.page-about {
  --about-rail-w: 204px;
  --about-gap: clamp(28px, 4vw, 56px);
  --about-hair: rgba(28, 75, 88, 0.55);
  --about-hair-strong: rgba(28, 75, 88, 0.9);
  --about-text: var(--ab-white);
  --about-dim: var(--ab-muted);
  --about-ink-2: var(--ab-slate);
  --about-violet-wash: rgba(123, 92, 255, 0.1);
  --about-coral-line: rgba(255, 106, 69, 0.55);
  --about-pulse-tint: rgba(53, 224, 200, 0.14);
}

/* ---------- 面包屑与首屏 ---------- */
.page-about .ab-breadcrumb {
  padding: 22px 0 0;
  font-size: 13px;
  color: var(--about-dim);
}

.page-about .ab-breadcrumb__link {
  color: var(--ab-violet-soft);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 140ms ease, color 140ms ease;
}

.page-about .ab-breadcrumb__link:hover,
.page-about .ab-breadcrumb__link:focus-visible {
  color: var(--ab-white);
  border-bottom-color: var(--ab-violet-soft);
}

.page-about .ab-breadcrumb__sep {
  margin: 0 8px;
  color: var(--ab-grid);
}

.page-about .about-hero {
  position: relative;
  padding: clamp(28px, 4vw, 48px) 0 clamp(26px, 3.4vw, 40px);
  border-bottom: 1px solid var(--about-hair-strong);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: -20% -10% auto auto;
  width: 46%;
  min-width: 260px;
  aspect-ratio: 1 / 1;
  background: radial-gradient(circle at 60% 40%, rgba(123, 92, 255, 0.28), transparent 62%);
  pointer-events: none;
  z-index: 0;
}

.page-about .about-hero > * {
  position: relative;
  z-index: 1;
}

.page-about .ab-eyebrow {
  margin: 0 0 14px;
  font: 500 12px/1 var(--ab-mono);
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--ab-pulse);
}

.page-about .ab-page-title {
  margin: 0;
  font-family: var(--ab-sans);
  font-weight: 800;
  font-size: clamp(34px, 5.6vw, 62px);
  line-height: 1.08;
  letter-spacing: 0.06em;
  color: var(--about-text);
  max-width: 16ch;
}

.page-about .ab-page-title::after {
  content: "";
  display: block;
  width: 96px;
  height: 2px;
  margin-top: 20px;
  background: linear-gradient(90deg, var(--ab-coral), var(--ab-violet));
}

.page-about .ab-lede {
  margin: 22px 0 0;
  max-width: 62ch;
  font-size: clamp(16px, 1.3vw, 18px);
  line-height: 1.85;
  color: var(--about-text);
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1px;
  margin-top: clamp(26px, 3.4vw, 40px);
  background: var(--about-hair);
  border: 1px solid var(--about-hair);
}

.page-about .about-stat {
  background: var(--about-ink-2);
  padding: 18px 20px 20px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  transition: background-color 160ms ease;
}

.page-about .about-stat:hover {
  background: #123541;
}

.page-about .about-stat__num {
  font-family: var(--ab-serif);
  font-weight: 700;
  font-size: clamp(28px, 3.6vw, 44px);
  line-height: 1;
  letter-spacing: 0.02em;
  color: var(--ab-white);
}

.page-about .about-stat__unit {
  margin-left: 3px;
  font-family: var(--ab-mono);
  font-size: 0.44em;
  letter-spacing: 0.08em;
  color: var(--ab-pulse);
}

.page-about .about-stat__label {
  font: 500 12px/1.4 var(--ab-mono);
  letter-spacing: 0.1em;
  color: var(--about-dim);
}

.page-about .about-hero__strip {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
  margin-top: 22px;
  padding-top: 16px;
  border-top: 1px solid var(--about-hair);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--about-dim);
}

.page-about .about-hero__strip .ab-mono {
  position: relative;
  padding-left: 14px;
}

.page-about .about-hero__strip .ab-mono::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  width: 6px;
  height: 6px;
  margin-top: -3px;
  background: var(--ab-pulse);
  border-radius: 0;
}

/* ---------- 双栏布局 ---------- */
.page-about .about-layout {
  display: block;
  margin-top: clamp(32px, 4.4vw, 56px);
}

