.page-about {
  background: var(--ash);
  color: var(--ink);
  font-family: var(--font-body);
  overflow-x: hidden;
}

.page-about .about-crumbs {
  padding-top: 20px;
}

.page-about .crumbs__list {
  flex-wrap: wrap;
  row-gap: 6px;
}

/* ---------- 首屏档案头 ---------- */
.page-about .about-hero {
  position: relative;
  margin-top: 16px;
  padding: 26px 20px 24px;
  background: var(--paper);
  border: 1px solid var(--line-strong);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    repeating-linear-gradient(0deg, var(--line) 0 1px, transparent 1px 64px),
    repeating-linear-gradient(90deg, var(--line) 0 1px, transparent 1px 64px);
  opacity: .5;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  top: 0;
  right: 22px;
  width: 2px;
  height: 100%;
  background: linear-gradient(180deg, var(--vermilion), transparent 62%);
  opacity: .8;
  pointer-events: none;
}

.page-about .about-hero > * {
  position: relative;
  z-index: 1;
}

.page-about .about-hero__eyebrow {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--iron);
}

.page-about .about-hero__title {
  margin: 0;
  max-width: 20ch;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(32px, 7.6vw, 62px);
  line-height: 1.04;
  letter-spacing: -.02em;
  color: var(--ink-green);
}

.page-about .about-hero__lede {
  margin: 18px 0 0;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink);
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 24px 0 0;
  background: var(--line-strong);
  border: 1px solid var(--line-strong);
}

.page-about .about-stat {
  background: var(--ash);
  padding: 12px 14px 14px;
}

.page-about .about-stat__key {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--iron);
}

.page-about .about-stat__val {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 22px;
  letter-spacing: -.01em;
  color: var(--ink-green);
}

.page-about .about-stat__val .num {
  color: var(--vermilion);
  font-size: 26px;
  margin-right: 2px;
}

/* ---------- 左索引 / 右正文 ---------- */
.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 30px;
  padding-top: 34px;
  padding-bottom: 60px;
}

.page-about .about-rail {
  border-left: 3px solid var(--ink-green);
  padding: 4px 0 4px 16px;
}

.page-about .about-rail__title {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--iron);
}

.page-about .about-rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 6px 8px;
}

.page-about .about-rail__link {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 6px 10px;
  font-size: 14px;
  color: var(--ink-green);
  text-decoration: none;
  border: 1px solid var(--line);
  background: transparent;
  transition: background .25s var(--ease), border-color .25s var(--ease), transform .25s var(--ease);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  background: var(--paper);
  border-color: var(--cyan);
  transform: translateX(2px);
}

.page-about .about-rail__link:focus-visible {
  outline: 2px solid var(--violet);
  outline-offset: 2px;
}

.page-about .about-rail__num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .06em;
  color: var(--vermilion);
}

.page-about .about-rail__note {
  margin: 14px 0 0;
  max-width: 28ch;
  font-size: 12px;
  line-height: 1.7;
  color: var(--iron);
}

/* ---------- 章节通用 ---------- */
.page-about .about-section {
  padding: 34px 0 0;
  margin-top: 34px;
  border-top: 1px solid var(--line-strong);
}

.page-about .about-section:first-child {
  margin-top: 0;
  padding-top: 0;
  border-top: 0;
}

.page-about .about-sec-head {
  display: flex;
  align-items: baseline;
  gap: 12px;
}

.page-about .about-sec-num {
  flex: none;
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 24px;
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--vermilion);
}

.page-about .about-sec-title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(22px, 4.6vw, 36px);
  line-height: 1.14;
  letter-spacing: -.015em;
  color: var(--ink-green);
}

.page-about .about-sec-label {
  margin: 10px 0 20px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--iron);
  border-left: 2px solid var(--signal);
  padding-left: 8px;
}

.page-about .about-prose {
  max-width: 68ch;
}

.page-about .about-prose p {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink);
}

.page-about .about-prose p:last-child {
  margin-bottom: 0;
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  position: relative;
  margin: 26px 0 0;
  background: var(--paper);
  border: 1px solid var(--line-strong);
  padding: 8px;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(.72) contrast(1.03);
}

.page-about .about-figure__tag {
  position: absolute;
  top: 18px;
  left: 18px;
  background: var(--vermilion);
  color: var(--paper);
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .12em;
  text-transform: uppercase;
  padding: 5px 9px;
}

.page-about .about-figure__cap {
  margin: 10px 4px 2px;
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--iron);
}

.page-about .about-inline-link {
  margin: 20px 0 0;
}

.page-about .about-link {
  display: inline-block;
  font-size: 14px;
  color: var(--ink-green);
  text-decoration: none;
  border-bottom: 2px solid var(--signal);
  padding-bottom: 2px;
  transition: color .25s var(--ease), border-color .25s var(--ease);
}

