: var(--cream);
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .ab-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 24px 20px;
  }

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

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

  .page-about .ab-partners__list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 0 32px;
  }

  .page-about .ab-next__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
  }
}

@media (min-width: 900px) {
  .page-about .ab-hero__grid {
    grid-template-columns: 7fr 5fr;
    align-items: end;
    gap: clamp(40px, 5vw, 88px);
  }

  .page-about .ab-origin__grid {
    grid-template-columns: 3fr 7fr;
    gap: clamp(48px, 7vw, 128px);
  }

  .page-about .ab-stages {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 20px;
  }

  .page-about .ab-level {
    padding: 36px 40px;
  }

  .page-about .ab-rules__grid {
    grid-template-columns: 4fr 7fr;
    gap: clamp(48px, 6vw, 96px);
    align-items: start;
  }

  .page-about .ab-team__cols {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 32px;
  }
}

@media (min-width: 960px) {
  .page-about {
    --ab-tl-pad: 40px;
  }

  .page-about .ab-mile__grid {
    grid-template-columns: 1fr 2.2fr;
    gap: clamp(48px, 7vw, 140px);
  }

  .page-about .ab-idx {
    position: sticky;
    top: 40px;
    align-self: start;
  }

  .page-about .ab-idx__list {
    flex-direction: column;
    gap: 0;
  }

  .page-about .ab-idx__link {
    display: flex;
    min-height: 44px;
    padding: 0 0 0 20px;
    border: 0;
    border-left: 2px solid var(--ab-line);
    border-radius: 0;
    background: none;
    font-size: 13px;
    letter-spacing: .04em;
  }

  .page-about .ab-idx__link:hover {
    border-left-color: var(--neon);
    background: none;
  }

  .page-about .ms {
    padding-bottom: 14px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-card,
  .page-about .ab-card__slip,
  .page-about .ab-stage,
  .page-about .ab-next__link,
  .page-about .ab-idx__link,
  .page-about .ab-link,
  .page-about .ms__dot,
  .page-about .ms__title {
    transition: none;
  }

  .page-about .ab-card:hover,
  .page-about .ab-next__link:hover {
    transform: none;
  }
}