.page-about {
  --ab-gap: clamp(16px, 2.4vw, 28px);
  --ab-band-y: clamp(48px, 7.4vw, 96px);
  --ab-card-bg: linear-gradient(155deg, rgba(16, 34, 74, .92), rgba(10, 21, 51, .96));
  color: var(--text-hi);
  font-family: var(--font-body);
  background:
    radial-gradient(1100px 620px at 92% -6%, rgba(23, 48, 95, .68), transparent 66%),
    radial-gradient(760px 520px at 4% 44%, rgba(42, 66, 114, .34), transparent 70%),
    linear-gradient(180deg, var(--ink-abyss) 0%, var(--navy-900) 44%, var(--ink-abyss) 100%);
  padding-bottom: clamp(40px, 6vw, 80px);
}

.page-about .ab-band {
  padding: var(--ab-band-y) 0;
}

.page-about .ab-band--alt {
  background: linear-gradient(180deg, rgba(10, 21, 51, 0), rgba(16, 34, 74, .5) 26%, rgba(16, 34, 74, .5) 74%, rgba(10, 21, 51, 0));
}

.page-about .ab-narrow {
  max-width: 880px;
}

/* ---------- 分节标题 ---------- */
.page-about .section-head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin: 0 0 clamp(20px, 3vw, 34px);
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line-blue);
}

.page-about .section-head__index {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .12em;
  color: var(--warm-orange);
  flex: 0 0 auto;
}

.page-about .section-head__title {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(22px, 2.8vw, 31px);
  line-height: 1.24;
  color: var(--text-hi);
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  padding: clamp(28px, 5vw, 60px) 0 clamp(36px, 6vw, 72px);
}

.page-about .ab-hero__copy {
  max-width: 900px;
  margin-top: clamp(24px, 4vw, 46px);
}

.page-about .ab-hero__kicker {
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--neon-lime);
}

.page-about .ab-hero h1 {
  margin: 0 0 22px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(30px, 5.6vw, 54px);
  line-height: 1.12;
  letter-spacing: -.01em;
  color: var(--text-hi);
}

.page-about .ab-hero__lede {
  margin: 0;
  max-width: 66ch;
  font-size: clamp(15.5px, 1.15vw, 18px);
  line-height: 1.82;
  color: var(--text-mid);
}

.page-about .ab-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(24px, 3.4vw, 34px);
}

/* ---------- 数字墙 ---------- */
.page-about .stat-wall {
  list-style: none;
  margin: clamp(36px, 5.6vw, 68px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line-blue);
  border: 1px solid var(--line-blue);
  border-radius: var(--radius-l);
  overflow: hidden;
  box-shadow: var(--shadow-card);
}

.page-about .stat {
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  gap: 10px;
  min-height: 132px;
  padding: clamp(18px, 2.8vw, 30px) clamp(14px, 2.2vw, 26px);
  background: var(--ab-card-bg);
}

.page-about .stat__value {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(36px, 5.6vw, 62px);
  line-height: 1;
  letter-spacing: -.03em;
  color: var(--text-hi);
}

.page-about .stat__unit {
  font-size: .34em;
  margin-left: 5px;
  font-weight: 500;
  color: var(--neon-lime);
}

.page-about .stat__label {
  font-size: 13px;
  line-height: 1.5;
  letter-spacing: .04em;
  color: var(--text-mid);
}

.page-about .stat--accent .stat__value {
  color: var(--warm-orange);
}

/* ---------- 时间轴 ---------- */
.page-about .ab-tl-figure {
  margin: 0 0 clamp(28px, 4vw, 46px);
}

.page-about .ab-tl-figure figcaption,
.page-about .ab-cover__art figcaption,
.page-about .ab-team__art figcaption {
  margin-top: 12px;
  font-size: 13px;
  line-height: 1.68;
  color: var(--text-mid);
}

.page-about .tl-track {
  display: grid;
  gap: 12px;
  position: relative;
}

.page-about .tl-node {
  position: relative;
  padding: 16px 18px 16px 44px;
  background: var(--navy-800);
  border: 1px solid var(--line-blue);
  border-radius: var(--radius-m);
}

.page-about .tl-node__head {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 12px;
  cursor: pointer;
  list-style: none;
  outline-offset: 4px;
}

.page-about .tl-node__head::-webkit-details-marker {
  display: none;
}

.page-about .tl-node__head::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--neon-lime);
}

