.page-about {
  background: var(--ink);
  color: var(--mist);
  overflow-x: clip;
}

.page-about .breadcrumbs {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--sage);
  margin-bottom: clamp(22px, 4vw, 40px);
}

.page-about .breadcrumbs a {
  color: var(--sage);
  text-decoration: none;
}

.page-about .breadcrumbs a:hover {
  color: var(--lime);
}

/* ---------- 开篇 ---------- */

.page-about .ab-hero {
  position: relative;
  padding: clamp(34px, 7vw, 78px) 0 clamp(38px, 6vw, 76px);
  isolation: isolate;
}

.page-about .ab-hero::before {
  content: "";
  position: absolute;
  inset: -14% -12% auto auto;
  width: min(620px, 78vw);
  height: min(620px, 78vw);
  background:
    radial-gradient(circle at 62% 38%, rgba(198, 242, 78, .17), transparent 62%),
    linear-gradient(140deg, rgba(18, 48, 41, .95), rgba(17, 20, 19, .1));
  clip-path: polygon(20% 0, 100% 14%, 84% 100%, 0 78%);
  z-index: -1;
}

.page-about .ab-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 5vw, 56px);
}

.page-about .ab-hero__text h1 {
  margin: 0 0 20px;
  font-family: var(--font-display);
  font-size: clamp(32px, 8.4vw, 68px);
  line-height: 1.04;
  letter-spacing: -.012em;
  color: var(--mist);
  max-width: 15em;
}

.page-about .ab-hero__text .lead {
  margin: 0;
  max-width: 40em;
  font-size: clamp(15px, 2.4vw, 18px);
  line-height: 1.85;
  color: var(--mist);
}

.page-about .ab-hero__figures {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: clamp(26px, 5vw, 42px);
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  overflow: hidden;
}

.page-about .ab-fig {
  background: linear-gradient(180deg, rgba(27, 59, 51, .78), rgba(10, 28, 24, .94));
  padding: 16px 14px 18px;
}

.page-about .ab-fig__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(26px, 7vw, 38px);
  line-height: 1;
  color: var(--lime);
}

.page-about .ab-fig__unit {
  font-size: .42em;
  color: var(--sage);
  margin-left: 3px;
  letter-spacing: .04em;
}

.page-about .ab-fig__label {
  display: block;
  margin-top: 9px;
  font-size: 13px;
  color: var(--sage);
  line-height: 1.5;
}

.page-about .ab-hero__plaque {
  margin: 0;
  align-self: start;
  border-radius: var(--r-lg);
}

.page-about .ab-hero__plaque .media-frame__img {
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-about .media-frame__caption {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--sage);
}

/* ---------- 展签 ---------- */

.page-about .ab-ledger {
  background: var(--char);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-about .ab-ledger__head {
  margin-bottom: clamp(20px, 4vw, 34px);
}

.page-about .ab-ledger__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin: 0;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  overflow: hidden;
}

.page-about .ab-ledger__item {
  background: rgba(10, 28, 24, .86);
  padding: 20px 18px 22px;
}

.page-about .ab-ledger__item dt {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--gold);
  margin-bottom: 10px;
}

.page-about .ab-ledger__item dd {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--mist);
}

/* ---------- 时间轴 ---------- */

.page-about .ab-growth__intro,
.page-about .ab-squad__intro,
.page-about .ab-flow__intro,
.page-about .ab-build__intro {
  margin-top: 14px;
  max-width: 46em;
  font-size: 16px;
  line-height: 1.85;
  color: var(--mist);
}

.page-about .ab-growth__band {
  margin: 0 0 clamp(24px, 4vw, 40px);
  border-radius: var(--r-lg);
}

.page-about .ab-growth__band .media-frame__img {
  width: 100%;
  height: auto;
  aspect-ratio: 8 / 3;
  object-fit: cover;
}

.page-about .ab-rail {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .ab-rail::before {
  content: "";
  position: absolute;
  left: 11px;
  top: 10px;
  bottom: 10px;
  width: 2px;
  background: linear-gradient(180deg, var(--gold), rgba(227, 176, 75, .12));
}

.page-about .ab-rail__item {
  position: relative;
  padding: 0 0 clamp(20px, 3vw, 30px) 42px;
}

.page-about .ab-rail__dot {
  position: absolute;
  left: 4px;
  top: 8px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  border: 2px solid var(--gold);
  background: var(--ink);
  z-index: 1;
}

