.page-about {
  --ay-col: 56px;
  --ay-axis: 23px;
  --ay-gap: 12px;
}

.page-about [id^="y-"] {
  scroll-margin-top: 150px;
}

/* ---------- 通用小标题 ---------- */
.page-about .about-secthead {
  max-width: 680px;
  margin-block-end: 40px;
}

.page-about .about-secthead h2 {
  font-family: var(--font-display);
  font-size: clamp(25px, 5vw, 40px);
  line-height: 1.18;
  letter-spacing: .01em;
  margin-block: 12px 14px;
  color: var(--text);
}

.page-about .about-secthead p {
  color: var(--text-dim);
  font-size: var(--fs-17);
  line-height: 1.75;
  max-width: 62ch;
}

.page-about .media-frame {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-lg);
  border: 1px solid var(--line);
  background: var(--ink-800);
}

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

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-block: 24px 80px;
}

.page-about .about-hero h1 {
  font-family: var(--font-display);
  font-size: clamp(32px, 7.4vw, 66px);
  line-height: 1.1;
  letter-spacing: .015em;
  margin-block: 14px 18px;
  max-width: 720px;
  color: var(--text);
}

.page-about .about-hero__lede {
  color: var(--text-dim);
  font-size: var(--fs-17);
  line-height: 1.85;
  max-width: 62ch;
}

.page-about .about-hero__stats {
  list-style: none;
  margin: 34px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-hero__stats li {
  background: var(--ink-800);
  padding: 16px 18px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.page-about .about-hero__stats .num {
  font-family: var(--font-mono);
  font-size: var(--fs-28);
  font-weight: 700;
  color: var(--lime);
  letter-spacing: -.01em;
  font-variant-numeric: tabular-nums;
}

.page-about .about-hero__stat-label {
  font-size: var(--fs-14);
  color: var(--text-dim);
}

.page-about .about-hero__figure {
  margin: 46px var(--gutter) 0;
  aspect-ratio: 3 / 2;
}

/* ---------- 时间轴 ---------- */
.page-about .timeline {
  padding-block: 20px 88px;
}

.page-about .timeline__scale {
  list-style: none;
  margin: 0 0 34px;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .timeline__tick {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: var(--fs-14);
  letter-spacing: .04em;
  color: var(--text-dim);
  text-decoration: none;
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 5px 14px;
  transition: color .2s var(--ease), background-color .2s var(--ease), border-color .2s var(--ease);
}

.page-about .timeline__tick:hover,
.page-about .timeline__tick:focus-visible {
  color: var(--ink-900);
  background: var(--lime);
  border-color: var(--lime);
}

.page-about .timeline__track {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .timeline__track::before {
  content: "";
  position: absolute;
  inset-block: 8px;
  left: var(--ay-axis);
  width: 2px;
  background: linear-gradient(180deg, var(--magenta), var(--cyan) 46%, var(--lime));
  opacity: .5;
}

.page-about .timeline__item {
  position: relative;
  display: grid;
  grid-template-columns: var(--ay-col) minmax(0, 1fr);
  gap: var(--ay-gap);
  padding-block: 18px;
}

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: calc(var(--ay-axis) - 5px);
  top: 26px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--ink-900);
  border: 2px solid var(--lime);
  box-sizing: border-box;
  transition: background-color .2s var(--ease), border-color .2s var(--ease);
}

.page-about .timeline__item:target::before {
  background: var(--lime);
  border-color: var(--lime);
}

.page-about .timeline__year {
  font-family: var(--font-mono);
  font-size: var(--fs-14);
  letter-spacing: .06em;
  color: var(--lime);
  padding-top: 3px;
  font-variant-numeric: tabular-nums;
}

.page-about .timeline__body {
  background: var(--ink-800);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px 18px 20px;
  transition: border-color .2s var(--ease), transform .2s var(--ease);
}

.page-about .timeline__body:hover {
  border-color: var(--magenta);
  transform: translateY(-2px);
}

.page-about .timeline__body h3 {
  font-size: var(--fs-22);
  font-weight: 800;
  line-height: 1.35;
  margin-block: 12px 8px;
  color: var(--text);
}

