.page-about {
  --ab-soft: rgba(38, 41, 43, 0.74);
  --ab-card: #FBF8F0;
  --ab-line: 1px solid var(--silver);
  --ab-heavy: 3px solid var(--ink);
  background: var(--paper);
  color: var(--ink);
  overflow-x: hidden;
}

.page-about .breadcrumb {
  padding-top: 14px;
  font-size: 12px;
  font-family: var(--font-data);
}

.page-about .breadcrumb__here {
  color: var(--ab-soft);
}

/* ---------- 首屏 ---------- */

.page-about .ab-open {
  padding-top: 26px;
}

.page-about .ab-open__grid {
  display: grid;
  gap: 26px;
  margin-top: 18px;
}

.page-about .ab-open__title {
  margin: 10px 0 0;
  font-size: clamp(30px, 8.4vw, 46px);
  line-height: 1.1;
  letter-spacing: -0.012em;
  max-width: 16em;
}

.page-about .ab-open__text {
  margin: 18px 0 0;
  max-width: 34em;
}

.page-about .ab-open__note {
  margin: 18px 0 0;
  padding: 2px 0 2px 14px;
  border-left: 3px solid var(--clay);
  font-size: 14px;
  line-height: 1.7;
  color: var(--ab-soft);
  max-width: 32em;
}

.page-about .ab-open__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

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

/* ---------- 区块标题 ---------- */

.page-about .ab-sec-head h2 {
  margin: 8px 0 0;
}

.page-about .ab-sec-head__intro {
  margin: 14px 0 0;
  max-width: 40em;
  color: var(--ab-soft);
  font-size: 16px;
  line-height: 1.75;
}

/* ---------- 时间轴 ---------- */

.page-about .ab-tl-wrap {
  display: grid;
  gap: 34px;
  margin-top: 30px;
}

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

.page-about .ab-tl__item {
  position: relative;
  padding: 0 0 34px 26px;
  border-left: 2px solid var(--silver);
}

.page-about .ab-tl__item:last-child {
  border-left-color: transparent;
  padding-bottom: 0;
}

.page-about .ab-tl__item::before {
  content: "";
  position: absolute;
  left: -8px;
  top: 5px;
  width: 14px;
  height: 14px;
  background: var(--paper);
  border: 3px solid var(--pitch);
  box-sizing: border-box;
}

.page-about .ab-tl__year {
  margin: 0;
  font-size: 22px;
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: 0.02em;
  color: var(--clay);
}

.page-about .ab-tl__title {
  margin: 6px 0 0;
}

.page-about .ab-tl__text {
  margin: 10px 0 0;
  max-width: 34em;
  font-size: 15px;
  line-height: 1.78;
  color: var(--ab-soft);
}

.page-about .ab-tl__more {
  margin-top: 12px;
}

.page-about .ab-tl__sum {
  display: inline-block;
  cursor: pointer;
  padding-bottom: 3px;
  font-family: var(--font-data);
  font-size: 12px;
  letter-spacing: 0.02em;
  color: var(--pitch);
  border-bottom: 1px dashed var(--silver);
  list-style: none;
}

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

.page-about .ab-tl__sum::before {
  content: "＋";
  margin-right: 6px;
  color: var(--clay);
}

.page-about .ab-tl__more[open] .ab-tl__sum::before {
  content: "－";
}

.page-about .ab-tl__sum:focus-visible {
  outline: 2px solid var(--pitch);
  outline-offset: 3px;
}

.page-about .ab-tl__more p {
  margin: 12px 0 0;
  max-width: 34em;
  font-size: 14px;
  line-height: 1.78;
  color: var(--ab-soft);
  padding-left: 12px;
  border-left: 2px solid var(--silver);
}

.page-about .ab-tl__aside {
  display: grid;
  gap: 22px;
  align-content: start;
}

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

.page-about .ab-tl__note p {
  margin: 0;
}

/* ---------- 团队 ---------- */

.page-about .ab-team__grid {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .ab-team__cell {
  display: grid;
  grid-template-columns: 64px minmax(0, 1fr);
  gap: 0 18px;
  align-items: start;
  padding: 20px 18px 22px;
  background: var(--ab-card);
  border: var(--ab-heavy);
  box-shadow: var(--shadow-soft);
  transition: box-shadow var(--t) ease, transform var(--t) ease;
}

