.page-about {
  --ab-rule: rgba(30, 58, 82, 0.72);
  --ab-rule-strong: rgba(79, 216, 232, 0.32);
  --ab-panel: rgba(11, 23, 38, 0.72);
  --ab-rail: clamp(0px, 4vw, 72px);
  position: relative;
  color: var(--fog);
  padding-bottom: calc(var(--service-h) + 32px);
  background:
    radial-gradient(120% 60% at 100% 0%, rgba(79, 216, 232, 0.07), transparent 60%),
    var(--ink-900);
  overflow-x: clip;
}

.page-about img {
  max-width: 100%;
  height: auto;
  display: block;
}

.page-about .figure {
  margin: 0;
  border: 1px solid var(--ab-rule);
  border-radius: var(--r-m);
  overflow: hidden;
  background: var(--ink-800);
}

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

.page-about .figure-cap {
  font-family: var(--font-num);
  letter-spacing: 0.04em;
}

/* ---------- 首屏 ---------- */

.page-about .ab-hero {
  padding: 22px 0 40px;
}

.page-about .ab-hero .breadcrumb {
  margin-bottom: 30px;
}

.page-about .ab-hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
}

.page-about .ab-hero-copy {
  min-width: 0;
}

.page-about .ab-hero h1 {
  font-family: var(--font-cn);
  font-weight: 900;
  font-size: clamp(32px, 8.4vw, 68px);
  line-height: 1.08;
  letter-spacing: 0.025em;
  margin: 10px 0 20px;
  color: var(--fog);
}

.page-about .ab-hero-lede {
  font-size: 16px;
  line-height: 1.85;
  color: var(--glacier);
  max-width: 36ch;
  margin: 0;
}

.page-about .ab-hero-stats {
  list-style: none;
  margin: 30px 0 0;
  padding: 20px 0 0;
  border-top: 1px solid var(--ab-rule);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px 20px;
}

.page-about .ab-stat-num {
  display: block;
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: 28px;
  font-weight: 700;
  line-height: 1.1;
  color: var(--cyan);
}

.page-about .ab-stat-num em {
  font-style: normal;
  font-size: 15px;
  color: var(--glacier);
  margin-left: 2px;
}

.page-about .ab-stat-label {
  display: block;
  margin-top: 4px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--glacier);
}

/* ---------- 起点 / 现在 ---------- */

.page-about .ab-compare {
  padding: 44px 0;
  border-top: 1px solid var(--ab-rule);
  border-bottom: 1px solid var(--ab-rule);
}

.page-about .ab-compare-title {
  font-size: clamp(18px, 3.4vw, 24px);
  font-weight: 700;
  color: var(--glacier);
  margin: 0 0 22px;
  letter-spacing: 0.04em;
}

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

.page-about .ab-compare-col {
  padding: 22px 0;
}

.page-about .ab-compare-col--past {
  border-bottom: 1px solid var(--ab-rule);
}

.page-about .ab-compare-tag {
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--gold);
  margin: 0 0 12px;
}

.page-about .ab-compare-big {
  font-weight: 800;
  line-height: 1.35;
  letter-spacing: 0.02em;
  margin: 0 0 12px;
}

.page-about .ab-compare-col--past .ab-compare-big {
  font-size: clamp(19px, 2.6vw, 24px);
  color: var(--glacier);
  font-weight: 600;
}

.page-about .ab-compare-col--now .ab-compare-big {
  font-size: clamp(25px, 4.6vw, 42px);
  color: var(--fog);
}

.page-about .ab-compare-text {
  font-size: 15px;
  line-height: 1.85;
  color: var(--glacier);
  margin: 0;
  max-width: 38ch;
}

/* ---------- 章节通用 ---------- */

.page-about .ab-chapter {
  padding: 56px 0 8px;
}

.page-about .ab-chapter-head {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 26px;
}

.page-about .ab-chapter-head .sec-index {
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--gold);
  flex: 0 0 auto;
  padding-top: 4px;
}

.page-about .ab-chapter-rule {
  flex: 0 0 22px;
  height: 1px;
  background: var(--ab-rule-strong);
}

.page-about .ab-chapter-head h2 {
  font-size: clamp(23px, 4.4vw, 36px);
  font-weight: 800;
  letter-spacing: 0.03em;
  line-height: 1.2;
  margin: 0;
  color: var(--fog);
}

.page-about .ab-lede {
  font-size: 15px;
  line-height: 1.85;
  color: var(--glacier);
  max-width: 56ch;
  margin: 0 0 26px;
}