.page-about .about-rail {
  display: none;
}

.page-about .about-body {
  min-width: 0;
}

@media (min-width: 900px) {
  .page-about .about-layout {
    display: grid;
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: var(--about-gap);
    align-items: start;
  }

  .page-about .about-rail {
    display: block;
  }

  .page-about .about-rail__inner {
    position: sticky;
    top: 32px;
    padding-top: 6px;
    border-top: 2px solid var(--ab-coral);
  }
}

.page-about .about-rail__kicker {
  margin: 0 0 14px;
  font-size: 11px;
  letter-spacing: 0.22em;
  color: var(--ab-violet-soft);
}

.page-about .about-rail__nav {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 2px;
  border-left: 1px solid var(--about-hair);
}

.page-about .about-rail__link {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 8px 0 8px 14px;
  margin-left: -1px;
  border-left: 2px solid transparent;
  color: var(--about-dim);
  text-decoration: none;
  font-size: 14px;
  line-height: 1.5;
  transition: color 140ms ease, border-color 140ms ease, background-color 140ms ease;
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--ab-white);
  border-left-color: var(--ab-violet);
  background: var(--about-violet-wash);
}

.page-about .about-rail__num {
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--ab-grid);
}

.page-about .about-rail__link:hover .about-rail__num,
.page-about .about-rail__link:focus-visible .about-rail__num {
  color: var(--ab-coral);
}

.page-about .about-rail__meta {
  margin-top: 22px;
  padding-top: 14px;
  border-top: 1px solid var(--about-hair);
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.page-about .about-rail__meta p {
  margin: 0;
  font-size: 11px;
  line-height: 1.6;
  letter-spacing: 0.06em;
  color: var(--ab-grid);
}

/* ---------- 章节 ---------- */
.page-about .about-chapter {
  padding: 0 0 clamp(36px, 4.6vw, 56px);
  margin-bottom: clamp(36px, 4.6vw, 56px);
  border-bottom: 1px solid var(--about-hair);
}

.page-about .about-chapter:last-of-type {
  border-bottom: 0;
}

.page-about .about-chapter__head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 20px;
}

.page-about .about-chapter__num {
  flex: 0 0 auto;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--ab-coral);
  padding: 4px 8px;
  border: 1px solid var(--about-coral-line);
  line-height: 1;
}

.page-about .ab-section__title {
  margin: 0;
  font-family: var(--ab-serif);
  font-weight: 600;
  font-size: clamp(22px, 2.6vw, 32px);
  line-height: 1.35;
  letter-spacing: 0.01em;
  color: var(--ab-white);
}

.page-about .about-p {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--about-text);
  max-width: 66ch;
}

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

.page-about .about-mono-line {
  margin: 18px 0 0;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--ab-violet-soft);
}

/* 清单 */
.page-about .about-checklist {
  list-style: none;
  margin: 6px 0 22px;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--about-hair);
  border: 1px solid var(--about-hair);
}

.page-about .about-checklist li {
  position: relative;
  background: var(--about-ink-2);
  padding: 14px 18px 14px 40px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--about-text);
}

.page-about .about-check {
  position: absolute;
  left: 16px;
  top: 21px;
  width: 10px;
  height: 10px;
  border: 1px solid var(--ab-pulse);
  background: var(--about-pulse-tint);
  box-shadow: 0 0 0 3px rgba(53, 224, 200, 0.06);
}

@media (min-width: 640px) {
  .page-about .about-checklist {
    grid-template-columns: 1fr 1fr;
  }
}

/* 分区编号格 */
.page-about .about-zone-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(148px, 1fr));
  gap: 1px;
  margin-top: 22px;
  background: var(--about-hair);
  border: 1px solid var(--about-hair);
}

.page-about .about-zone {
  position: relative;
  background: var(--about-ink-2);
  padding: 16px 16px 20px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-height: 88px;
  cursor: default;
  transition: background-color 160ms ease, box-shadow 160ms ease;
  outline: none;
}

.page-about .about-zone:hover,
.page-about .about-zone:focus-visible {
  background: #123541;
  box-shadow: inset 0 0 0 1px var(--ab-violet);
}

.page-about .about-zone__num {
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--ab-violet-soft);
  transition: color 140ms ease;
}