.page-about .ab-team__cell:hover {
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-hard-sm);
}

.page-about .ab-team__num {
  margin: 2px 0 0;
  font-size: 30px;
  font-weight: 700;
  line-height: 1;
  color: var(--pitch);
}

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

.page-about .ab-team__desc {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--ab-soft);
}

/* ---------- 流程 ---------- */

.page-about .ab-flow__grid {
  display: grid;
  gap: 30px;
  margin-top: 30px;
}

.page-about .ab-flow__steps {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: var(--ab-heavy);
}

.page-about .ab-flow__step {
  display: grid;
  grid-template-columns: 46px minmax(0, 1fr);
  gap: 0 14px;
  padding: 20px 0 22px;
  border-bottom: 1px solid var(--silver);
}

.page-about .ab-flow__step h3 {
  margin: 0;
}

.page-about .ab-flow__step p {
  margin: 8px 0 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--ab-soft);
}

.page-about .ab-flow__idx {
  margin: 4px 0 0;
  font-size: 14px;
  font-weight: 700;
  color: var(--clay);
  letter-spacing: 0.06em;
}

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

/* ---------- 覆盖 ---------- */

.page-about .ab-reach__band {
  display: grid;
  gap: 1px;
  margin-top: 28px;
  background: var(--pitch);
  border: 3px solid var(--deep);
}

.page-about .ab-reach__cell {
  background: var(--deep);
  padding: 22px 20px 24px;
}

.page-about .ab-reach__num {
  margin: 0;
  font-size: 38px;
  font-weight: 700;
  line-height: 1;
  color: var(--lime);
}

.page-about .ab-reach__label {
  margin: 10px 0 0;
  font-size: 13px;
  line-height: 1.5;
  color: var(--silver);
}

.page-about .ab-reach__body {
  margin-top: 26px;
  display: grid;
  gap: 16px;
}

.page-about .ab-reach__body p {
  margin: 0;
  max-width: 40em;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ab-soft);
}

/* ---------- 协作 ---------- */

.page-about .ab-partners__grid {
  display: grid;
  gap: 16px;
  margin-top: 30px;
}

.page-about .ab-partners__card p {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--ab-soft);
}

.page-about .ab-partners__foot {
  margin: 26px 0 0;
  padding: 16px 0 0;
  border-top: var(--ab-line);
  max-width: 44em;
  font-size: 14px;
  line-height: 1.8;
  color: var(--ab-soft);
}

/* ---------- 下一步 ---------- */

.page-about .ab-next__panel {
  padding: 32px 22px 34px;
}

.page-about .ab-next__eyebrow {
  color: var(--lime);
}

.page-about .ab-next__title {
  margin: 10px 0 0;
  color: var(--paper);
  max-width: 18em;
}

.page-about .ab-next__text {
  margin: 16px 0 0;
  max-width: 38em;
  font-size: 15px;
  line-height: 1.8;
  color: var(--silver);
}

.page-about .ab-next__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.page-about .ab-next__ghost {
  color: var(--paper);
  border-color: var(--silver);
}

/* ---------- 断点 ---------- */

@media (min-width: 720px) {
  .page-about .ab-team__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

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

@media (min-width: 900px) {
  .page-about .ab-open {
    padding-top: 40px;
  }

  .page-about .ab-open__grid {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 1fr);
    gap: 48px;
    align-items: start;
  }

  .page-about .ab-next__panel {
    padding: 46px 48px 48px;
  }
}

@media (min-width: 960px) {
  .page-about .ab-tl-wrap {
    grid-template-columns: minmax(0, 1.62fr) minmax(0, 1fr);
    gap: 52px;
    align-items: start;
  }

  .page-about .ab-flow__grid {
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr);
    gap: 48px;
    align-items: start;
  }

  .page-about .ab-flow__fig {
    position: sticky;
    top: 96px;
  }
}

@media (min-width: 1080px) {
  .page-about .ab-reach__band {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

  .page-about .ab-team__cell:hover {
    transform: none;
  }
}