.page-about {
  --ab-axis-w: 172px;
  --ab-edge: clamp(18px, 3vw, 40px);
  background: var(--ink);
  color: var(--bone);
  font-family: var(--font-body);
  line-height: 1.75;
}

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

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  position: relative;
  overflow: hidden;
  padding: calc(var(--header-h) + 28px) 0 clamp(48px, 7vw, 96px);
  background:
    radial-gradient(90% 72% at 88% 2%, rgba(108, 128, 104, 0.32), transparent 62%),
    linear-gradient(158deg, #0B2B26 0%, #0d3129 58%, #123a2f 100%);
}

.page-about .ab-hero::after {
  content: "";
  position: absolute;
  right: -12%;
  bottom: -38%;
  width: 74%;
  height: 260px;
  background: linear-gradient(90deg, transparent, rgba(102, 242, 210, 0.16));
  transform: skewY(-8deg);
  pointer-events: none;
}

.page-about .ab-hero__grid {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(32px, 5vw, 56px);
  margin-top: clamp(36px, 6vw, 80px);
}

.page-about .ab-hero__title {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: clamp(2.6rem, 8.4vw, 6.2rem);
  line-height: 0.9;
  letter-spacing: -0.02em;
  margin: 18px 0 0;
  color: var(--bone);
}

.page-about .ab-hero__lede {
  margin-top: clamp(20px, 3vw, 32px);
  max-width: 40ch;
  color: var(--dim);
  font-size: clamp(0.95rem, 1.2vw, 1.05rem);
}

.page-about .ab-plate {
  align-self: end;
  border: 1px solid rgba(102, 242, 210, 0.26);
  background: rgba(20, 24, 26, 0.5);
  padding: 22px 22px 18px;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 18px), calc(100% - 18px) 100%, 0 100%);
}

.page-about .ab-plate__label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--cyan);
  margin: 0 0 14px;
}

.page-about .ab-plate__rows {
  display: grid;
  gap: 2px;
}

.page-about .ab-plate__row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 12px;
  padding: 9px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .ab-plate__row:last-child {
  border-bottom: 0;
}

.page-about .ab-plate__key {
  font-size: 0.8rem;
  color: var(--dim);
  letter-spacing: 0.04em;
}

.page-about .ab-plate__value {
  font-family: var(--font-mono);
  font-size: 0.98rem;
  color: var(--bone);
  font-variant-numeric: tabular-nums;
}

.page-about .ab-plate__note {
  margin: 14px 0 0;
  padding-top: 12px;
  border-top: 1px solid var(--line);
  font-size: 0.76rem;
  color: var(--dim);
  line-height: 1.6;
}

/* ---------- 主体：轴 + 内容流 ---------- */
.page-about .ab-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
}

.page-about .ab-axis {
  display: flex;
  flex-direction: row;
  gap: 8px;
  overflow-x: auto;
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}

.page-about .ab-axis::-webkit-scrollbar {
  display: none;
}

.page-about .ab-axis__item {
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  flex: 0 0 auto;
  padding: 7px 12px;
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  color: var(--dim);
  text-decoration: none;
  border: 1px solid transparent;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 8px), calc(100% - 8px) 100%, 0 100%);
  transition: color var(--t) var(--ease), border-color var(--t) var(--ease), background var(--t) var(--ease);
  white-space: nowrap;
}

.page-about .ab-axis__num {
  font-size: 0.66rem;
  color: var(--cyan);
}

.page-about .ab-axis__item:hover,
.page-about .ab-axis__item:focus-visible {
  color: var(--cyan);
  border-color: rgba(102, 242, 210, 0.45);
  outline: none;
}

.page-about .ab-axis__item[aria-current="true"] {
  color: var(--ink);
  background: var(--cyan);
  border-color: var(--cyan);
}

.page-about .ab-axis__item[aria-current="true"] .ab-axis__num {
  color: var(--ink);
}

/* ---------- 章节通用 ---------- */
.page-about .ab-sec {
  position: relative;
  padding: clamp(52px, 8vw, 108px) 0;
  border-top: 1px solid var(--line);
}

.page-about .ab-sec__head {
  max-width: 44ch;
  margin-bottom: clamp(28px, 4vw, 48px);
}

.page-about .ab-sec__title {
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(1.9rem, 5vw, 3.5rem);
  line-height: 0.98;
  letter-spacing: -0.01em;
  margin: 14px 0 0;
  color: var(--bone);
}

.page-about .ab-sec__lede {
  margin-top: 18px;
  font-size: 0.95rem;
  color: var(--dim);
  max-width: 38ch;
}

.page-about .ab-sec--light {
  --line: rgba(20, 24, 26, 0.16);
  --line-strong: rgba(20, 24, 26, 0.4);
  --dim: rgba(20, 24, 26, 0.7);
  background: var(--bone);
  color: var(--ink-deep);
  padding-inline: var(--ab-edge);
  border-top: 0;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 26px), calc(100% - 26px) 100%, 0 100%);
}

