.page-about {
  --ab-gold-soft: rgba(216, 169, 75, 0.14);
  --ab-steel-soft: rgba(38, 54, 92, 0.72);
  background: var(--ink);
  color: var(--paper);
  font-family: var(--font-sans);
  line-height: 1.85;
  overflow-x: hidden;
}

.page-about h1,
.page-about h2,
.page-about h3 {
  font-family: var(--font-sans);
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about p {
  margin: 0 0 1rem;
  font-size: var(--fs-16);
  color: var(--mist);
}

.page-about a {
  color: var(--gold);
}

.page-about .num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

/* ---------- 面包屑 ---------- */
.page-about .ab-crumb {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: var(--fs-12);
  letter-spacing: 0.08em;
  color: var(--mist);
  margin-bottom: clamp(1.5rem, 5vw, 2.5rem);
}

.page-about .ab-crumb a {
  color: var(--mist);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

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

/* ---------- 首屏封面 ---------- */
.page-about .ab-hero {
  position: relative;
  padding-block: clamp(1.25rem, 4vw, 2rem) clamp(2.5rem, 8vw, 5rem);
  border-bottom: 1px solid var(--steel);
  background:
    radial-gradient(90% 85% at 0% 0%, var(--ab-gold-soft), transparent 62%),
    radial-gradient(80% 80% at 100% 0%, rgba(26, 23, 64, 0.92), transparent 64%),
    var(--ink);
  overflow: hidden;
}

.page-about .ab-hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 2rem;
}

.page-about .ab-h1 {
  font-size: clamp(2rem, 8vw, 4rem);
  font-weight: 900;
  line-height: 1.08;
  margin: 0.35rem 0 1.1rem;
}

.page-about .ab-lede {
  font-size: var(--fs-16);
  color: var(--mist);
  max-width: 34em;
}

.page-about .ab-hero-actions {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.6rem;
  margin: 1.5rem 0 0;
}

.page-about .ab-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem 1.25rem;
  margin: 1.75rem 0 0;
  padding: 1.25rem 0 0;
  border-top: 1px solid var(--gold-line);
}

.page-about .ab-fact dt {
  font-size: var(--fs-12);
  letter-spacing: 0.08em;
  color: var(--mist);
}

.page-about .ab-fact dd {
  margin: 0.2rem 0 0;
  font-size: var(--fs-26);
  line-height: 1.2;
  color: var(--gold);
}

/* ---------- 章节索引卡 ---------- */
.page-about .ab-index {
  border: 1px solid var(--steel);
  border-left: 2px solid var(--gold);
  background: linear-gradient(180deg, rgba(12, 44, 46, 0.8), rgba(10, 20, 48, 0.94));
  padding: 1.15rem 1.1rem 1.25rem;
  box-shadow: var(--shadow-lift);
}

.page-about .ab-index-title {
  margin: 0 0 0.75rem;
  font-size: var(--fs-12);
  letter-spacing: 0.18em;
  color: var(--gold);
}

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

.page-about .ab-index a {
  display: flex;
  align-items: baseline;
  gap: 0.7rem;
  padding: 0.55rem 0.15rem;
  font-size: var(--fs-14);
  color: var(--paper);
  text-decoration: none;
  border-bottom: 1px solid var(--ab-steel-soft);
  transition: color var(--dur) var(--ease), padding-left var(--dur) var(--ease);
}

.page-about .ab-index li:last-child a {
  border-bottom: 0;
}

.page-about .ab-index a:hover,
.page-about .ab-index a:focus-visible {
  color: var(--amber);
  padding-left: 0.35rem;
}

.page-about .ab-index .num {
  font-size: var(--fs-12);
  color: var(--gold);
}

/* ---------- 章节通用 ---------- */
.page-about .ab-sec {
  position: relative;
  padding-block: clamp(2.75rem, 8vw, 5.25rem);
}

.page-about .ab-sec-head {
  display: flex;
  align-items: baseline;
  gap: 0.9rem;
  padding-bottom: 0.85rem;
  margin-bottom: 1.75rem;
  border-bottom: 1px solid var(--steel);
}

.page-about .ab-sec-num {
  font-size: var(--fs-34);
  line-height: 1;
  color: var(--gold);
  flex: none;
}

.page-about .ab-sec-title {
  font-size: clamp(1.35rem, 4.6vw, 2.1rem);
  font-weight: 900;
  line-height: 1.22;
  margin: 0;
}

