.page-about {
  background:
    radial-gradient(1100px 480px at 78% -12%, rgba(63, 227, 210, .10), transparent 68%),
    var(--ink-950);
  color: var(--text-hi);
  overflow-x: clip;
}

.page-about .ab-crumb {
  padding-top: 18px;
}

.page-about .ab-crumb .breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: .78rem;
  color: var(--mist-300);
}

.page-about .ab-crumb .breadcrumb__link {
  color: var(--mist-300);
  text-decoration: none;
}

.page-about .ab-crumb .breadcrumb__link:hover,
.page-about .ab-crumb .breadcrumb__link:focus-visible {
  color: var(--cyan-400);
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  padding: clamp(24px, 5vw, 60px) 0 clamp(34px, 6vw, 76px);
}

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

.page-about .ab-hero h1 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.95rem, 6.2vw, 3.5rem);
  line-height: 1.14;
  letter-spacing: -0.01em;
  margin: 14px 0 18px;
  max-width: 15em;
}

.page-about .ab-hero__text {
  max-width: 34em;
  margin: 0 0 14px;
  color: var(--text-mid);
  font-size: 1rem;
  line-height: 1.8;
}

.page-about .ab-hero__lead .btn {
  margin-top: 10px;
}

.page-about .ab-panel {
  position: relative;
  padding: 22px 22px 16px 30px;
  border-radius: var(--radius-lg);
  background: linear-gradient(180deg, var(--ink-800), var(--ink-900));
  box-shadow: var(--shadow-panel);
}

.page-about .ab-panel::before {
  content: "";
  position: absolute;
  left: 16px;
  top: 30px;
  bottom: 30px;
  width: 2px;
  border-radius: 2px;
  background: repeating-linear-gradient(180deg, var(--cyan-400) 0 7px, transparent 7px 17px);
}

.page-about .ab-panel__label {
  margin: 0;
  font-size: .7rem;
  letter-spacing: .22em;
  color: var(--mist-300);
  text-transform: uppercase;
}

.page-about .ab-facts {
  list-style: none;
  margin: 12px 0 0;
  padding: 0;
}

.page-about .ab-fact {
  display: grid;
  grid-template-columns: 84px minmax(0, 1fr);
  gap: 12px;
  align-items: baseline;
  padding: 12px 0;
  border-top: 1px solid var(--ink-700);
}

.page-about .ab-fact:first-child {
  border-top: 0;
}

.page-about .ab-fact__num {
  font-size: 1.3rem;
  letter-spacing: -0.01em;
  color: var(--cyan-400);
}

.page-about .ab-fact__label {
  font-size: .82rem;
  line-height: 1.65;
  color: var(--mist-300);
}

/* ---------- 通用段落底座 ---------- */
.page-about .ab-band {
  padding: clamp(42px, 7vw, 88px) 0;
}

.page-about .ab-band__head {
  max-width: 40em;
  margin-bottom: clamp(24px, 4vw, 40px);
}

.page-about .ab-band__head--tight {
  margin-top: clamp(26px, 4vw, 44px);
}

.page-about .ab-band h2,
.page-about .ab-close h2 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.45rem, 3.6vw, 2.2rem);
  line-height: 1.24;
  letter-spacing: -0.01em;
  margin: 10px 0 0;
}

.page-about .ab-band__lede {
  margin: 12px 0 0;
  color: var(--mist-300);
  font-size: .92rem;
  line-height: 1.8;
}

/* ---------- 时间刻度 ---------- */
.page-about .ab-timeline {
  display: grid;
  gap: 22px;
}

.page-about .ab-ticks {
  display: flex;
  gap: 8px;
  list-style: none;
  margin: 0;
  padding: 0 0 6px;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .ab-tick {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 7px 13px;
  border-radius: var(--pill);
  background: var(--ink-800);
  color: var(--mist-300);
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .04em;
  text-decoration: none;
  white-space: nowrap;
  transition: background-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.page-about .ab-tick:hover,
.page-about .ab-tick:focus-visible {
  background: var(--ink-700);
  color: var(--cyan-400);
}

.page-about .ab-tick__dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--amber-400);
}

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

.page-about .ab-stage {
  scroll-margin-top: 96px;
  padding: 20px 22px;
  border-radius: var(--radius-md);
  border-left: 2px solid var(--ink-700);
  background: var(--ink-900);
  transition: background-color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .ab-stage:hover,
.page-about .ab-stage:focus-within {
  background: var(--ink-800);
  border-left-color: var(--cyan-400);
}

.page-about .ab-stage__year {
  margin: 0;
  font-size: .7rem;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--amber-400);
}