.page-about .tl-node[open] .tl-node__head::after {
  content: "−";
  color: var(--warm-orange);
}

.page-about .tl-node__dot {
  position: absolute;
  left: 18px;
  top: 22px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--neon-lime);
  box-shadow: 0 0 0 4px rgba(185, 255, 60, .14);
}

.page-about .tl-node__stage {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 16.5px;
  color: var(--text-hi);
}

.page-about .tl-node__ver {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--text-mid);
}

.page-about .tl-node__body {
  margin: 12px 0 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--text-mid);
}

.page-about .tl-node--now {
  border-color: rgba(255, 122, 47, .58);
  background: linear-gradient(150deg, rgba(255, 122, 47, .14), var(--navy-800) 62%);
}

.page-about .tl-node--now .tl-node__dot {
  background: var(--warm-orange);
  box-shadow: 0 0 0 5px rgba(255, 122, 47, .2);
}

.page-about .tl-node--now .tl-node__ver {
  color: var(--warm-orange);
}

/* ---------- 覆盖与规模 ---------- */
.page-about .ab-scale-row {
  list-style: none;
  margin: 0 0 clamp(30px, 4.6vw, 52px);
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0;
  border-top: 1px solid var(--line-blue);
}

.page-about .ab-scale {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 18px 4px 20px;
  border-bottom: 1px solid var(--line-blue);
}

.page-about .ab-scale__num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(28px, 3.6vw, 42px);
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--neon-lime);
}

.page-about .ab-scale__plus {
  font-size: .58em;
  color: var(--cyan-data);
}

.page-about .ab-scale__label {
  font-size: 13px;
  letter-spacing: .04em;
  color: var(--text-mid);
}

.page-about .ab-cover {
  align-items: start;
}

.page-about .ab-lede {
  margin-top: 0;
  font-size: clamp(16px, 1.15vw, 17.5px);
  color: var(--text-hi);
}

.page-about .ab-cover__copy p {
  line-height: 1.82;
  color: var(--text-mid);
}

.page-about .ab-ring-wrap {
  display: flex;
  align-items: center;
  gap: 18px;
  margin: clamp(24px, 3.4vw, 36px) 0 0;
  padding: 18px 20px;
  border: 1px solid var(--line-blue);
  border-radius: var(--radius-m);
  background: rgba(16, 34, 74, .42);
}

.page-about .ab-ring {
  width: 104px;
  height: 104px;
  flex: 0 0 auto;
}

.page-about .ab-ring__track {
  stroke: var(--line-blue);
}

.page-about .ab-ring__arcs {
  stroke: var(--neon-lime);
}

.page-about .ab-ring__core {
  stroke: var(--cyan-data);
  opacity: .55;
}

.page-about .ab-ring-wrap figcaption {
  margin: 0;
  font-size: 13px;
  line-height: 1.72;
  color: var(--text-mid);
}

.page-about .ab-cover__art {
  margin: 0;
}

/* ---------- 数据来源 ---------- */
.page-about .ab-source p {
  font-size: clamp(15.5px, 1.1vw, 17px);
  line-height: 1.86;
  color: var(--text-mid);
}

.page-about .ab-source a {
  color: var(--neon-lime);
}

.page-about .ab-fold {
  margin-top: clamp(24px, 3.4vw, 36px);
  border: 1px solid var(--line-blue);
  border-left: 3px solid var(--cyan-data);
  border-radius: var(--radius-m);
  background: rgba(16, 34, 74, .5);
  padding: 16px 20px;
}

.page-about .ab-fold summary {
  cursor: pointer;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 16px;
  color: var(--text-hi);
  list-style: none;
}

.page-about .ab-fold summary::-webkit-details-marker {
  display: none;
}

.page-about .ab-fold summary::before {
  content: "›";
  display: inline-block;
  margin-right: 10px;
  font-family: var(--font-mono);
  color: var(--neon-lime);
  transition: transform .2s ease;
}

.page-about .ab-fold[open] summary::before {
  transform: rotate(90deg);
}

.page-about .ab-fold p {
  margin: 12px 0 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--text-mid);
}

.page-about .ab-fold a {
  color: var(--neon-lime);
}

/* ---------- 团队 ---------- */
.page-about .ab-team {
  align-items: start;
}

.page-about .ab-team__text p {
  font-size: 15.5px;
  line-height: 1.86;
  color: var(--text-mid);
}