.page-about .about-link:hover,
.page-about .about-link:focus-visible {
  color: var(--vermilion);
  border-color: var(--vermilion);
}

.page-about .about-link:focus-visible {
  outline: 2px solid var(--violet);
  outline-offset: 3px;
}

/* ---------- 团队矩阵 ---------- */
.page-about .about-crew-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
}

.page-about .team-matrix {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-about .team-card {
  background: var(--paper);
  border: 1px solid var(--line-strong);
  border-top: 3px solid var(--ink-green);
  padding: 16px 16px 14px;
  transition: transform .3s var(--ease), border-top-color .3s var(--ease), box-shadow .3s var(--ease);
}

.page-about .team-card:hover,
.page-about .team-card:focus-within {
  transform: translateY(-4px);
  border-top-color: var(--cyan);
  box-shadow: 0 10px 24px rgba(18, 42, 34, .1);
}

.page-about .team-card__idx {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .16em;
  color: var(--vermilion);
}

.page-about .team-card__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 20px;
  letter-spacing: -.01em;
  color: var(--ink-green);
}

.page-about .team-card__brief {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--ink);
}

.page-about .team-card__more {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--iron);
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  transition: max-height .4s var(--ease), opacity .3s var(--ease), margin .3s var(--ease);
}

.page-about .team-card:hover .team-card__more,
.page-about .team-card:focus-within .team-card__more {
  max-height: 220px;
  opacity: 1;
  margin: 10px 0 0;
}

.page-about .team-card__link {
  display: inline-block;
  margin-top: 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--ink-green);
  text-decoration: none;
  border-bottom: 1px solid var(--line-strong);
  padding-bottom: 2px;
}

.page-about .team-card__link:hover,
.page-about .team-card__link:focus-visible {
  color: var(--vermilion);
  border-color: var(--vermilion);
}

.page-about .team-card__link:focus-visible {
  outline: 2px solid var(--violet);
  outline-offset: 2px;
}

/* ---------- 合作网络 ---------- */
.page-about .network-list {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .network-item {
  background: var(--ash);
  border: 1px solid var(--line);
  border-left: 4px solid var(--signal);
  padding: 16px 16px 18px;
  transition: background .3s var(--ease), border-left-color .3s var(--ease);
}

.page-about .network-item:hover {
  background: var(--paper);
  border-left-color: var(--vermilion);
}

.page-about .network-item__title {
  margin: 10px 0 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 19px;
  letter-spacing: -.01em;
  color: var(--ink-green);
}

.page-about .network-item p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--ink);
}

/* ---------- 版本时间线 ---------- */
.page-about .about-timeline-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
}

.page-about .timeline {
  position: relative;
  list-style: none;
  margin: 4px 0 0;
  padding: 0 0 0 26px;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: linear-gradient(180deg, var(--vermilion), var(--signal) 55%, var(--cyan));
}

.page-about .tl-item {
  position: relative;
  padding: 0 0 22px;
}

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

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: -25px;
  top: 6px;
  width: 10px;
  height: 10px;
  background: var(--paper);
  border: 2px solid var(--vermilion);
  transform: rotate(45deg);
  transition: background .3s var(--ease), border-color .3s var(--ease);
}

.page-about .tl-item:hover::before,
.page-about .tl-item:focus-within::before {
  background: var(--signal);
  border-color: var(--ink-green);
}

.page-about .tl-item__year {
  margin: 0 0 4px;
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 20px;
  letter-spacing: -.01em;
  color: var(--ink-green);
}

.page-about .tl-item__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 18px;
  line-height: 1.3;
  color: var(--ink-green);
}

.page-about .tl-item__summary {
  margin: 0;
  max-width: 56ch;
  font-size: 14px;
  line-height: 1.78;
  color: var(--iron);
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  transition: max-height .4s var(--ease), opacity .3s var(--ease), margin .3s var(--ease);
}

.page-about .tl-item:hover .tl-item__summary,
.page-about .tl-item:focus-within .tl-item__summary {
  max-height: 180px;
  opacity: 1;
  margin-top: 8px;
}

.page-about .tl-item__link {
  display: inline-block;
  margin-top: 8px;
  font-size: 13px;
  color: var(--ink-green);
  text-decoration: none;
  border-bottom: 1px dashed var(--line-strong);
}

.page-about .tl-item__link:hover,
.page-about .tl-item__link:focus-visible {
  color: var(--vermilion);
  border-color: var(--vermilion);
}

.page-about .tl-item__link:focus-visible {
  outline: 2px solid var(--violet);
  outline-offset: 2px;
}