.page-about .ab-rail__item.is-active .ab-rail__dot,
.page-about .ab-rail__item[data-open] .ab-rail__dot {
  border-color: var(--lime);
  background: var(--lime);
  box-shadow: 0 0 0 5px rgba(198, 242, 78, .14);
}

.page-about .ab-rail .collapse__head {
  display: block;
  width: 100%;
  padding: 0;
  border: 0;
  background: none;
  color: inherit;
  font: inherit;
  text-align: left;
  cursor: pointer;
}

.page-about .ab-rail__tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--gold);
  margin-bottom: 8px;
}

.page-about .ab-rail__name {
  display: block;
  font-family: var(--font-display);
  font-size: clamp(19px, 3.6vw, 28px);
  line-height: 1.28;
  color: var(--mist);
}

.page-about .ab-rail__sum {
  display: block;
  margin-top: 8px;
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--lime);
  line-height: 1.5;
}

.page-about .ab-rail .collapse__body p {
  margin: 12px 0 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--sage);
  max-width: 48em;
}

/* ---------- 团队 ---------- */

.page-about .ab-squad {
  background: var(--deep);
  border-top: 1px solid var(--line);
}

.page-about .ab-squad .filter-bar {
  margin: clamp(20px, 4vw, 30px) 0 clamp(18px, 3vw, 26px);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  background: var(--glass-bg);
}

.page-about .ab-squad .filter-bar__label {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--sage);
  margin-right: 6px;
}

.page-about .ab-squad .tag {
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: 13px;
  padding: 6px 13px;
  border-radius: 999px;
  border: 1px solid var(--line-strong);
  background: transparent;
  color: var(--mist);
}

.page-about .ab-squad .tag.is-active {
  background: var(--lime);
  border-color: var(--lime);
  color: var(--ink);
}

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

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

.page-about .ab-squad {
  overflow: hidden;
}

.page-about .ab-squads .ab-squad {
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  background: linear-gradient(158deg, rgba(27, 59, 51, .82), rgba(10, 28, 24, .92));
  padding: 18px 18px 20px;
}

.page-about .ab-squads .ab-squad::after {
  content: "";
  position: absolute;
  right: -34px;
  top: -34px;
  width: 118px;
  height: 118px;
  background: radial-gradient(circle, rgba(198, 242, 78, .16), transparent 70%);
  pointer-events: none;
}

.page-about .ab-squad__code {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--gold);
}

.page-about .ab-squad__name {
  margin: 8px 0 10px;
  font-size: 19px;
  line-height: 1.35;
  color: var(--mist);
}

.page-about .ab-squads .ab-squad p {
  margin: 0 0 10px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--sage);
}

.page-about .ab-squad__meta {
  font-family: var(--font-mono);
  font-size: 12px !important;
  letter-spacing: .05em;
  color: var(--lime) !important;
  padding-top: 10px;
  border-top: 1px solid var(--line);
}

.page-about .ab-squad__figure {
  margin: clamp(26px, 5vw, 44px) 0 0;
  max-width: 520px;
  border-radius: var(--r-lg);
}

.page-about .ab-squad__figure .media-frame__img {
  width: 100%;
  height: auto;
  aspect-ratio: 1 / 1;
  object-fit: cover;
}

/* ---------- 流程 ---------- */

.page-about .ab-flow {
  background: var(--char);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-about .ab-flow__steps {
  list-style: none;
  margin: clamp(22px, 4vw, 34px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .ab-step {
  position: relative;
  border-radius: var(--r-md);
  border: 1px solid var(--line);
  border-left: 3px solid var(--gold);
  background: rgba(10, 28, 24, .82);
  padding: 20px 18px 22px;
}

.page-about .ab-step__no {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--sage);
}

.page-about .ab-step__name {
  margin: 10px 0 12px;
  font-size: 18px;
  color: var(--mist);
}

.page-about .ab-step__numline {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: clamp(30px, 6vw, 42px);
  line-height: 1;
  color: var(--lime);
}

.page-about .ab-step__numline span {
  font-size: .35em;
  color: var(--sage);
  letter-spacing: .06em;
  margin-left: 4px;
}

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

.page-about .ab-flow__plate {
  margin-top: clamp(20px, 4vw, 30px);
}

/* ---------- 覆盖范围 ---------- */

.page-about .ab-cover__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 44px);
  margin-top: clamp(20px, 4vw, 32px);
}

.page-about .ab-cover__num {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: clamp(24px, 5vw, 36px);
  line-height: 1.15;
  color: var(--mist);
}

