.page-about {
  --ab-hair-dark: rgba(240, 212, 138, 0.16);
  --ab-hair-light: rgba(10, 16, 38, 0.12);
  --ab-shadow-soft: 0 16px 40px rgba(10, 16, 38, 0.12);
  --ab-shadow-lift: 0 26px 56px rgba(10, 16, 38, 0.2);
  position: relative;
  background: var(--ink-night);
  color: var(--on-dark);
  font-family: var(--font-sans);
  overflow-x: clip;
}

.page-about .ab-dark { color: var(--on-dark); }
.page-about .ab-light { color: var(--on-light); }

/* ── 通用文本件 ───────────────────────────── */
.page-about .ab-eyebrow {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 0 0 16px;
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.16em;
}

.page-about .ab-eyebrow::before {
  content: "";
  flex: 0 0 auto;
  width: 28px;
  height: 2px;
  background: var(--crest-gold);
}

.page-about .ab-dark .ab-eyebrow { color: var(--on-dark-muted); }
.page-about .ab-light .ab-eyebrow { color: var(--ink-gold); }

.page-about .ab-h2 {
  margin: 0;
  font-size: var(--step-2);
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -0.015em;
}

.page-about .ab-lede {
  margin: 20px 0 0;
  max-width: 62ch;
  font-size: 1.0625rem;
  line-height: 1.9;
}

.page-about .ab-dark .ab-lede { color: var(--on-dark-muted); }
.page-about .ab-light .ab-lede { color: var(--on-light-muted); }

.page-about .ab-sec-head { max-width: 68ch; }

/* ── 左侧固定章节刻度 ─────────────────────── */
.page-about .ab-rail {
  position: fixed;
  top: 50%;
  left: 16px;
  z-index: 5;
  display: none;
  flex-direction: column;
  align-items: center;
  gap: 14px;
  padding: 20px 11px;
  transform: translateY(-50%);
  background: rgba(10, 16, 38, 0.88);
  border: 1px solid var(--ab-hair-dark);
  border-radius: 999px;
  backdrop-filter: blur(10px);
}

.page-about .ab-rail a {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 26px;
  color: var(--on-dark-muted);
  text-decoration: none;
  transition: color 0.3s var(--ease);
}

.page-about .ab-rail a::after {
  content: "";
  position: absolute;
  right: -6px;
  width: 10px;
  height: 1px;
  background: currentColor;
  opacity: 0.5;
  transition: width 0.3s var(--ease), opacity 0.3s var(--ease);
}

.page-about .ab-rail-num {
  font-family: var(--font-num);
  font-weight: 200;
  font-size: 0.8125rem;
  letter-spacing: 0.04em;
}

.page-about .ab-rail a:hover { color: var(--ice-white); }

.page-about .ab-rail a.is-active {
  color: var(--crest-gold);
}

.page-about .ab-rail a.is-active::after {
  width: 22px;
  opacity: 1;
}

@media (min-width: 1420px) {
  .page-about .ab-rail { display: flex; }
}

/* ── 01 首屏 ──────────────────────────────── */
.page-about .ab-hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  padding: calc(var(--header-h) + clamp(48px, 7vw, 88px)) 0 clamp(64px, 9vw, 120px);
  background:
    radial-gradient(120% 100% at 88% 0%, rgba(124, 90, 224, 0.32), transparent 60%),
    linear-gradient(172deg, var(--ink-night) 0%, var(--deep-cloud) 52%, var(--night-purple) 100%);
}

.page-about .ab-hero-media {
  position: absolute;
  inset: 0;
  z-index: -1;
}

.page-about .ab-hero-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.42;
}

.page-about .ab-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background: linear-gradient(96deg, rgba(10, 16, 38, 0.96) 0%, rgba(10, 16, 38, 0.82) 44%, rgba(19, 32, 63, 0.34) 100%);
}

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

.page-about .ab-crumb {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 clamp(30px, 5vw, 56px);
  font-size: 0.8125rem;
  letter-spacing: 0.04em;
  color: var(--on-dark-muted);
}

.page-about .ab-crumb a {
  color: var(--pale-gold);
  text-decoration: none;
}

.page-about .ab-crumb a:hover { text-decoration: underline; }

.page-about .ab-hero .ab-eyebrow { color: var(--pale-gold); }

.page-about .ab-hero-title {
  margin: 0;
  max-width: 15em;
  font-size: var(--step-display);
  font-weight: 900;
  line-height: 1.05;
  letter-spacing: -0.025em;
  color: var(--ice-white);
}

.page-about .ab-hero-lede {
  margin: clamp(22px, 3vw, 34px) 0 0;
  max-width: 46em;
  font-size: clamp(1rem, 1.15vw, 1.125rem);
  line-height: 1.95;
  color: var(--on-dark-muted);
}