.page-about .about-zone:hover .about-zone__num,
.page-about .about-zone:focus-visible .about-zone__num {
  color: var(--ab-coral);
}

.page-about .about-zone__name {
  font-size: 15px;
  font-weight: 600;
  color: var(--ab-white);
  letter-spacing: 0.02em;
}

.page-about .about-zone__detail {
  font-size: 12px;
  line-height: 1.55;
  color: var(--ab-grid);
  opacity: 0;
  transform: translateY(-2px);
  transition: opacity 180ms ease, transform 180ms ease, color 180ms ease;
}

.page-about .about-zone:hover .about-zone__detail,
.page-about .about-zone:focus-visible .about-zone__detail {
  opacity: 1;
  transform: translateY(0);
  color: var(--ab-muted);
}

/* 规则章节 */
.page-about .about-rule-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 26px;
  align-items: start;
}

@media (min-width: 820px) {
  .page-about .about-rule-layout {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.72fr);
    gap: clamp(28px, 3.6vw, 48px);
  }
}

.page-about .about-rule-figure {
  margin: 0;
  border: 1px solid var(--about-hair);
  background: linear-gradient(155deg, rgba(123, 92, 255, 0.14), rgba(7, 27, 34, 0) 62%);
  padding: 14px;
}

.page-about .about-rule-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border: 1px solid var(--about-hair);
}

.page-about .about-rule-figure figcaption {
  margin-top: 12px;
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--ab-violet-soft);
}

.page-about .about-rule-tags {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 26px 0 0;
  padding: 0;
}

.page-about .about-rule-tag {
  font: 500 12px/1 var(--ab-mono);
  letter-spacing: 0.1em;
  padding: 9px 14px;
  color: var(--ab-white);
  border: 1px solid var(--about-hair-strong);
  background: rgba(14, 43, 53, 0.7);
  transition: border-color 140ms ease, color 140ms ease, background-color 140ms ease;
}

.page-about .about-rule-tag:hover {
  border-color: var(--ab-coral);
  color: var(--ab-coral);
  background: rgba(255, 106, 69, 0.08);
}

/* 取舍双列 */
.page-about .about-tradeoff {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  margin-top: 22px;
  background: var(--about-hair);
  border: 1px solid var(--about-hair);
}

@media (min-width: 720px) {
  .page-about .about-tradeoff {
    grid-template-columns: 1fr 1fr;
  }
}

.page-about .about-tradeoff__col {
  padding: 20px 22px 22px;
  background: var(--about-ink-2);
}

.page-about .about-tradeoff__col--keep {
  border-top: 2px solid var(--ab-pulse);
}

.page-about .about-tradeoff__col--drop {
  border-top: 2px solid var(--ab-coral);
}

.page-about .about-tradeoff__label {
  margin: 0 0 14px;
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--ab-muted);
}

.page-about .about-tradeoff__col--keep .about-tradeoff__label {
  color: var(--ab-pulse);
}

.page-about .about-tradeoff__col--drop .about-tradeoff__label {
  color: var(--ab-coral);
}

.page-about .about-tradeoff__col ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.page-about .about-tradeoff__col li {
  position: relative;
  padding-left: 18px;
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--about-text);
}

.page-about .about-tradeoff__col--keep li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 8px;
  height: 8px;
  background: var(--ab-pulse);
}

.page-about .about-tradeoff__col--drop li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  width: 10px;
  height: 1px;
  background: var(--ab-coral);
}

/* 团队 */
.page-about .about-team {
  display: grid;
  grid-template-columns: 1fr;
  gap: 26px;
  align-items: start;
}

@media (min-width: 820px) {
  .page-about .about-team {
    grid-template-columns: minmax(0, 1fr) minmax(0, 0.9fr);
    gap: clamp(28px, 3.6vw, 48px);
  }
}

.page-about .about-team__figure {
  margin: 0;
  border: 1px solid var(--about-hair);
  background: linear-gradient(200deg, rgba(53, 224, 200, 0.1), rgba(7, 27, 34, 0) 60%);
  padding: 14px;
}

.page-about .about-team__figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border: 1px solid var(--about-hair);
}

.page-about .about-team__figure figcaption {
  margin-top: 12px;
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--ab-pulse);
}