.page-about .about-figure--stack {
  margin-top: 0;
}

/* ---------- 认可与 CTA ---------- */
.page-about .award-list {
  list-style: none;
  margin: 0 0 22px;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .award-item {
  display: flex;
  align-items: center;
  gap: 10px;
  background: var(--paper);
  border: 1px solid var(--line-strong);
  padding: 10px 14px;
}

.page-about .award-item__text {
  margin: 0;
  font-size: 14px;
  color: var(--ink-green);
}

.page-about .about-cta {
  margin-top: 26px;
  padding: 22px 20px;
  background: var(--ink-green);
  border-top: 4px solid var(--vermilion);
}

.page-about .about-cta__text {
  margin: 0 0 16px;
  max-width: 46ch;
  font-size: 15px;
  line-height: 1.75;
  color: var(--paper);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .about-cta .btn {
  display: inline-block;
  padding: 10px 18px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  text-decoration: none;
  border: 1px solid transparent;
  transition: transform .25s var(--ease), background .25s var(--ease), color .25s var(--ease);
}

.page-about .about-cta .btn--accent {
  background: var(--signal);
  color: var(--ink-green);
}

.page-about .about-cta .btn--ghost {
  background: transparent;
  color: var(--paper);
  border-color: var(--line-light);
}

.page-about .about-cta .btn:hover,
.page-about .about-cta .btn:focus-visible {
  transform: translateY(-2px);
}

.page-about .about-cta .btn--ghost:hover,
.page-about .about-cta .btn--ghost:focus-visible {
  border-color: var(--cyan);
  color: var(--cyan);
}

.page-about .about-cta .btn:focus-visible {
  outline: 2px solid var(--violet);
  outline-offset: 3px;
}

/* ---------- 平板及以上 ---------- */
@media (min-width: 720px) {
  .page-about .about-hero {
    padding: 34px 32px 30px;
  }

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

  .page-about .team-matrix {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px;
  }

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

  .page-about .network-item:first-child {
    grid-column: 1 / -1;
  }
}

/* ---------- 桌面：左坐标柱 + 右档案栏 ---------- */
@media (min-width: 960px) {
  .page-about .about-shell {
    grid-template-columns: 232px minmax(0, 1fr);
    gap: clamp(30px, 4vw, 58px);
    padding-top: 46px;
  }

  .page-about .about-rail {
    position: sticky;
    top: 104px;
    align-self: start;
  }

  .page-about .about-rail__list {
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 2px;
  }

  .page-about .about-rail__link {
    display: flex;
    width: 100%;
    border: 0;
    border-left: 2px solid transparent;
    padding: 8px 10px;
  }

  .page-about .about-rail__link:hover,
  .page-about .about-rail__link:focus-visible {
    background: var(--paper);
    border-left-color: var(--cyan);
    transform: translateX(3px);
  }

  .page-about .about-section {
    padding-top: 44px;
    margin-top: 44px;
  }

  .page-about .about-hero__lede {
    font-size: 17px;
  }

  .page-about .about-figure {
    margin-top: 30px;
  }

  .page-about .about-prose p {
    font-size: 16.5px;
  }

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

  .page-about .network-item:first-child {
    grid-column: auto;
  }

  .page-about .about-crew-layout {
    grid-template-columns: minmax(0, 1fr);
  }

  .page-about .about-timeline-layout {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, .85fr);
    gap: 34px;
    align-items: start;
  }

  .page-about .about-figure--side {
    max-width: 100%;
  }
}

@media (min-width: 1120px) {
  .page-about .about-hero {
    padding: 42px 44px 36px;
  }

  .page-about .about-hero__title {
    max-width: 18ch;
  }

  .page-about .about-crew-layout {
    grid-template-columns: minmax(0, .85fr) minmax(0, 1.15fr);
    align-items: start;
    gap: 30px;
  }

  .page-about .about-prose--crew {
    position: sticky;
    top: 112px;
  }
}

/* ---------- 窄屏：展开态常显，避免触摸设备读不到 ---------- */
@media (max-width: 719px) {
  .page-about .team-card__more,
  .page-about .tl-item__summary {
    max-height: none;
    opacity: 1;
    margin-top: 8px;
  }

  .page-about .about-sec-title {
    max-width: 22ch;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .team-card,
  .page-about .team-card__more,
  .page-about .tl-item__summary,
  .page-about .about-rail__link,
  .page-about .network-item,
  .page-about .about-cta .btn {
    transition-duration: .01ms;
  }

  .page-about .team-card:hover,
  .page-about .team-card:focus-within,
  .page-about .about-cta .btn:hover,
  .page-about .about-cta .btn:focus-visible {
    transform: none;
  }
}