.page-about .ab-sec--light .ab-sec__title {
  color: var(--ink-deep);
}

.page-about .ab-sec--light .by-figure__caption {
  color: rgba(20, 24, 26, 0.66);
}

/* ---------- 团队 ---------- */
.page-about .ab-team__figure {
  margin: 0 0 clamp(28px, 4vw, 44px);
}

.page-about .ab-acc {
  margin-top: 4px;
}

.page-about .ab-acc .by-accordion__trigger {
  display: flex;
  align-items: baseline;
  gap: 14px;
  width: 100%;
  text-align: left;
}

.page-about .ab-acc__num {
  font-size: 0.72rem;
  color: var(--cyan);
  letter-spacing: 0.08em;
  flex: 0 0 auto;
}

.page-about .ab-acc__title {
  font-size: 1rem;
  font-weight: 500;
  line-height: 1.4;
}

.page-about .ab-acc .by-accordion__panel p {
  margin: 0 0 12px;
  font-size: 0.92rem;
  color: var(--dim);
  max-width: 54ch;
}

.page-about .ab-acc .by-accordion__panel p:last-child {
  margin-bottom: 0;
}

/* ---------- 成稿路线 ---------- */
.page-about .ab-flow__wrap {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(28px, 4vw, 48px);
  align-items: start;
}

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

.page-about .ab-flow__step {
  position: relative;
  padding: 18px 0 18px 40px;
  border-bottom: 1px solid rgba(20, 24, 26, 0.14);
}

.page-about .ab-flow__step:last-child {
  border-bottom: 0;
}

.page-about .ab-flow__step::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 0;
  bottom: 0;
  width: 1px;
  background: rgba(20, 24, 26, 0.18);
}

.page-about .ab-flow__step::after {
  content: "";
  position: absolute;
  left: 3px;
  top: 26px;
  width: 11px;
  height: 11px;
  transform: rotate(45deg);
  background: var(--bone);
  border: 2px solid var(--moss);
}

.page-about .ab-flow__num {
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  color: var(--clay);
}

.page-about .ab-flow__name {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1.4rem;
  line-height: 1.2;
  margin: 4px 0 6px;
  color: var(--ink-deep);
}

.page-about .ab-flow__step p {
  margin: 0;
  font-size: 0.9rem;
  color: rgba(20, 24, 26, 0.72);
  max-width: 42ch;
}

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

.page-about .ab-flow__note {
  margin: clamp(28px, 4vw, 44px) 0 0;
  font-size: 0.88rem;
  color: rgba(20, 24, 26, 0.72);
  border-left: 3px solid var(--clay);
  padding-left: 16px;
  max-width: 62ch;
}

/* ---------- 年份 ---------- */
.page-about .ab-timeline {
  overflow-x: auto;
  padding-bottom: 12px;
  scrollbar-width: thin;
}

.page-about .ab-timeline__svg {
  display: block;
  width: 100%;
  min-width: 520px;
  height: auto;
}

.page-about .ab-tl-line {
  stroke: var(--moss);
  stroke-width: 2;
  stroke-dasharray: 6 8;
}

.page-about .ab-tl-dot {
  fill: var(--ink);
  stroke: var(--moss);
  stroke-width: 3;
  transition: stroke var(--t) var(--ease), r var(--t) var(--ease);
}

.page-about .ab-tl-dot--now {
  stroke: var(--cyan);
  stroke-width: 3.5;
}

.page-about .ab-tl-year {
  fill: var(--bone);
  font-family: var(--font-mono);
  font-size: 30px;
  letter-spacing: 0.04em;
  transition: fill var(--t) var(--ease);
}

.page-about .ab-tl-year--now {
  fill: var(--cyan);
}

.page-about .ab-tl-node:hover .ab-tl-dot {
  stroke: var(--cyan);
}

.page-about .ab-tl-node:hover .ab-tl-year {
  fill: var(--cyan);
}

.page-about .ab-tl-node {
  cursor: default;
}

.page-about .ab-eras {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 2px;
  margin-top: clamp(28px, 4vw, 48px);
  border-top: 1px solid var(--line);
}

.page-about .ab-era__card {
  padding: 22px 0 24px;
  border-bottom: 1px solid var(--line);
}

.page-about .ab-era__year {
  font-size: 1.6rem;
  color: var(--moss);
  line-height: 1;
  margin: 0 0 10px;
}

.page-about .ab-era__name {
  font-size: 1rem;
  font-weight: 500;
  margin: 0 0 8px;
  color: var(--bone);
}

.page-about .ab-era__card p:last-child {
  margin: 0;
  font-size: 0.88rem;
  color: var(--dim);
  max-width: 40ch;
}

/* ---------- 持续可用 ---------- */
.page-about .ab-metrics {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-about .ab-metric {
  background: rgba(63, 74, 69, 0.34);
  border: 1px solid var(--line);
  border-left: 3px solid var(--cyan);
  padding: 20px 18px 18px;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 14px), calc(100% - 14px) 100%, 0 100%);
}