.page-about .ab-fig {
  border: 1px solid var(--steel);
  background: var(--ink-deep);
  padding: 0.4rem;
  margin: 0;
}

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

.page-about .ab-fig-cap {
  margin: 0.6rem 0.15rem 0.15rem;
  font-size: var(--fs-12);
  line-height: 1.6;
  color: var(--mist);
}

/* ---------- 01 起点 ---------- */
.page-about .ab-sec--origin {
  background:
    linear-gradient(180deg, var(--ink) 0%, var(--ink-deep) 100%);
}

.page-about .ab-origin-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.75rem;
}

.page-about .ab-origin-text p {
  max-width: 38em;
}

.page-about .ab-origin-list {
  list-style: none;
  margin: 1.5rem 0 0;
  padding: 0;
  display: grid;
  gap: 1rem;
}

.page-about .ab-origin-list li {
  position: relative;
  padding-left: 1.4rem;
  font-size: var(--fs-14);
  line-height: 1.8;
  color: var(--mist);
}

.page-about .ab-origin-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.85rem;
  width: 0.75rem;
  height: 1px;
  background: var(--gold);
}

.page-about .ab-origin-list strong {
  display: block;
  color: var(--paper);
  font-size: var(--fs-16);
  letter-spacing: -0.01em;
  margin-bottom: 0.1rem;
}

/* ---------- 02 时间线 ---------- */
.page-about .ab-sec--timeline {
  background:
    radial-gradient(60% 50% at 100% 0%, rgba(12, 44, 46, 0.9), transparent 70%),
    var(--teal);
  border-block: 1px solid var(--steel);
}

.page-about .ab-tl {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 2rem;
}

.page-about .ab-tl-fig {
  max-width: 22rem;
}

.page-about .ab-tl-jump {
  list-style: none;
  margin: 1.1rem 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
}

.page-about .ab-tl-jump a {
  display: inline-flex;
  align-items: baseline;
  gap: 0.4rem;
  padding: 0.3rem 0.65rem;
  font-size: var(--fs-12);
  color: var(--paper);
  text-decoration: none;
  border: 1px solid var(--ab-steel-soft);
  border-radius: var(--radius);
  background: rgba(10, 20, 48, 0.55);
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

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

.page-about .ab-tl-jump .num {
  color: var(--gold);
}

.page-about .ab-tl-list {
  list-style: none;
  margin: 0;
  padding: 0 0 0 1.5rem;
  border-left: 1px solid var(--gold-line);
}

.page-about .ab-tl-item {
  position: relative;
  padding-bottom: 1.85rem;
  scroll-margin-top: 1.5rem;
}

.page-about .ab-tl-item:last-child {
  padding-bottom: 0;
}

.page-about .ab-tl-item::before {
  content: "";
  position: absolute;
  left: -1.5rem;
  top: 0.6rem;
  width: 9px;
  height: 9px;
  margin-left: -4.5px;
  border-radius: 50%;
  border: 1px solid var(--gold);
  background: var(--teal);
  transform: translateX(-50%);
  transition: background var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .ab-tl-item:hover::before,
.page-about .ab-tl-item:target::before {
  background: var(--gold);
  box-shadow: 0 0 0 5px var(--ab-gold-soft);
}

.page-about .ab-tl-era {
  margin: 0;
  font-size: var(--fs-12);
  letter-spacing: 0.12em;
  color: var(--gold);
}

.page-about .ab-tl-title {
  font-size: var(--fs-20);
  font-weight: 900;
  margin: 0.2rem 0 0.4rem;
}

.page-about .ab-tl-body {
  max-width: 36em;
  border-left: 1px solid var(--ab-steel-soft);
  padding-left: 0.9rem;
}

.page-about .ab-tl-body p {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.85;
}

/* ---------- 留白呼吸区 ---------- */
.page-about .ab-quiet {
  padding-block: clamp(2.75rem, 10vw, 6rem);
  background: var(--wine);
  border-block: 1px solid var(--steel);
}

.page-about .ab-quiet-rule {
  margin: 0 auto 1.1rem;
  max-width: 5rem;
}

.page-about .ab-quiet-line {
  margin: 0;
  text-align: center;
  font-size: clamp(1.05rem, 3.4vw, 1.6rem);
  font-weight: 900;
  letter-spacing: -0.01em;
  color: var(--paper);
}

/* ---------- 03 团队 ---------- */
.page-about .ab-sec--teams {
  background:
    radial-gradient(70% 60% at 0% 100%, rgba(26, 23, 64, 0.95), transparent 70%),
    var(--ink);
}