/* ---------- 三件事 ---------- */

.page-about .ab-works {
  display: grid;
  border-top: 1px solid var(--ab-rule);
}

.page-about .ab-work {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 14px;
  padding: 22px 0;
  border-bottom: 1px solid var(--ab-rule);
}

.page-about .ab-work-no {
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--gold);
  padding-top: 5px;
}

.page-about .ab-work-body h3 {
  font-size: 20px;
  font-weight: 800;
  letter-spacing: 0.02em;
  color: var(--cyan);
  margin: 0 0 10px;
}

.page-about .ab-work-body p {
  font-size: 15px;
  line-height: 1.85;
  color: var(--fog);
  margin: 0 0 8px;
  max-width: 54ch;
}

.page-about .ab-work-note {
  font-size: 13px;
  line-height: 1.6;
  color: var(--glacier);
  padding-left: 12px;
  border-left: 2px solid var(--ab-rule-strong);
}

/* ---------- 栏目五类 ---------- */

.page-about .ab-cats {
  border-top: 1px solid var(--ab-rule);
}

.page-about .ab-cat {
  display: grid;
  gap: 10px;
  padding: 20px 0;
  border-bottom: 1px solid var(--ab-rule);
}

.page-about .ab-cat-head {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .ab-cat-no {
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: 11px;
  color: var(--gold);
  letter-spacing: 0.1em;
}

.page-about .ab-cat-head h3 {
  font-size: 19px;
  font-weight: 800;
  letter-spacing: 0.02em;
  color: var(--fog);
  margin: 0;
}

.page-about .ab-cat-count {
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--cyan);
  border: 1px solid var(--ab-rule-strong);
  border-radius: var(--r-pill);
  padding: 2px 10px;
}

.page-about .ab-cat p {
  font-size: 15px;
  line-height: 1.85;
  color: var(--glacier);
  margin: 0;
  max-width: 60ch;
}

/* ---------- 记录 ---------- */

.page-about .ab-rec-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
}

.page-about .ab-rec-main p {
  font-size: 15px;
  line-height: 1.9;
  color: var(--fog);
  margin: 0 0 14px;
  max-width: 46ch;
}

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

.page-about .ab-rec-aside {
  padding: 20px 20px 18px;
  border-radius: var(--r-m);
  background: var(--ab-panel);
  border: 1px solid var(--ab-rule);
}

.page-about .ab-rec-aside h3 {
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--gold);
  margin: 0 0 14px;
  text-transform: uppercase;
}

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

.page-about .ab-rec-aside li {
  font-size: 14px;
  line-height: 1.7;
  color: var(--glacier);
  padding-left: 12px;
  border-left: 1px solid var(--ab-rule);
}

.page-about .ab-rec-aside strong {
  color: var(--cyan);
  font-weight: 700;
  margin-right: 6px;
}

.page-about .ab-chain {
  margin-top: 28px;
  padding-top: 22px;
  border-top: 1px dashed var(--ab-rule);
}

.page-about .ab-chain-cap {
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--glacier);
  margin: 0 0 16px;
}

.page-about .ab-chain-list {
  list-style: none;
  counter-reset: chain;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 10px;
}

.page-about .ab-chain-list li {
  position: relative;
  counter-increment: chain;
  padding: 12px 14px 12px 40px;
  border: 1px solid var(--ab-rule);
  border-radius: var(--r-s);
  background: rgba(18, 37, 58, 0.45);
}

.page-about .ab-chain-list li::before {
  content: "0" counter(chain);
  position: absolute;
  left: 14px;
  top: 13px;
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--gold);
}

.page-about .ab-chain-k {
  display: block;
  font-size: 14px;
  font-weight: 700;
  color: var(--fog);
  margin-bottom: 3px;
}

.page-about .ab-chain-v {
  display: block;
  font-size: 13px;
  line-height: 1.6;
  color: var(--glacier);
}

/* ---------- 团队 ---------- */

.page-about .ab-team-figure {
  margin-bottom: 28px;
}

.page-about .ab-team-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 32px;
}

.page-about .ab-team-num {
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: clamp(52px, 13vw, 84px);
  font-weight: 700;
  line-height: 0.9;
  color: var(--cyan);
  margin: 0;
}

.page-about .ab-team-cap {
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--glacier);
  margin: 10px 0 18px;
}

.page-about .ab-team-split {
  list-style: none;
  margin: 0 0 18px;
  padding: 0;
  display: grid;
  gap: 8px;
}