.page-about .ab-stage h3 {
  margin: 8px 0 8px;
  font-size: 1.08rem;
  font-weight: 700;
  line-height: 1.4;
}

.page-about .ab-stage p {
  margin: 0;
  color: var(--text-mid);
  font-size: .93rem;
  line-height: 1.78;
}

/* ---------- 图片框 ---------- */
.page-about .img-frame {
  overflow: hidden;
  border-radius: var(--radius-md);
  background: var(--ink-800);
}

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

.page-about .ab-figure {
  margin: clamp(24px, 4vw, 40px) 0 0;
  aspect-ratio: 3 / 2;
}

.page-about .ab-figure--wide {
  aspect-ratio: 14 / 9;
  margin-top: 0;
}

/* ---------- 纸面：内容体系 ---------- */
.page-about .ab-band--paper {
  background: linear-gradient(180deg, var(--ink-950), var(--ink-900));
}

.page-about .ab-sheet {
  background: var(--paper-050);
  color: var(--paper-ink);
  border-radius: var(--radius-lg);
  padding: clamp(24px, 5vw, 54px);
}

.page-about .ab-sheet .eyebrow {
  color: var(--paper-link);
}

.page-about .ab-sheet .eyebrow::before {
  background: var(--teal-600);
}

.page-about .ab-sheet h2 {
  color: var(--paper-ink);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.4rem, 3.4vw, 2rem);
  line-height: 1.28;
  margin: 10px 0 clamp(20px, 3vw, 32px);
  max-width: 22em;
}

.page-about .ab-sheet__grid {
  display: grid;
  gap: 26px;
}

.page-about .ab-sheet__col p {
  margin: 0 0 14px;
  font-size: .95rem;
  line-height: 1.85;
  color: #33434f;
}

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

.page-about .ab-metrics {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid rgba(27, 42, 54, .2);
}

.page-about .ab-metric {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 13px 0;
  border-bottom: 1px solid rgba(27, 42, 54, .2);
}

.page-about .ab-metric__num {
  min-width: 2.6em;
  font-size: 1.12rem;
  color: var(--paper-link);
  letter-spacing: -0.01em;
}

.page-about .ab-metric__label {
  font-size: .85rem;
  line-height: 1.6;
  color: #3b4a56;
}

/* ---------- 流程 ---------- */
.page-about .ab-flow {
  display: grid;
  gap: 12px;
  position: relative;
}

.page-about .ab-step {
  position: relative;
  padding: 18px 18px 16px;
  border-radius: var(--radius-md);
  border: 1px solid var(--ink-700);
  background: var(--ink-900);
  transition: background-color var(--dur) var(--ease), border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .ab-step:hover,
.page-about .ab-step:focus-within {
  background: var(--ink-800);
  border-color: var(--teal-600);
  transform: translateY(-3px);
}

.page-about .ab-step__index {
  display: inline-block;
  padding: 2px 10px;
  border-radius: var(--pill);
  background: var(--cyan-400);
  color: var(--ink-950);
  font-size: .7rem;
  letter-spacing: .06em;
}

.page-about .ab-step__name {
  margin: 12px 0 8px;
  font-size: 1.02rem;
  font-weight: 700;
}

.page-about .ab-step__text {
  margin: 0;
  font-size: .88rem;
  line-height: 1.75;
  color: var(--text-mid);
}

.page-about .ab-step__note {
  margin: 12px 0 0;
  padding-top: 10px;
  border-top: 1px dashed var(--ink-700);
  font-size: .78rem;
  line-height: 1.6;
  color: var(--mist-300);
}

/* ---------- 团队 ---------- */
.page-about .ab-team__bar {
  display: flex;
  gap: 3px;
  height: 12px;
  margin-bottom: 24px;
  border-radius: var(--pill);
  overflow: hidden;
}

.page-about .ab-seg {
  display: block;
  height: 100%;
  border-radius: var(--pill);
}

.page-about .ab-seg--edit {
  flex: 9 1 0;
  background: var(--cyan-400);
}

.page-about .ab-seg--video {
  flex: 4 1 0;
  background: var(--teal-600);
}

.page-about .ab-seg--data {
  flex: 3 1 0;
  background: var(--amber-400);
}

.page-about .ab-roles {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .ab-role {
  padding-top: 14px;
  border-top: 1px solid var(--ink-700);
}

.page-about .ab-role__head {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin: 0;
}

.page-about .ab-role__name {
  font-size: .98rem;
  font-weight: 700;
}

.page-about .ab-role__count {
  font-size: .78rem;
  color: var(--cyan-400);
}

.page-about .ab-role p {
  margin: 8px 0 0;
  font-size: .86rem;
  line-height: 1.75;
  color: var(--mist-300);
}