.page-about .ab-teams-lede {
  max-width: 34em;
  font-size: var(--fs-14);
  margin-bottom: 1.5rem;
}

.page-about .ab-teams {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1rem;
}

.page-about .ab-team {
  padding: 1.15rem 1.05rem 1.25rem;
  border: 1px solid var(--steel);
  border-top: 2px solid var(--gold);
  border-radius: var(--radius);
  background: linear-gradient(180deg, rgba(12, 44, 46, 0.55), rgba(10, 20, 48, 0.9));
  box-shadow: var(--shadow-lift);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

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

.page-about .ab-team-tag {
  margin: 0;
  font-size: var(--fs-12);
  letter-spacing: 0.14em;
  color: var(--gold);
}

.page-about .ab-team-name {
  font-size: var(--fs-20);
  font-weight: 900;
  margin: 0.3rem 0 0.4rem;
}

.page-about .ab-team-lead {
  margin: 0;
  font-size: var(--fs-14);
  color: var(--mist);
}

.page-about .ab-team-more {
  list-style: none;
  margin: 0.8rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.45rem;
}

.page-about .ab-team-more li {
  position: relative;
  padding-left: 1rem;
  font-size: var(--fs-14);
  line-height: 1.75;
  color: var(--mist);
}

.page-about .ab-team-more li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.75rem;
  width: 0.5rem;
  height: 1px;
  background: var(--jade);
}

/* ---------- 04 三步 ---------- */
.page-about .ab-sec--review {
  background: var(--ink-deep);
  border-block: 1px solid var(--steel);
}

.page-about .ab-review-lede {
  max-width: 34em;
  font-size: var(--fs-14);
  margin-bottom: 1.5rem;
}

.page-about .ab-steps {
  list-style: none;
  margin: 0 0 1.75rem;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1rem;
}

.page-about .ab-step {
  position: relative;
  padding: 1.1rem 1.05rem 1.2rem;
  border: 1px solid var(--steel);
  border-radius: var(--radius);
  background: rgba(12, 44, 46, 0.35);
}

.page-about .ab-step-num {
  margin: 0;
  font-size: var(--fs-20);
  color: var(--gold);
  line-height: 1.2;
}

.page-about .ab-step-title {
  font-size: var(--fs-16);
  font-weight: 900;
  margin: 0.2rem 0 0.15rem;
}

.page-about .ab-step-owner {
  margin: 0 0 0.55rem;
  font-size: var(--fs-12);
  letter-spacing: 0.1em;
  color: var(--jade);
}

.page-about .ab-step-body {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.8;
}

.page-about .ab-review-fig {
  max-width: 100%;
}

/* ---------- 05 合作 ---------- */
.page-about .ab-sec--partners {
  background:
    radial-gradient(70% 70% at 90% 10%, rgba(12, 44, 46, 0.9), transparent 68%),
    var(--ink);
}

.page-about .ab-eco {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.5rem;
}

.page-about .ab-eco-text p {
  max-width: 36em;
}

.page-about .ab-eco-link {
  font-size: var(--fs-14);
}

.page-about .ab-eco-link a {
  color: var(--gold);
  text-decoration: none;
  border-bottom: 1px solid var(--gold-line);
}

.page-about .ab-eco-link a:hover,
.page-about .ab-eco-link a:focus-visible {
  color: var(--amber);
}

.page-about .ab-eco-side {
  display: grid;
  gap: 0.9rem;
}

.page-about .ab-award {
  padding: 1.05rem 1rem 1.15rem;
  background: var(--wine);
  border: 1px solid rgba(216, 169, 75, 0.28);
  border-left: 3px solid var(--gold);
  border-radius: var(--radius);
}

.page-about .ab-award-label {
  margin: 0 0 0.4rem;
  font-size: var(--fs-12);
  letter-spacing: 0.18em;
  color: var(--gold);
}

.page-about .ab-award-text {
  margin: 0;
  font-size: var(--fs-16);
  font-weight: 900;
  line-height: 1.6;
  color: var(--paper);
}

.page-about .ab-eco-note {
  padding: 1.05rem 1rem 1.15rem;
  border: 1px solid var(--steel);
  border-radius: var(--radius);
  background: rgba(10, 20, 48, 0.7);
}

.page-about .ab-eco-note-title {
  margin: 0 0 0.45rem;
  font-size: var(--fs-12);
  letter-spacing: 0.16em;
  color: var(--mist);
}