.page-about .timeline__body p {
  color: var(--text-dim);
  font-size: var(--fs-17);
  line-height: 1.75;
}

.page-about .timeline__shot {
  margin: 34px 0 34px var(--ay-col);
  aspect-ratio: 3 / 2;
}

/* ---------- 内容归档矩阵 ---------- */
.page-about .archive {
  padding-block: 16px 88px;
}

.page-about .archive__matrix {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

.page-about .archive__cell {
  position: relative;
  padding: 22px 20px 20px;
  border-radius: var(--radius);
  background: var(--ink-800);
  border: 1px solid var(--line);
  overflow: hidden;
  transition: border-color .2s var(--ease), background-color .2s var(--ease);
}

.page-about .archive__cell::after {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: var(--lime);
  transform: scaleY(0);
  transform-origin: top;
  transition: transform .22s var(--ease);
}

.page-about .archive__cell:nth-child(2)::after { background: var(--amber); }
.page-about .archive__cell:nth-child(3)::after { background: var(--magenta); }
.page-about .archive__cell:nth-child(4)::after { background: var(--cyan); }
.page-about .archive__cell:nth-child(5)::after { background: var(--lime); }

.page-about .archive__cell:hover,
.page-about .archive__cell:focus-within {
  border-color: var(--line);
  background: var(--ink-750);
}

.page-about .archive__cell:hover::after,
.page-about .archive__cell:focus-within::after {
  transform: scaleY(1);
}

.page-about .archive__code {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .16em;
  color: var(--text-dim);
}

.page-about .archive__cell h3 {
  font-size: var(--fs-22);
  font-weight: 800;
  margin-block: 8px 10px;
  color: var(--text);
}

.page-about .archive__cell > p {
  color: var(--text-dim);
  font-size: var(--fs-14);
  line-height: 1.75;
}

.page-about .archive__meta {
  margin: 18px 0 0;
  padding-top: 14px;
  border-top: 1px solid var(--line-soft);
  display: flex;
  flex-wrap: wrap;
  gap: 10px 22px;
}

.page-about .archive__meta > div {
  display: flex;
  align-items: baseline;
  gap: 8px;
}

.page-about .archive__meta dt {
  font-size: var(--fs-12);
  color: var(--text-dim);
  letter-spacing: .04em;
}

.page-about .archive__meta dd {
  margin: 0;
  font-size: var(--fs-14);
  color: var(--text);
}

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

/* ---------- 团队 ---------- */
.page-about .crew {
  padding-block: 16px 88px;
}

.page-about .crew__list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line-soft);
}

.page-about .crew__row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 6px 14px;
  padding: 18px 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .crew__role {
  font-size: var(--fs-22);
  font-weight: 800;
  color: var(--text);
}

.page-about .crew__count {
  font-family: var(--font-mono);
  font-size: var(--fs-17);
  color: var(--lime);
  text-align: right;
  font-variant-numeric: tabular-nums;
}

.page-about .crew__desc {
  grid-column: 1 / -1;
  font-size: var(--fs-17);
  line-height: 1.75;
  color: var(--text-dim);
}

.page-about .crew__shift {
  grid-column: 1 / -1;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .06em;
  color: var(--text-dim);
}

/* ---------- 合作 ---------- */
.page-about .partners {
  padding-block: 16px 88px;
}

.page-about .partners__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
  align-items: start;
}

.page-about .partners__text h2 {
  font-family: var(--font-display);
  font-size: clamp(25px, 5vw, 40px);
  line-height: 1.18;
  letter-spacing: .01em;
  margin-block: 12px 16px;
  color: var(--text);
}

.page-about .partners__text > p {
  color: var(--text-dim);
  font-size: var(--fs-17);
  line-height: 1.8;
  max-width: 60ch;
}

.page-about .partners__ways {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .partners__ways li {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .partners__ways li > span:last-child {
  font-size: var(--fs-14);
  color: var(--text-dim);
}

.page-about .partners__note {
  margin-block-start: 24px;
  font-size: var(--fs-14);
  line-height: 1.8;
  color: var(--text-dim);
}

.page-about .partners__note a {
  color: var(--lime);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .partners__figure {
  aspect-ratio: 3 / 2;
}

