.page-about {
  --ab-gap: clamp(44px, 7vw, 88px);
  --ab-band-pad: clamp(40px, 6vw, 76px);
  background: var(--ink-900);
  color: var(--paper);
  font-family: var(--font-body);
  overflow-x: clip;
  padding-bottom: clamp(40px, 6vw, 72px);
}

.page-about .ab-index {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--gold);
  margin: 0 0 12px;
}

.page-about .breadcrumb {
  padding-top: clamp(14px, 3vw, 26px);
}

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

.page-about .breadcrumb__link:hover,
.page-about .breadcrumb__link:focus-visible {
  color: var(--gold);
}

.page-about .breadcrumb__link[aria-current="page"] {
  color: var(--paper);
}

/* ---------- 首屏 ---------- */
.page-about .ab-intro {
  position: relative;
  overflow: hidden;
  padding-block: clamp(18px, 3vw, 30px) var(--ab-gap);
}

.page-about .ab-intro::before {
  content: "";
  position: absolute;
  left: 30%;
  right: -10%;
  top: 62%;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--gold-deep), transparent);
  transform: rotate(-12deg);
  opacity: 0.55;
  pointer-events: none;
}

.page-about .ab-intro__grid {
  display: grid;
  gap: clamp(24px, 4vw, 48px);
  align-items: center;
}

.page-about .ab-kicker {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  font-family: var(--font-ui);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--mist);
  margin: 0 0 18px;
}

.page-about .ab-intro h1 {
  font-family: var(--font-display);
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1.16;
  font-size: clamp(32px, 6.2vw, 66px);
  margin: 0 0 20px;
}

.page-about .ab-lead {
  font-size: clamp(16px, 1.6vw, 18px);
  line-height: 1.85;
  max-width: 34em;
  margin: 0 0 26px;
  color: var(--paper);
  opacity: 0.9;
}

.page-about .ab-facts {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
  gap: 16px 18px;
}

.page-about .ab-facts li {
  border-top: 1px solid var(--rule);
  padding-top: 12px;
}

.page-about .ab-facts b {
  display: block;
  font-family: var(--font-mono);
  font-weight: 500;
  font-size: clamp(20px, 2.4vw, 28px);
  color: var(--gold);
  line-height: 1.2;
}

.page-about .ab-facts span {
  display: block;
  margin-top: 5px;
  font-family: var(--font-ui);
  font-size: 12.5px;
  letter-spacing: 0.03em;
  color: var(--mist);
}

.page-about .ab-intro__media {
  margin: 0;
  min-width: 0;
}

.page-about .ab-intro__media .media-frame__img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 通用章节 ---------- */
.page-about .ab-section {
  padding-block: var(--ab-gap);
}

.page-about .ab-section__head {
  max-width: 46em;
  margin-bottom: clamp(24px, 4vw, 44px);
}

.page-about .ab-section__head h2 {
  font-family: var(--font-display);
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1.28;
  font-size: clamp(24px, 3.4vw, 38px);
  margin: 0 0 12px;
}

.page-about .ab-section__head p {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.9;
  color: var(--mist);
}

.page-about .ab-figure {
  margin: clamp(26px, 4vw, 40px) 0 0;
  min-width: 0;
}

.page-about .ab-figure .media-frame__img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .ab-figure__cap {
  margin-top: 10px;
  font-family: var(--font-ui);
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--mist);
}

/* ---------- 时间线 ---------- */
.page-about .ab-timeline__layout {
  display: grid;
  gap: clamp(20px, 3vw, 32px);
}

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

.page-about .ab-rail__list::-webkit-scrollbar {
  display: none;
}

.page-about .ab-rail a {
  display: block;
  padding: 6px 12px;
  border: 1px solid var(--rule);
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--mist);
  text-decoration: none;
  white-space: nowrap;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .ab-rail a:hover,
.page-about .ab-rail a:focus-visible {
  color: var(--gold);
  border-color: var(--gold);
}

.page-about .ab-nodes {
  list-style: none;
  margin: 0;
  padding: 0;
  min-width: 0;
}