/* ---------- 结果 ---------- */
.page-about .ab-results__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .ab-result {
  padding: 22px;
  border-radius: var(--radius-md);
  background: linear-gradient(160deg, var(--ink-800), var(--ink-900));
  border: 1px solid var(--ink-700);
}

.page-about .ab-result__num {
  display: block;
  font-size: clamp(1.9rem, 5vw, 2.5rem);
  letter-spacing: -0.02em;
  color: var(--text-hi);
  line-height: 1.1;
}

.page-about .ab-result__unit {
  margin-left: 4px;
  font-family: var(--font-body);
  font-size: .86rem;
  color: var(--cyan-400);
}

.page-about .ab-result p {
  margin: 12px 0 0;
  font-size: .88rem;
  line-height: 1.75;
  color: var(--mist-300);
}

/* ---------- 收束 ---------- */
.page-about .ab-close {
  position: relative;
  overflow: hidden;
  margin-top: clamp(38px, 7vw, 84px);
  padding: clamp(52px, 9vw, 120px) 0 clamp(44px, 7vw, 84px);
}

.page-about .ab-close__bg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  max-width: 100%;
  object-fit: cover;
  opacity: .3;
}

.page-about .ab-close::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(6, 19, 32, .9), rgba(6, 19, 32, .7) 46%, var(--ink-950));
}

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

.page-about .ab-close__body {
  max-width: 44em;
}

.page-about .ab-close__text {
  margin: 14px 0 0;
  color: var(--text-mid);
  font-size: .95rem;
  line-height: 1.8;
}

.page-about .ab-cadence {
  list-style: none;
  margin: clamp(22px, 4vw, 34px) 0 0;
  padding: 0;
  border-top: 1px solid var(--ink-700);
}

.page-about .ab-cadence li {
  display: grid;
  gap: 4px;
  padding: 13px 0;
  border-bottom: 1px solid var(--ink-700);
}

.page-about .ab-cadence__k {
  font-size: .76rem;
  letter-spacing: .1em;
  color: var(--amber-400);
}

.page-about .ab-cadence__v {
  font-size: .9rem;
  line-height: 1.7;
  color: var(--text-mid);
}

.page-about .ab-close__actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px;
  margin-top: clamp(22px, 4vw, 32px);
}

.page-about .ab-link {
  color: var(--cyan-400);
  text-decoration: underline;
  text-underline-offset: 4px;
  text-decoration-thickness: 1px;
  transition: color var(--dur) var(--ease);
}

.page-about .ab-link:hover,
.page-about .ab-link:focus-visible {
  color: var(--cyan-300);
}

.page-about .ab-close__note {
  margin: 20px 0 0;
  font-size: .84rem;
  line-height: 1.85;
  color: var(--mist-300);
}

/* ---------- 响应式 ---------- */
@media (min-width: 760px) {
  .page-about .ab-flow {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 14px;
  }

  .page-about .ab-flow::before {
    content: "";
    position: absolute;
    top: 32px;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, var(--ink-700), var(--teal-600), var(--ink-700));
    z-index: 0;
  }

  .page-about .ab-step {
    z-index: 1;
  }

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

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

  .page-about .ab-cadence li {
    grid-template-columns: 8.5em minmax(0, 1fr);
    align-items: baseline;
    gap: 18px;
  }

  .page-about .ab-sheet__grid {
    grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr);
    gap: 44px;
  }

  .page-about .ab-timeline {
    grid-template-columns: 96px minmax(0, 1fr);
    gap: 40px;
  }

  .page-about .ab-ticks {
    position: sticky;
    top: 96px;
    align-self: start;
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding: 0 0 0 14px;
    border-left: 1px solid var(--ink-700);
  }

  .page-about .ab-tick {
    background: none;
    padding: 11px 0;
    border-radius: 0;
    font-size: .7rem;
    letter-spacing: .12em;
  }

  .page-about .ab-tick:hover,
  .page-about .ab-tick:focus-visible {
    background: none;
  }

  .page-about .ab-stages {
    gap: 18px;
  }

  .page-about .ab-stage {
    padding: 24px 28px;
  }
}

@media (min-width: 980px) {
  .page-about .ab-hero__grid {
    grid-template-columns: minmax(0, 1.45fr) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .ab-panel {
    margin-top: 8px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-step,
  .page-about .ab-step:hover,
  .page-about .ab-step:focus-within {
    transform: none;
  }

  .page-about .ab-tick,
  .page-about .ab-stage,
  .page-about .ab-link,
  .page-about .ab-step {
    transition-duration: 1ms;
  }
}