.page-about .ab-cover__num .num {
  font-family: var(--font-mono);
  font-size: 1.5em;
  color: var(--lime);
  margin-right: 6px;
}

.page-about .ab-cover__note {
  margin: 0 0 18px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--sage);
  max-width: 30em;
}

.page-about .ab-prov {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(22px, 1fr));
  gap: 5px;
  max-width: 400px;
}

.page-about .ab-prov__cell {
  display: block;
  aspect-ratio: 1 / 1;
  border-radius: 3px;
  background: linear-gradient(160deg, var(--lime), rgba(198, 242, 78, .3));
  box-shadow: inset 0 0 0 1px rgba(10, 28, 24, .35);
}

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

.page-about .ab-audience__item {
  background: rgba(10, 28, 24, .88);
  padding: 18px 18px 20px;
}

.page-about .ab-audience__name {
  margin: 0 0 8px;
  font-size: 16px;
  color: var(--mist);
}

.page-about .ab-audience__item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--sage);
}

/* ---------- 版本 ---------- */

.page-about .ab-version {
  background: var(--deep);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-about .ab-versions {
  list-style: none;
  margin: clamp(22px, 4vw, 34px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-about .ab-ver {
  position: relative;
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  padding: 18px 18px 20px;
  background: linear-gradient(200deg, rgba(18, 48, 41, .9), rgba(10, 28, 24, .78));
}

.page-about .ab-ver__tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 15px;
  letter-spacing: .1em;
  color: var(--ink);
  background: var(--gold);
  border-radius: var(--r-sm);
  padding: 3px 9px;
}

.page-about .ab-ver__name {
  margin: 12px 0 10px;
  font-size: 17px;
  color: var(--mist);
}

.page-about .ab-ver p {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--sage);
}

.page-about .ab-version__plate {
  margin-top: clamp(20px, 4vw, 30px);
}

/* ---------- 共建 ---------- */

.page-about .ab-build__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin-top: clamp(22px, 4vw, 34px);
}

.page-about .ab-build__card {
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  padding: 20px 18px 22px;
  background: rgba(17, 20, 19, .72);
}

.page-about .ab-build__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(30px, 6vw, 44px);
  line-height: 1;
  color: var(--brick);
}

.page-about .ab-build__card h3 {
  margin: 12px 0 10px;
  font-size: 17px;
  color: var(--mist);
}

.page-about .ab-build__card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--sage);
}

/* ---------- 收束 ---------- */

.page-about .ab-next {
  padding-bottom: clamp(48px, 8vw, 96px);
}

.page-about .ab-next__panel {
  position: relative;
  border: 1px solid var(--line-strong);
  border-radius: var(--r-lg);
  padding: clamp(24px, 5vw, 48px);
  background:
    linear-gradient(120deg, rgba(27, 59, 51, .55), rgba(10, 28, 24, .5)),
    repeating-linear-gradient(90deg, rgba(227, 176, 75, .07) 0 2px, transparent 2px 74px);
}

.page-about .ab-next__text {
  margin: 16px 0 0;
  max-width: 44em;
  font-size: 15px;
  line-height: 1.85;
  color: var(--sage);
}

.page-about .ab-next__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: clamp(22px, 4vw, 32px);
}

.page-about .ab-next__actions .btn {
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
}

/* ---------- 响应式 ---------- */

@media (min-width: 641px) {
  .page-about .ab-hero__figures {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

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

@media (min-width: 901px) {
  .page-about .ab-hero__grid {
    grid-template-columns: minmax(0, 1.18fr) minmax(0, .82fr);
    align-items: start;
  }

  .page-about .ab-rail__item {
    padding-left: 56px;
  }

  .page-about .ab-rail .collapse__head {
    display: grid;
    grid-template-columns: 64px minmax(0, 1fr) 220px;
    align-items: baseline;
    gap: 18px;
  }

  .page-about .ab-rail__tag {
    margin-bottom: 0;
  }

  .page-about .ab-rail__sum {
    margin-top: 0;
    text-align: right;
  }

  .page-about .ab-rail .collapse__body p {
    margin-left: 82px;
  }

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

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

  .page-about .ab-versions {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .ab-cover__grid {
    grid-template-columns: minmax(0, .85fr) minmax(0, 1.15fr);
    align-items: start;
  }

  .page-about .ab-build__grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .ab-squad__figure {
    max-width: 620px;
  }
}

@media (min-width: 1201px) {
  .page-about .ab-hero__text h1 {
    letter-spacing: -.018em;
  }
}