.page-about .ab-metric--amber {
  border-left-color: var(--amber);
}

.page-about .ab-metric--tall {
  border-left-color: var(--moss);
}

.page-about .ab-metric__num {
  font-family: var(--font-mono);
  font-size: clamp(2rem, 4vw, 2.9rem);
  line-height: 1;
  color: var(--cyan);
  margin: 0 0 12px;
  display: flex;
  align-items: baseline;
  gap: 6px;
  font-variant-numeric: tabular-nums;
}

.page-about .ab-metric--amber .ab-metric__num {
  color: var(--amber);
}

.page-about .ab-metric--tall .ab-metric__num {
  color: var(--bone);
}

.page-about .ab-metric__unit {
  font-family: var(--font-body);
  font-size: 0.8rem;
  letter-spacing: 0.06em;
  color: var(--dim);
}

.page-about .ab-metric__label {
  margin: 0;
  font-size: 0.86rem;
  color: var(--dim);
  line-height: 1.65;
}

/* ---------- 合作生态 ---------- */
.page-about .ab-partners__wrap {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 4vw, 44px);
  align-items: start;
}

.page-about .ab-tags {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .ab-tag {
  cursor: help;
}

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

.page-about .ab-partners__note {
  margin: clamp(26px, 4vw, 40px) 0 0;
  font-size: 0.88rem;
  color: rgba(20, 24, 26, 0.72);
  border-left: 3px solid var(--moss);
  padding-left: 16px;
  max-width: 62ch;
}

/* ---------- 入口 ---------- */
.page-about .ab-entry__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 2px;
  border-top: 1px solid var(--line);
}

.page-about .ab-entry__card {
  display: block;
  padding: 22px 0;
  border-bottom: 1px solid var(--line);
  text-decoration: none;
  color: inherit;
  transition: background var(--t) var(--ease), padding-left var(--t) var(--ease);
}

.page-about .ab-entry__card:hover,
.page-about .ab-entry__card:focus-visible {
  background: rgba(102, 242, 210, 0.06);
  padding-left: 14px;
  outline: none;
}

.page-about .ab-entry__idx {
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  color: var(--cyan);
}

.page-about .ab-entry__name {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1.35rem;
  line-height: 1.25;
  margin: 6px 0 8px;
  color: var(--bone);
}

.page-about .ab-entry__card p {
  margin: 0 0 12px;
  font-size: 0.88rem;
  color: var(--dim);
  max-width: 40ch;
}

.page-about .ab-entry__more {
  font-size: 0.76rem;
  letter-spacing: 0.1em;
  color: var(--amber);
  border-bottom: 1px solid rgba(242, 163, 58, 0.5);
  padding-bottom: 2px;
}

.page-about .ab-entry__card:hover .ab-entry__more {
  color: var(--bone);
  border-bottom-color: var(--bone);
}

.page-about .ab-contact {
  margin-top: clamp(30px, 4vw, 48px);
  display: grid;
  gap: 0;
  border-top: 1px solid var(--line);
}

.page-about .ab-contact__row {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .ab-contact__key {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--moss);
}

.page-about .ab-contact__value {
  font-size: 0.92rem;
  color: var(--bone);
  text-decoration: none;
  word-break: break-word;
}

/* ---------- 断点 ---------- */
@media (min-width: 700px) {
  .page-about .ab-eras {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: clamp(20px, 4vw, 48px);
  }

  .page-about .ab-metrics {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
    align-items: start;
  }

  .page-about .ab-entry__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: clamp(20px, 4vw, 44px);
  }

  .page-about .ab-contact__row {
    flex-direction: row;
    justify-content: space-between;
    align-items: baseline;
    gap: 24px;
  }
}

@media (min-width: 980px) {
  .page-about .ab-hero__grid {
    grid-template-columns: minmax(0, 8fr) minmax(0, 4fr);
    align-items: end;
    gap: clamp(32px, 4vw, 64px);
  }

  .page-about .ab-body {
    grid-template-columns: var(--ab-axis-w) minmax(0, 1fr);
    gap: clamp(28px, 4vw, 64px);
    align-items: start;
  }

  .page-about .ab-axis {
    position: sticky;
    top: calc(var(--header-h) + 26px);
    flex-direction: column;
    gap: 4px;
    padding: 56px 0 0;
    border-bottom: 0;
    overflow: visible;
    align-self: start;
  }

  .page-about .ab-axis__item {
    display: flex;
    justify-content: flex-start;
    width: 100%;
    white-space: normal;
  }

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

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

  .page-about .ab-eras {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    column-gap: clamp(18px, 3vw, 36px);
  }

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

  .page-about .ab-metric--wide {
    grid-column: span 2;
  }

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

  .page-about .ab-entry__card {
    border-bottom: 0;
    border-top: 1px solid var(--line);
    padding: 24px 0 8px;
  }
}

@media (min-width: 1240px) {
  .page-about .ab-sec__head {
    max-width: 48ch;
  }

  .page-about .ab-timeline__svg {
    min-width: 100%;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-axis__item,
  .page-about .ab-entry__card,
  .page-about .ab-tl-dot,
  .page-about .ab-tl-year {
    transition: none;
  }
}