.page-about .ab-node {
  position: relative;
  padding: 0 0 clamp(26px, 4vw, 38px) 26px;
  border-left: 1px solid var(--rule);
  scroll-margin-top: 120px;
}

.page-about .ab-node:last-child {
  padding-bottom: 0;
  border-left-color: transparent;
}

.page-about .ab-node::before {
  content: "";
  position: absolute;
  left: -5px;
  top: 8px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--jade);
  box-shadow: 0 0 0 4px rgba(123, 196, 168, 0.14);
}

.page-about .ab-node__year {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--gold);
}

.page-about .ab-node h3 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(18px, 2.2vw, 23px);
  letter-spacing: -0.01em;
  margin: 0 0 8px;
}

.page-about .ab-node p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--mist);
  max-width: 42em;
}

/* ---------- 团队主题带 ---------- */
.page-about .ab-band {
  position: relative;
  overflow: hidden;
  margin-block: clamp(20px, 4vw, 40px);
  padding-block: var(--ab-band-pad);
  background: linear-gradient(180deg, var(--ink-700), var(--ink-850));
  border-top: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
}

.page-about .ab-band::before {
  content: "";
  position: absolute;
  left: -5%;
  right: -5%;
  top: 34%;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(168, 118, 47, 0.65), transparent);
  transform: rotate(-12deg);
  pointer-events: none;
}

.page-about .ab-team {
  display: grid;
  gap: 16px;
  align-items: end;
}

.page-about .ab-team__card {
  position: relative;
  padding: 22px 20px;
  background: rgba(246, 239, 227, 0.05);
  border: 1px solid var(--rule-soft);
  clip-path: polygon(16px 0, 100% 0, 100% calc(100% - 16px), calc(100% - 16px) 100%, 0 100%, 0 16px);
}

.page-about .ab-team__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(30px, 4vw, 42px);
  line-height: 1;
  color: var(--gold);
}

.page-about .ab-team__num small {
  font-size: 13px;
  margin-left: 4px;
  color: var(--mist);
}

.page-about .ab-team__role {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 18px;
  letter-spacing: -0.01em;
  margin: 12px 0 10px;
}

.page-about .ab-team__card p {
  margin: 0 0 12px;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .ab-team__card ul {
  margin: 0;
  padding-left: 16px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--paper);
  opacity: 0.86;
}

.page-about .ab-team__card li + li {
  margin-top: 4px;
}

/* ---------- 三道流程 ---------- */
.page-about .ab-steps {
  display: grid;
  gap: 14px;
}

.page-about .ab-step {
  padding: 24px 22px;
  background: linear-gradient(155deg, rgba(227, 178, 92, 0.16), rgba(18, 49, 76, 0.85));
  clip-path: polygon(18px 0, 100% 0, 100% calc(100% - 18px), calc(100% - 18px) 100%, 0 100%, 0 18px);
}

.page-about .ab-step__no {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--gold);
}

.page-about .ab-step h3 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 19px;
  margin: 10px 0 8px;
}

.page-about .ab-step p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--paper);
  opacity: 0.84;
}

.page-about .ab-note {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin: 22px 0 0;
  font-family: var(--font-ui);
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--mist);
}

/* ---------- 服务指标 ---------- */
.page-about .ab-metrics {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px 16px;
}

.page-about .ab-metric {
  border-left: 1px solid var(--rule);
  padding-left: 16px;
}

.page-about .ab-metric__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(24px, 3.2vw, 36px);
  line-height: 1.1;
  color: var(--gold);
  letter-spacing: -0.01em;
}

.page-about .ab-metric__unit {
  font-size: 0.63em;
  margin-left: 2px;
  color: var(--gold-deep);
}

.page-about .ab-metric__label {
  margin: 8px 0 6px;
  font-family: var(--font-ui);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--paper);
}

.page-about .ab-metric p:last-child {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--mist);
}

/* ---------- 合作生态 ---------- */
.page-about .ab-eco {
  display: grid;
  gap: 18px;
}