.page-about .ab-hero-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 30px 22px;
  margin: clamp(44px, 6vw, 76px) 0 0;
  padding: clamp(28px, 4vw, 40px) 0 0;
  border-top: 1px solid var(--ab-hair-dark);
}

.page-about .ab-hero-stats > div { min-width: 0; }

.page-about .ab-hero-stats dt {
  font-family: var(--font-num);
  font-weight: 200;
  font-size: clamp(2.2rem, 5vw, 3.4rem);
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--pale-gold);
}

.page-about .ab-hero-stats dd {
  margin: 12px 0 0;
  font-size: 0.875rem;
  line-height: 1.6;
  color: var(--on-dark-muted);
}

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

/* ── 02 服务能力 ──────────────────────────── */
.page-about .ab-cap {
  position: relative;
  overflow: hidden;
  padding: var(--rhythm-2) 0 var(--rhythm-2);
  background: var(--warm-paper);
}

.page-about .ab-cap::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--crest-gold) 0%, var(--aurora-purple) 40%, rgba(217, 169, 60, 0) 86%);
  transform: skewY(-0.4deg);
  transform-origin: 0 0;
}

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

.page-about .ab-cap-figure {
  margin: 0;
  border-radius: 22px 22px 22px 5px;
  overflow: hidden;
  box-shadow: var(--ab-shadow-soft);
  aspect-ratio: 16 / 9;
}

.page-about .ab-cap-figure img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

@media (min-width: 900px) {
  .page-about .ab-cap-head {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.76fr);
    align-items: end;
  }
}

.page-about .ab-track-wrap {
  margin-top: clamp(36px, 5vw, 56px);
  overflow-x: auto;
  overflow-y: hidden;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
  scrollbar-color: var(--crest-gold) transparent;
}

.page-about .ab-track {
  display: flex;
  gap: 18px;
  width: max-content;
  margin: 0;
  padding: 8px max(var(--shell-pad), calc((100vw - var(--shell-max)) / 2)) 26px;
  list-style: none;
  scroll-snap-type: x proximity;
}

.page-about .ab-track:focus-visible {
  outline: 2px solid var(--crest-gold);
  outline-offset: -2px;
}

.page-about .ab-cap-item {
  flex: 0 0 min(82vw, 348px);
  scroll-snap-align: start;
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: 30px 28px 32px;
  background: var(--ice-white);
  border-radius: 22px 22px 22px 5px;
  box-shadow: inset 0 0 0 1px rgba(10, 16, 38, 0.06);
  transition: transform 0.4s var(--ease), box-shadow 0.4s var(--ease);
}

@media (hover: hover) {
  .page-about .ab-cap-item:hover {
    transform: translateY(-8px);
    box-shadow: var(--ab-shadow-lift);
  }
}

.page-about .ab-cap-no {
  font-family: var(--font-num);
  font-weight: 200;
  font-size: 2.4rem;
  line-height: 1;
  letter-spacing: -0.04em;
  color: var(--ink-gold);
}

.page-about .ab-cap-item h3 {
  margin: 0;
  font-size: 1.25rem;
  font-weight: 800;
  letter-spacing: 0.01em;
  color: var(--on-light);
}

.page-about .ab-cap-item p {
  margin: 0;
  font-size: 0.9375rem;
  line-height: 1.85;
  color: var(--on-light-muted);
}

.page-about .ab-cap-item .ab-cap-note {
  margin-top: auto;
  padding-top: 16px;
  border-top: 1px dashed var(--ab-hair-light);
  font-size: 0.875rem;
  line-height: 1.75;
  color: var(--ink-gold);
}

.page-about .ab-cap-foot {
  margin: 4px 0 0;
  font-size: 0.9375rem;
  line-height: 1.9;
  color: var(--on-light-muted);
}

/* ── 03 覆盖与规模 ────────────────────────── */
.page-about .ab-scale {
  padding: var(--rhythm-2) 0 var(--rhythm-3);
  background: var(--ice-white);
}

.page-about .ab-scale-figure {
  margin: clamp(32px, 4vw, 48px) 0 0;
  height: clamp(190px, 30vw, 380px);
  border-radius: 24px 24px 24px 6px;
  overflow: hidden;
  box-shadow: var(--ab-shadow-soft);
}

.page-about .ab-scale-figure img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.page-about .ab-scale-grid {
  display: grid;
  gap: clamp(34px, 4vw, 56px);
  margin-top: clamp(38px, 5vw, 60px);
}

@media (min-width: 940px) {
  .page-about .ab-scale-grid {
    grid-template-columns: minmax(0, 0.82fr) minmax(0, 1.18fr);
    align-items: center;
  }
}