/* 时间轴 */
.page-about .about-timeline-section {
  position: relative;
  margin: 0 0 clamp(36px, 4.6vw, 56px);
  padding: clamp(30px, 4vw, 48px) clamp(18px, 2.6vw, 34px) clamp(34px, 4.4vw, 52px);
  border: 1px solid var(--about-hair);
  background: linear-gradient(180deg, rgba(4, 9, 11, 0.92), rgba(7, 27, 34, 0.96));
  overflow: hidden;
}

.page-about .about-timeline-bg {
  position: absolute;
  inset: 0;
  margin: 0;
  z-index: 0;
  pointer-events: none;
  opacity: 0.35;
}

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

.page-about .about-timeline-section > *:not(.about-timeline-bg) {
  position: relative;
  z-index: 1;
}

.page-about .about-chapter__head--onbg {
  margin-bottom: 18px;
}

.page-about .about-p--onbg {
  color: var(--about-text);
}

.page-about .about-timeline {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
}

.page-about .about-timeline__item {
  position: relative;
  display: grid;
  grid-template-columns: 62px minmax(0, 1fr);
  gap: 16px;
  padding: 18px 0 18px 0;
  border-top: 1px solid var(--about-hair);
  transition: background-color 160ms ease, border-color 160ms ease;
}

.page-about .about-timeline__item:last-child {
  border-bottom: 1px solid var(--about-hair);
}

.page-about .about-timeline__item:hover {
  background: rgba(123, 92, 255, 0.07);
  border-top-color: var(--ab-violet);
}

.page-about .about-timeline__year {
  font-size: 13px;
  letter-spacing: 0.12em;
  color: var(--ab-pulse);
  padding-top: 3px;
}

.page-about .about-timeline__title {
  margin: 0 0 6px;
  font-family: var(--ab-serif);
  font-weight: 600;
  font-size: 18px;
  line-height: 1.4;
  color: var(--ab-white);
  letter-spacing: 0.01em;
}

.page-about .about-timeline__body p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--about-dim);
  max-width: 62ch;
  transition: color 160ms ease;
}

.page-about .about-timeline__item:hover .about-timeline__body p {
  color: var(--about-text);
}

/* 协作 */
.page-about .about-partners {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  margin-top: 20px;
  background: var(--about-hair);
  border: 1px solid var(--about-hair);
}

@media (min-width: 720px) {
  .page-about .about-partners {
    grid-template-columns: 1fr 1fr;
  }

  .page-about .about-partners__block--wide {
    grid-column: 1 / -1;
  }
}

.page-about .about-partners__block {
  background: var(--about-ink-2);
  padding: 22px 22px 24px;
  transition: background-color 160ms ease;
}

.page-about .about-partners__block:hover {
  background: #123541;
}

.page-about .about-partners__num {
  margin: 0;
  font-family: var(--ab-serif);
  font-weight: 700;
  font-size: clamp(30px, 3.6vw, 44px);
  line-height: 1;
  color: var(--ab-coral);
}

.page-about .about-partners__label {
  margin: 6px 0 12px;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--ab-violet-soft);
}

.page-about .about-partners__block > p:last-child {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--about-text);
  max-width: 62ch;
}

.page-about .about-zone-grid + .about-mono-line {
  padding-top: 4px;
}

/* CTA */
.page-about .about-cta {
  margin-top: clamp(20px, 3vw, 36px);
  padding: clamp(26px, 3.4vw, 40px) clamp(20px, 2.6vw, 34px);
  border: 1px solid var(--about-hair-strong);
  background: linear-gradient(120deg, rgba(123, 92, 255, 0.16), rgba(255, 106, 69, 0.08) 60%, rgba(7, 27, 34, 0.9));
}

.page-about .about-cta__kicker {
  margin: 0 0 12px;
  font-size: 11px;
  letter-spacing: 0.22em;
  color: var(--ab-coral);
}

.page-about .about-cta__title {
  margin: 0 0 14px;
  font-family: var(--ab-serif);
  font-weight: 600;
  font-size: clamp(22px, 2.6vw, 30px);
  line-height: 1.3;
  color: var(--ab-white);
}

.page-about .about-cta .ab-btn-row {
  margin-top: 22px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .about-cta .ab-btn {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
}

@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition-duration: 0.001ms !important;
    animation-duration: 0.001ms !important;
  }
}