.page-about .ab-team__art {
  margin: 0;
}

.page-about .ab-eco {
  margin-top: clamp(34px, 5vw, 58px);
}

.page-about .ab-eco__bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 22px;
}

.page-about .ab-eco__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .ab-eco__item {
  padding: 18px 20px;
  border: 1px solid var(--line-blue);
  border-left: 3px solid var(--neon-lime);
  border-radius: var(--radius-m);
  background: var(--ab-card-bg);
}

.page-about .ab-eco__item:nth-child(3n+2) {
  border-left-color: var(--cyan-data);
}

.page-about .ab-eco__item:nth-child(3n+3) {
  border-left-color: var(--warm-orange);
}

.page-about .ab-eco__tag {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--neon-lime);
}

.page-about .ab-eco__item p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--text-mid);
}

/* ---------- 年度承诺 ---------- */
.page-about .ab-commit p {
  font-size: clamp(15.5px, 1.1vw, 17px);
  line-height: 1.86;
  color: var(--text-mid);
}

/* ---------- 收尾 ---------- */
.page-about .ab-band--close {
  padding-top: clamp(30px, 4vw, 46px);
}

.page-about .ab-close {
  padding: clamp(26px, 4vw, 44px);
  border: 1px solid var(--line-blue);
  border-radius: var(--radius-l);
  background:
    linear-gradient(120deg, rgba(185, 255, 60, .08), transparent 42%),
    linear-gradient(160deg, rgba(16, 34, 74, .9), rgba(6, 11, 28, .96));
  box-shadow: var(--shadow-card);
}

.page-about .ab-close h2 {
  margin: 0 0 12px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(21px, 2.6vw, 29px);
  line-height: 1.28;
  color: var(--text-hi);
}

.page-about .ab-close p {
  margin: 0;
  max-width: 56ch;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--text-mid);
}

.page-about .ab-close__links {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px 22px;
  margin-top: clamp(20px, 3vw, 30px);
}

.page-about .ab-close__link {
  font-size: 14.5px;
  color: var(--text-hi);
  text-decoration: underline;
  text-decoration-color: rgba(185, 255, 60, .55);
  text-underline-offset: 4px;
}

.page-about .ab-close__link:hover {
  color: var(--neon-lime);
}

@media (min-width: 700px) {
  .page-about .ab-scale-row {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .ab-scale {
    padding: 22px 18px 24px;
    border-right: 1px solid var(--line-blue);
  }

  .page-about .ab-scale:nth-child(3n) {
    border-right: 0;
  }

  .page-about .ab-eco__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 860px) {
  .page-about .stat-wall {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .ab-scale-row {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }

  .page-about .ab-scale:nth-child(3n) {
    border-right: 1px solid var(--line-blue);
  }

  .page-about .ab-scale:last-child {
    border-right: 0;
  }
}

@media (min-width: 900px) {
  .page-about .tl-track {
    grid-template-columns: repeat(5, minmax(0, 1fr));
    gap: 18px;
    padding-top: 40px;
    align-items: start;
  }

  .page-about .tl-track::before {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    top: 14px;
    height: 1px;
    background: linear-gradient(90deg, rgba(42, 66, 114, .95), rgba(185, 255, 60, .7) 56%, rgba(255, 122, 47, .9));
  }

  .page-about .tl-node {
    padding: 0;
    background: transparent;
    border: 0;
  }

  .page-about .tl-node__head {
    display: block;
    padding-right: 18px;
  }

  .page-about .tl-node__head::after {
    position: absolute;
    right: 0;
    top: 0;
  }

  .page-about .tl-node__dot {
    left: 0;
    top: -30px;
  }

  .page-about .tl-node__stage {
    display: block;
    font-size: 15.5px;
    margin-bottom: 6px;
  }

  .page-about .tl-node__ver {
    display: block;
  }

  .page-about .tl-node__body {
    margin-top: 14px;
    font-size: 13.8px;
    line-height: 1.72;
  }

  .page-about .tl-node--now {
    padding: 16px 16px 18px;
    border: 1px solid rgba(255, 122, 47, .38);
    background: linear-gradient(180deg, rgba(255, 122, 47, .12), rgba(255, 122, 47, 0));
  }

  .page-about .tl-node--now .tl-node__dot {
    top: -46px;
    left: -1px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-fold summary::before {
    transition: none;
  }
}