.page-about .ab-donut-panel {
  position: relative;
  display: grid;
  place-items: center;
  padding: clamp(12px, 2vw, 24px);
}

.page-about .ab-donut {
  width: min(320px, 76vw);
  height: auto;
  overflow: visible;
}

.page-about .ab-donut-track {
  stroke: rgba(10, 16, 38, 0.08);
}

.page-about .ab-arc {
  transition: stroke-width 0.3s var(--ease), opacity 0.3s var(--ease);
}

.page-about .ab-arc--gold { stroke: var(--crest-gold); }
.page-about .ab-arc--aurora { stroke: var(--aurora-purple); }
.page-about .ab-arc--ice { stroke: var(--ice-blue); }
.page-about .ab-arc--mist { stroke: var(--mist-blue); }

.page-about .ab-arc:hover { stroke-width: 24; }

.page-about .ab-donut-center {
  position: absolute;
  top: 50%;
  left: 50%;
  display: grid;
  place-items: center;
  text-align: center;
  transform: translate(-50%, -50%);
  pointer-events: none;
}

.page-about .ab-donut-center b {
  display: block;
  font-family: var(--font-num);
  font-weight: 200;
  font-size: clamp(2.4rem, 5vw, 3.2rem);
  line-height: 1;
  letter-spacing: -0.04em;
  color: var(--crest-gold);
}

.page-about .ab-donut-center span {
  display: block;
  margin-top: 8px;
  font-size: 0.75rem;
  letter-spacing: 0.2em;
  color: var(--on-light-muted);
}

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

@media (min-width: 620px) {
  .page-about .ab-team-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.page-about .ab-team {
  padding: 20px 20px 22px;
  background: rgba(255, 255, 255, 0.74);
  border-left: 3px solid var(--crest-gold);
  border-radius: 4px 16px 16px 4px;
  box-shadow: inset 0 0 0 1px rgba(10, 16, 38, 0.06);
}

.page-about .ab-team:nth-child(2) { border-left-color: var(--aurora-purple); }
.page-about .ab-team:nth-child(3) { border-left-color: var(--ice-blue); }
.page-about .ab-team:nth-child(4) { border-left-color: var(--mist-blue); }

.page-about .ab-team h3 {
  margin: 0 0 8px;
  font-size: 1rem;
  font-weight: 800;
  letter-spacing: 0.02em;
  color: var(--on-light);
}

.page-about .ab-team p {
  margin: 0;
  font-size: 0.875rem;
  line-height: 1.8;
  color: var(--on-light-muted);
}

/* ── 04 版本节奏 ──────────────────────────── */
.page-about .ab-stage {
  padding: var(--rhythm-3) 0;
  background:
    radial-gradient(90% 70% at 82% 6%, rgba(124, 90, 224, 0.22), transparent 62%),
    linear-gradient(180deg, #060A18 0%, var(--ink-night) 46%, var(--deep-cloud) 100%);
}

.page-about .ab-timeline {
  display: grid;
  gap: clamp(26px, 4vw, 42px);
  margin: clamp(42px, 5vw, 66px) 0 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-tl-item {
  display: grid;
  gap: 10px 24px;
  padding-bottom: clamp(22px, 3vw, 34px);
  border-bottom: 1px solid var(--ab-hair-dark);
}

@media (min-width: 820px) {
  .page-about .ab-tl-item {
    grid-template-columns: 120px minmax(0, 1fr);
    align-items: start;
  }
}

.page-about .ab-tl-no {
  font-family: var(--font-num);
  font-weight: 200;
  font-size: clamp(2.6rem, 6vw, 4rem);
  line-height: 0.9;
  letter-spacing: -0.05em;
  color: var(--pale-gold);
  opacity: 0.72;
}

.page-about .ab-tl-body h3 {
  margin: 0 0 10px;
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--ice-white);
}

.page-about .ab-tl-body p {
  margin: 0;
  max-width: 62ch;
  font-size: 0.95rem;
  line-height: 1.9;
  color: var(--on-dark-muted);
}

.page-about .ab-cadence {
  display: grid;
  gap: 14px;
  margin-top: clamp(40px, 5vw, 64px);
}

@media (min-width: 860px) {
  .page-about .ab-cadence {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .ab-cadence-item {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: clamp(22px, 3vw, 30px);
  background: rgba(247, 243, 234, 0.045);
  border: 1px solid var(--ab-hair-dark);
  border-radius: 16px;
}

.page-about .ab-cadence-key {
  font-size: 1.125rem;
  font-weight: 800;
  letter-spacing: 0.02em;
  color: var(--pale-gold);
}