.page-about .ab-team-split li {
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-size: 14px;
  color: var(--fog);
  padding-bottom: 8px;
  border-bottom: 1px solid var(--ab-rule);
}

.page-about .ab-team-split span {
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: 18px;
  font-weight: 700;
  color: var(--gold);
  min-width: 34px;
}

.page-about .ab-team-text {
  font-size: 14px;
  line-height: 1.85;
  color: var(--glacier);
  margin: 0;
}

.page-about .ab-flow h3 {
  font-size: 18px;
  font-weight: 800;
  letter-spacing: 0.02em;
  color: var(--fog);
  margin: 0 0 18px;
}

.page-about .ab-flow-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 18px;
}

.page-about .ab-flow-list li {
  display: grid;
  grid-template-columns: 32px minmax(0, 1fr);
  gap: 14px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--ab-rule);
}

.page-about .ab-flow-list li:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .ab-flow-no {
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: 12px;
  font-weight: 700;
  color: var(--ink-900);
  background: var(--gold);
  border-radius: 50%;
  width: 26px;
  height: 26px;
  display: grid;
  place-items: center;
}

.page-about .ab-flow-list h4 {
  font-size: 16px;
  font-weight: 700;
  color: var(--cyan);
  margin: 0 0 6px;
}

.page-about .ab-flow-list p {
  font-size: 14px;
  line-height: 1.8;
  color: var(--glacier);
  margin: 0;
}

.page-about .ab-flow-note {
  font-size: 13px;
  line-height: 1.75;
  color: var(--glacier);
  margin: 20px 0 0;
  padding: 12px 14px;
  border-left: 2px solid var(--coral);
  background: rgba(255, 107, 74, 0.06);
}

/* ---------- 合作 ---------- */

.page-about .ab-partner-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 24px;
}

.page-about .ab-partner-ways {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 18px;
}

.page-about .ab-partner-ways li {
  padding-left: 14px;
  border-left: 2px solid var(--ab-rule-strong);
}

.page-about .ab-partner-tag {
  display: inline-block;
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--coral);
  margin-bottom: 8px;
}

.page-about .ab-partner-ways p {
  font-size: 14px;
  line-height: 1.85;
  color: var(--glacier);
  margin: 0;
}

.page-about .ab-partner-gain {
  padding: 22px 20px;
  border-radius: var(--r-m);
  background: var(--ab-panel);
  border: 1px solid var(--ab-rule);
}

.page-about .ab-partner-gain h3 {
  font-size: 16px;
  font-weight: 800;
  color: var(--cyan);
  margin: 0 0 14px;
  letter-spacing: 0.02em;
}

.page-about .ab-partner-gain p {
  font-size: 14px;
  line-height: 1.8;
  color: var(--glacier);
  margin: 0 0 12px;
}

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

/* ---------- 时间线 ---------- */

.page-about .ab-tl-banner {
  position: relative;
  border: 1px solid var(--ab-rule);
  border-radius: var(--r-m);
  overflow: hidden;
  margin-bottom: 22px;
}

.page-about .ab-tl-banner img {
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .ab-tl-banner p {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  margin: 0;
  padding: 40px 18px 16px;
  font-size: clamp(17px, 3vw, 24px);
  font-weight: 800;
  letter-spacing: 0.04em;
  color: var(--fog);
  background: linear-gradient(to top, rgba(5, 11, 20, 0.94), rgba(5, 11, 20, 0));
}

.page-about .ab-tl-jump {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 26px;
}

.page-about .ab-tl-jump a {
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-decoration: none;
  color: var(--cyan);
  border: 1px solid var(--ab-rule-strong);
  border-radius: var(--r-pill);
  padding: 6px 14px;
  transition: background 0.24s var(--ease), color 0.24s var(--ease);
}

.page-about .ab-tl-jump a:hover,
.page-about .ab-tl-jump a:focus-visible {
  background: var(--cyan);
  color: var(--ink-900);
}

.page-about .ab-tl {
  list-style: none;
  margin: 0;
  padding: 4px 0 0 18px;
  border-left: 1px solid var(--ab-rule);
}

.page-about .ab-tl-item {
  position: relative;
  padding: 0 0 30px 20px;
  scroll-margin-top: 120px;
}

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

.page-about .ab-tl-item::before {
  content: "";
  position: absolute;
  left: -23px;
  top: 7px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--gold);
  box-shadow: 0 0 0 3px rgba(242, 200, 121, 0.16);
}

.page-about .ab-tl-year {
  display: inline-block;
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--gold);
  margin-bottom: 6px;
}