.page-about .ab-eco__card {
  padding: 24px 22px;
  background: rgba(246, 239, 227, 0.05);
  border: 1px solid var(--rule-soft);
  clip-path: polygon(18px 0, 100% 0, 100% calc(100% - 18px), calc(100% - 18px) 100%, 0 100%, 0 18px);
}

.page-about .ab-eco__card h3 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 19px;
  margin: 0 0 14px;
}

.page-about .ab-eco__list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .ab-eco__list li {
  position: relative;
  padding-left: 18px;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--mist);
}

.page-about .ab-eco__list li + li {
  margin-top: 10px;
}

.page-about .ab-eco__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--jade);
}

.page-about .ab-eco__list .mono {
  color: var(--gold);
  font-size: 15px;
}

.page-about .ab-honor__line {
  margin: 0 0 12px;
}

.page-about .ab-eco__card--honor p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--mist);
}

/* ---------- 站点信息 ---------- */
.page-about .ab-info-panel {
  background: var(--paper);
  color: var(--ink-black);
  padding: clamp(20px, 4vw, 40px);
}

.page-about .ab-info {
  margin: 0;
  border-top: 1px solid rgba(6, 16, 26, 0.14);
}

.page-about .ab-info__row {
  display: grid;
  gap: 4px;
  padding: 16px 0;
  border-bottom: 1px solid rgba(6, 16, 26, 0.14);
}

.page-about .ab-info dt {
  font-family: var(--font-ui);
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--gold-deep);
}

.page-about .ab-info dd {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-black);
  overflow-wrap: anywhere;
}

.page-about .ab-info dd a {
  color: var(--ink-black);
  text-decoration: underline;
  text-decoration-color: var(--gold-deep);
  text-underline-offset: 3px;
}

.page-about .ab-info dd a:hover,
.page-about .ab-info dd a:focus-visible {
  color: var(--gold-deep);
}

/* ---------- 收束 ---------- */
.page-about .ab-cta {
  display: grid;
  gap: 18px;
  margin-top: clamp(32px, 5vw, 56px);
  padding-top: clamp(26px, 4vw, 44px);
  border-top: 1px solid var(--rule);
}

.page-about .ab-cta h2 {
  font-family: var(--font-display);
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1.35;
  font-size: clamp(21px, 2.8vw, 30px);
  margin: 0 0 10px;
}

.page-about .ab-cta p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--mist);
  max-width: 40em;
}

.page-about .ab-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
}

/* ---------- 桌面增强 ---------- */
@media (min-width: 820px) {
  .page-about .ab-team {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
  }

  .page-about .ab-team__card:nth-child(1) {
    min-height: 288px;
  }

  .page-about .ab-team__card:nth-child(2) {
    min-height: 240px;
  }

  .page-about .ab-team__card:nth-child(3) {
    min-height: 324px;
  }

  .page-about .ab-steps {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
  }

  .page-about .ab-eco {
    grid-template-columns: 1.15fr 0.85fr;
    gap: clamp(20px, 3vw, 36px);
  }

  .page-about .ab-cta {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
  }

  .page-about .ab-cta__actions {
    justify-content: flex-end;
  }
}

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

  .page-about .ab-timeline__layout {
    grid-template-columns: 92px minmax(0, 1fr);
    gap: clamp(24px, 4vw, 56px);
  }

  .page-about .ab-rail {
    position: sticky;
    top: 110px;
    align-self: start;
  }

  .page-about .ab-rail__list {
    flex-direction: column;
    overflow: visible;
    gap: 0;
    padding: 0;
  }

  .page-about .ab-rail a {
    border: 0;
    border-left: 1px solid var(--rule);
    border-radius: 0;
    padding: 10px 0 10px 14px;
    font-size: 14px;
  }

  .page-about .ab-metrics {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 20px;
  }

  .page-about .ab-info__row {
    grid-template-columns: 190px minmax(0, 1fr);
    gap: 20px;
    align-items: baseline;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-rail a {
    transition: none;
  }
}