/* ---------- 翻面档案卡 ---------- */
.page-about .dossiers {
  padding-block: 16px 88px;
}

.page-about .dossiers__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.page-about .dossier {
  min-height: 268px;
  outline-offset: 4px;
}

.page-about .dossier > .flip-card__inner {
  height: 100%;
  min-height: 268px;
}

.page-about .dossier .flip-card__face {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  padding: 22px 20px;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  overflow: hidden;
}

.page-about .dossier .flip-card__face--front {
  background: linear-gradient(150deg, var(--ink-750) 0%, var(--ink-800) 62%, var(--ink-600) 100%);
}

.page-about .dossier .flip-card__face--back {
  background: linear-gradient(150deg, var(--card-back-a) 0%, var(--card-back-b) 100%);
  border-color: var(--magenta);
}

.page-about .dossier__kicker {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: .16em;
  color: var(--text-dim);
}

.page-about .dossier .flip-card__face--back .dossier__kicker {
  color: var(--amber);
}

.page-about .dossier h3 {
  font-size: var(--fs-22);
  font-weight: 800;
  line-height: 1.3;
  margin-block: 12px 10px;
  color: var(--text);
}

.page-about .dossier__lead,
.page-about .dossier .flip-card__face--back p:not(.dossier__kicker) {
  font-size: var(--fs-14);
  line-height: 1.75;
  color: var(--text-dim);
}

.page-about .dossier .flip-card__face--front .tag {
  margin-block-start: auto;
  align-self: flex-start;
}

/* ---------- 结尾入口 ---------- */
.page-about .about-cta {
  padding-block: 8px 96px;
}

.page-about .about-cta__inner {
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: linear-gradient(115deg, var(--ink-800) 0%, var(--ink-750) 52%, var(--ink-600) 100%);
  padding: 30px 22px;
  display: grid;
  gap: 24px;
}

.page-about .about-cta h2 {
  font-family: var(--font-display);
  font-size: clamp(24px, 4.6vw, 36px);
  line-height: 1.2;
  letter-spacing: .01em;
  margin-block-end: 12px;
  color: var(--text);
}

.page-about .about-cta p {
  font-size: var(--fs-17);
  line-height: 1.75;
  color: var(--text-dim);
  max-width: 58ch;
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 中等屏幕 ---------- */
@media (min-width: 720px) {
  .page-about {
    --ay-col: 92px;
    --ay-axis: 31px;
    --ay-gap: 20px;
  }

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

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

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

  .page-about .partners__grid {
    grid-template-columns: 5fr 4fr;
    gap: 40px;
  }

  .page-about .about-cta__inner {
    padding: 42px 40px;
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
  }
}

/* ---------- 宽屏 ---------- */
@media (min-width: 1000px) {
  .page-about .about-hero {
    padding-block: 36px 104px;
  }

  .page-about .about-hero__figure {
    margin-inline: var(--gutter);
  }

  .page-about .timeline__item {
    padding-block: 22px;
  }

  .page-about .timeline__item:nth-child(even) .timeline__body {
    margin-inline-start: 46px;
  }

  .page-about .archive__matrix {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }

  .page-about .archive__matrix > li:nth-child(1),
  .page-about .archive__matrix > li:nth-child(2),
  .page-about .archive__matrix > li:nth-child(3) {
    grid-column: span 2;
  }

  .page-about .archive__matrix > li:nth-child(4),
  .page-about .archive__matrix > li:nth-child(5) {
    grid-column: span 3;
  }

  .page-about .crew__row {
    grid-template-columns: 160px 88px minmax(0, 1fr) 168px;
    align-items: baseline;
    gap: 12px 22px;
  }

  .page-about .crew__desc,
  .page-about .crew__shift {
    grid-column: auto;
  }

  .page-about .crew__count {
    text-align: left;
  }

  .page-about .crew__shift {
    text-align: right;
  }

  .page-about .timeline__shot {
    margin-block: 44px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .timeline__body,
  .page-about .archive__cell,
  .page-about .timeline__tick {
    transition: none;
  }

  .page-about .timeline__body:hover {
    transform: none;
  }
}