.page-about .ab-cadence-val {
  font-size: 0.9rem;
  line-height: 1.8;
  color: var(--on-dark-muted);
}

/* ── 05 协作生态 ──────────────────────────── */
.page-about .ab-eco {
  padding: var(--rhythm-2) 0 var(--rhythm-3);
  background: linear-gradient(178deg, var(--deep-cloud) 0%, var(--night-purple) 54%, var(--ink-night) 100%);
}

.page-about .ab-eco-grid {
  display: grid;
  gap: clamp(18px, 2.4vw, 26px);
  margin-top: clamp(36px, 5vw, 56px);
}

@media (min-width: 820px) {
  .page-about .ab-eco-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .ab-eco-card {
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: clamp(24px, 3vw, 32px);
  background: rgba(10, 16, 38, 0.44);
  border: 1px solid var(--ab-hair-dark);
  border-radius: 20px 20px 20px 6px;
  transition: transform 0.4s var(--ease), border-color 0.4s var(--ease);
}

@media (hover: hover) {
  .page-about .ab-eco-card:hover {
    transform: translateY(-8px);
    border-color: rgba(217, 169, 60, 0.5);
  }
}

.page-about .ab-eco-tag {
  align-self: flex-start;
  display: inline-flex;
  align-items: center;
  padding: 6px 14px;
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.1em;
}

.page-about .ab-eco-tag--gold {
  background: rgba(217, 169, 60, 0.16);
  color: var(--pale-gold);
}

.page-about .ab-eco-tag--aurora {
  background: rgba(124, 90, 224, 0.24);
  color: #C9B8FF;
}

.page-about .ab-eco-tag--ice {
  background: rgba(168, 196, 232, 0.16);
  color: var(--ice-blue);
}

.page-about .ab-eco-card h3 {
  margin: 0;
  font-size: 1.125rem;
  font-weight: 800;
  line-height: 1.5;
  color: var(--ice-white);
}

.page-about .ab-eco-card p {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.85;
  color: var(--on-dark-muted);
}

.page-about .ab-eco-note {
  margin: clamp(28px, 4vw, 42px) 0 0;
  max-width: 68ch;
  font-size: 0.95rem;
  line-height: 1.9;
  color: var(--on-dark-muted);
}

.page-about .ab-eco-note .link-inline { color: var(--pale-gold); }

/* ── 06 选择理由 ──────────────────────────── */
.page-about .ab-why {
  padding: var(--rhythm-3) 0;
  background: linear-gradient(180deg, var(--warm-paper) 0%, var(--ice-white) 100%);
}

.page-about .ab-why-list {
  display: grid;
  gap: clamp(22px, 3vw, 32px);
  margin: clamp(36px, 5vw, 56px) 0 0;
  padding: 0;
  list-style: none;
}

@media (min-width: 860px) {
  .page-about .ab-why-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .ab-why-item {
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding-top: 24px;
  border-top: 2px solid var(--ink-night);
  transition: border-color 0.3s var(--ease);
}

@media (hover: hover) {
  .page-about .ab-why-item:hover { border-top-color: var(--crest-gold); }
}

.page-about .ab-why-no {
  font-family: var(--font-num);
  font-weight: 200;
  font-size: 2rem;
  line-height: 1;
  letter-spacing: -0.04em;
  color: var(--ink-gold);
}

.page-about .ab-why-item h3 {
  margin: 0;
  font-size: 1.125rem;
  font-weight: 800;
  color: var(--on-light);
}

.page-about .ab-why-item p {
  margin: 0;
  font-size: 0.9375rem;
  line-height: 1.9;
  color: var(--on-light-muted);
}

.page-about .ab-why .link-inline { color: var(--ink-gold); }

.page-about .ab-cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: clamp(40px, 5vw, 60px);
}

.page-about .ab-cta-row .btn {
  min-width: 168px;
  justify-content: center;
}

/* ── 窄屏收敛 ─────────────────────────────── */
@media (max-width: 520px) {
  .page-about .ab-hero-stats {
    gap: 24px 16px;
  }

  .page-about .ab-hero-stats dd { font-size: 0.8125rem; }

  .page-about .ab-cap-item {
    flex: 0 0 84vw;
    padding: 26px 22px 28px;
  }

  .page-about .ab-tl-no { font-size: 2.4rem; }

  .page-about .ab-cta-row .btn {
    min-width: 0;
    flex: 1 1 100%;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-cap-item,
  .page-about .ab-eco-card,
  .page-about .ab-why-item,
  .page-about .ab-arc,
  .page-about .ab-rail a,
  .page-about .ab-rail a::after {
    transition: none;
  }

  .page-about .ab-cap-item:hover,
  .page-about .ab-eco-card:hover {
    transform: none;
  }
}