.page-about .ab-eco-note p:last-child {
  margin: 0;
  font-size: var(--fs-14);
}

/* ---------- 06 地点 ---------- */
.page-about .ab-sec--place {
  background: var(--ink-deep);
  border-top: 1px solid var(--steel);
}

.page-about .ab-place {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.25rem;
}

.page-about .ab-place-text p {
  max-width: 36em;
  font-size: var(--fs-14);
}

.page-about .ab-place-text a {
  color: var(--gold);
  text-decoration: none;
  border-bottom: 1px solid var(--gold-line);
}

.page-about .ab-place-links {
  display: grid;
  gap: 0.7rem;
}

.page-about .ab-place-link {
  display: grid;
  gap: 0.2rem;
  padding: 0.9rem 1rem;
  text-decoration: none;
  border: 1px solid var(--steel);
  border-left: 2px solid var(--jade);
  border-radius: var(--radius);
  background: rgba(12, 44, 46, 0.35);
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .ab-place-link:hover,
.page-about .ab-place-link:focus-visible {
  border-color: var(--gold-line);
  border-left-color: var(--amber);
  background: rgba(12, 44, 46, 0.6);
}

.page-about .ab-place-link-title {
  font-size: var(--fs-14);
  font-weight: 900;
  color: var(--paper);
}

.page-about .ab-place-link-note {
  font-size: var(--fs-12);
  line-height: 1.7;
  color: var(--mist);
}

/* ---------- 小屏优先的桌面增强 ---------- */
@media (min-width: 640px) {
  .page-about .ab-hero-actions {
    grid-template-columns: repeat(2, minmax(0, max-content));
    gap: 0.75rem;
  }

  .page-about .ab-quiet-line {
    letter-spacing: 0.01em;
  }

  .page-about .ab-steps {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1.25rem;
  }

  .page-about .ab-step + .ab-step::after {
    content: "";
    position: absolute;
    top: 1.9rem;
    left: -1.25rem;
    width: 1.25rem;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--gold));
  }
}

@media (min-width: 760px) {
  .page-about .ab-teams {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    gap: 1.25rem;
  }

  .page-about .ab-team:nth-child(1) {
    grid-column: 1 / 7;
    margin-top: 0;
  }

  .page-about .ab-team:nth-child(2) {
    grid-column: 8 / 13;
    margin-top: 2.25rem;
  }

  .page-about .ab-team:nth-child(3) {
    grid-column: 2 / 8;
    margin-top: 1.25rem;
  }

  .page-about .ab-team:nth-child(4) {
    grid-column: 9 / 13;
    margin-top: 3.5rem;
  }

  .page-about .ab-eco {
    grid-template-columns: minmax(0, 6fr) minmax(0, 5fr);
    gap: clamp(1.5rem, 4vw, 3rem);
    align-items: start;
  }

  .page-about .ab-place {
    grid-template-columns: minmax(0, 6fr) minmax(0, 5fr);
    gap: clamp(1.5rem, 4vw, 3rem);
    align-items: start;
  }
}

@media (min-width: 900px) {
  .page-about .ab-hero-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: clamp(1.75rem, 4vw, 3.5rem);
    align-items: start;
  }

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

  .page-about .ab-origin-grid {
    grid-template-columns: minmax(0, 6fr) minmax(0, 5fr);
    gap: clamp(1.75rem, 4vw, 3.25rem);
    align-items: start;
  }

  .page-about .ab-tl {
    grid-template-columns: minmax(0, 4fr) minmax(0, 7fr);
    gap: clamp(1.75rem, 4vw, 3.5rem);
  }

  .page-about .ab-tl-left {
    position: sticky;
    top: 1.5rem;
    align-self: start;
  }

  .page-about .ab-tl-item:nth-child(even) .ab-tl-body {
    margin-left: 1.75rem;
  }
}

@media (min-width: 760px) and (hover: hover) {
  .page-about .ab-team-more {
    max-height: 0;
    opacity: 0;
    overflow: hidden;
    margin-top: 0;
    transition: max-height var(--dur) var(--ease), opacity var(--dur) var(--ease),
      margin-top var(--dur) var(--ease);
  }

  .page-about .ab-team:hover .ab-team-more,
  .page-about .ab-team:focus .ab-team-more,
  .page-about .ab-team:focus-within .ab-team-more {
    max-height: 14rem;
    opacity: 1;
    margin-top: 0.8rem;
  }
}