.page-about .ab-tl-item h3 {
  font-size: 17px;
  font-weight: 800;
  letter-spacing: 0.02em;
  color: var(--fog);
  margin: 0 0 8px;
}

.page-about .ab-tl-item p {
  font-size: 14px;
  line-height: 1.8;
  color: var(--glacier);
  margin: 0;
  max-width: 52ch;
}

/* ---------- 下一步 ---------- */

.page-about .ab-next {
  padding: 52px 0 68px;
  border-top: 1px solid var(--ab-rule);
  margin-top: 48px;
}

.page-about .ab-next h2 {
  font-size: clamp(21px, 4vw, 30px);
  font-weight: 800;
  letter-spacing: 0.03em;
  color: var(--fog);
  margin: 0 0 20px;
}

.page-about .ab-next-links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--ab-rule);
  border: 1px solid var(--ab-rule);
  border-radius: var(--r-m);
  overflow: hidden;
}

.page-about .ab-next-links a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 16px 18px;
  background: var(--ink-800);
  color: var(--fog);
  font-size: 15px;
  text-decoration: none;
  transition: background 0.24s var(--ease), color 0.24s var(--ease);
}

.page-about .ab-next-links a:hover,
.page-about .ab-next-links a:focus-visible {
  background: var(--ink-700);
  color: var(--cyan);
}

.page-about .ab-next-arrow {
  font-family: var(--font-num);
  color: var(--coral);
  flex: 0 0 auto;
}

/* ---------- 响应式 ---------- */

@media (min-width: 720px) {
  .page-about .ab-hero {
    padding-top: 34px;
  }

  .page-about .ab-hero-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 14px;
  }

  .page-about .ab-compare-grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  }

  .page-about .ab-compare-col {
    padding: 6px 0;
  }

  .page-about .ab-compare-col--past {
    border-bottom: 0;
    border-right: 1px solid var(--ab-rule);
    padding-right: clamp(20px, 3vw, 40px);
  }

  .page-about .ab-compare-col--now {
    padding-left: clamp(20px, 3vw, 44px);
  }

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

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

@media (min-width: 900px) {
  .page-about .ab-hero {
    padding-bottom: 56px;
  }

  .page-about .ab-hero-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: clamp(32px, 5vw, 64px);
    align-items: end;
  }

  .page-about .ab-hero-figure {
    align-self: start;
    margin-top: -10px;
  }

  .page-about .ab-chapter > .wrap {
    padding-left: calc(var(--gutter) + var(--ab-rail));
  }

  .page-about .ab-chapter {
    padding-top: 72px;
  }

  .page-about .ab-work {
    grid-template-columns: 56px minmax(0, 1fr);
    padding: 28px 0;
  }

  .page-about .ab-work:nth-child(2) {
    padding-left: 7%;
  }

  .page-about .ab-work:nth-child(3) {
    padding-left: 14%;
  }

  .page-about .ab-work-body h3 {
    font-size: 24px;
  }

  .page-about .ab-cat {
    grid-template-columns: minmax(0, 4fr) minmax(0, 7fr);
    gap: 32px;
    align-items: start;
    padding: 24px 0;
  }

  .page-about .ab-cat-head {
    align-content: flex-start;
  }

  .page-about .ab-cat-head h3 {
    font-size: 22px;
  }

  .page-about .ab-rec-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: 44px;
    align-items: start;
  }

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

  .page-about .ab-team-grid {
    grid-template-columns: minmax(0, 4fr) minmax(0, 7fr);
    gap: 48px;
    align-items: start;
  }

  .page-about .ab-partner-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: 44px;
    align-items: start;
  }

  .page-about .ab-tl {
    padding-left: 28px;
  }

  .page-about .ab-tl-item {
    padding: 0 0 40px 32px;
    display: grid;
    grid-template-columns: 96px minmax(0, 1fr);
    gap: 0 24px;
  }

  .page-about .ab-tl-item::before {
    left: -33px;
  }

  .page-about .ab-tl-year {
    grid-row: 1 / span 2;
    padding-top: 3px;
    margin-bottom: 0;
  }

  .page-about .ab-tl-item h3 {
    font-size: 19px;
  }

  .page-about .ab-tl-banner p {
    padding: 64px 26px 22px;
  }
}

@media (min-width: 1120px) {
  .page-about .ab-hero h1 {
    max-width: 16ch;
  }

  .page-about .ab-compare {
    padding: 56px 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-tl-jump a,
  .page-about .ab-next-links a {
    transition: none;
  }
}