.page-about {
  --about-gold-line: rgba(243, 196, 106, 0.22);
  --about-soft-line: rgba(233, 238, 250, 0.08);
  --about-measure: 68ch;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  gap: 16px;
  padding-top: 8px;
}

.page-about h1 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(30px, 5vw, 52px);
  line-height: 1.15;
  letter-spacing: -0.01em;
  color: var(--c-silver);
}

.page-about .about-hero .lede {
  max-width: var(--about-measure);
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: 10px;
  background: var(--about-soft-line);
  border: 1px solid var(--about-soft-line);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-fact {
  display: grid;
  gap: 6px;
  padding: 18px 20px;
  background: var(--c-indigo);
}

.page-about .about-fact-num {
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--c-cyan);
}

.page-about .about-fact-key {
  font-size: 13px;
  line-height: 1.6;
  color: var(--c-dust);
}

/* ---------- 我们做什么 ---------- */
.page-about .about-what-grid {
  display: grid;
  gap: 26px;
  margin-top: 30px;
}

.page-about .about-what-item {
  display: grid;
  gap: 10px;
  padding-top: 18px;
  border-top: 1px solid var(--about-gold-line);
}

.page-about .about-what-no {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--c-gold);
}

.page-about .about-what-item h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 700;
  line-height: 1.45;
  color: var(--c-silver);
}

.page-about .about-what-item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.9;
  color: var(--c-body);
}

/* ---------- 历程 ---------- */
.page-about .about-history-grid {
  display: grid;
  gap: 34px;
}

.page-about .about-history-main {
  min-width: 0;
}

.page-about .about-history-rail {
  display: grid;
  gap: 16px;
  align-content: start;
}

.page-about .about-history-media {
  margin: 0;
  aspect-ratio: 4 / 5;
  overflow: hidden;
  border-radius: var(--radius);
  border: 1px solid var(--about-soft-line);
}

.page-about .about-history-media img,
.page-about .about-team-media img,
.page-about .about-reach-media img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.page-about .hist-scale {
  list-style: none;
  margin: 0;
  padding: 0 0 0 16px;
  border-left: 1px solid var(--about-gold-line);
  display: grid;
  gap: 12px;
}

.page-about .hist-scale-item {
  display: flex;
  gap: 10px;
  align-items: baseline;
  font-size: 13px;
  line-height: 1.6;
  color: var(--c-dust);
}

.page-about .hist-scale-no {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--c-gold);
}

.page-about .hist-list {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
}

.page-about .hist-item {
  border-bottom: 1px solid var(--about-gold-line);
}

.page-about .hist-item:first-child {
  border-top: 1px solid var(--about-gold-line);
}

.page-about .hist-trigger {
  display: flex;
  align-items: center;
  gap: 18px;
  width: 100%;
  padding: 20px 2px;
  background: none;
  border: 0;
  border-radius: 0;
  color: inherit;
  text-align: left;
  cursor: pointer;
}

.page-about .hist-trigger .expand-icon {
  flex: none;
}

.page-about .hist-ver {
  flex: none;
  min-width: 2.1em;
  font-family: var(--font-mono);
  font-size: clamp(28px, 6vw, 52px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--c-dust);
  transition: color 200ms var(--ease);
}

.page-about .hist-trigger:hover .hist-ver,
.page-about .hist-trigger:focus-visible .hist-ver,
.page-about .hist-trigger[aria-expanded="true"] .hist-ver {
  color: var(--c-cyan);
}

.page-about .hist-head {
  flex: 1 1 auto;
  min-width: 0;
  display: grid;
  gap: 6px;
}

.page-about .hist-title {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  line-height: 1.45;
  color: var(--c-silver);
}

.page-about .hist-meta {
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.6;
  color: var(--c-dust);
}

.page-about .hist-item .expand-body p {
  margin: 0;
  max-width: var(--about-measure);
  font-size: 15px;
  line-height: 1.9;
  color: var(--c-body);
}

/* ---------- 团队 ---------- */
.page-about .about-team .filter-bar {
  margin-top: 22px;
}

.page-about .team-grid {
  margin-top: 22px;
}

.page-about .team-card {
  display: grid;
  grid-template-rows: auto 1fr;
  padding: 0;
  overflow: hidden;
}

.page-about .team-card-head {
  display: grid;
  gap: 6px;
  padding: 16px 18px;
  background: var(--c-glass);
  border-bottom: 1px solid var(--c-line);
}

.page-about .team-no {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--c-cyan);
}

.page-about .team-name {
  margin: 0;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--c-silver);
}

.page-about .team-card-body {
  display: grid;
  gap: 12px;
  align-content: start;
  padding: 18px;
}

.page-about .team-card-body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.9;
  color: var(--c-body);
}

.page-about .team-out {
  padding-top: 12px;
  border-top: 1px dashed var(--about-soft-line);
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.7;
  color: var(--c-dust);
}

.page-about .team-out-key {
  margin-right: 8px;
  color: var(--c-gold);
}

.page-about .about-team-media {
  margin: 30px 0 0;
  aspect-ratio: 15 / 8;
  overflow: hidden;
  border-radius: var(--radius);
  border: 1px solid var(--about-soft-line);
}

/* ---------- 服务范围 ---------- */
.page-about .about-reach-grid {
  display: grid;
  gap: 30px;
}

.page-about .about-reach-text {
  min-width: 0;
}

.page-about .about-reach-data {
  margin-top: 24px;
}

.page-about .about-reach-media {
  margin: 0;
  aspect-ratio: 2 / 1;
  overflow: hidden;
  border-radius: var(--radius);
  border: 1px solid var(--about-soft-line);
}

/* ---------- 更新时间标注 ---------- */
.page-about .update-steps {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
  display: grid;
  gap: 2px;
}

.page-about .update-step {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 6px 18px;
  padding: 20px 2px;
  border-bottom: 1px solid var(--about-soft-line);
}

.page-about .update-step-no {
  grid-column: 1;
  grid-row: 1 / span 2;
  padding-top: 4px;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--c-cyan);
}

.page-about .update-step h3 {
  grid-column: 2;
  margin: 0;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  line-height: 1.45;
  color: var(--c-silver);
}

.page-about .update-step p {
  grid-column: 2;
  margin: 0;
  max-width: var(--about-measure);
  font-size: 15px;
  line-height: 1.9;
  color: var(--c-body);
}

.page-about .about-update-note {
  margin: 24px 0 0;
  max-width: var(--about-measure);
  padding-left: 16px;
  border-left: 2px solid var(--c-gold-deep);
  font-size: 14px;
  line-height: 1.9;
  color: var(--c-dust);
}

.page-about .about-update-note a {
  color: var(--c-cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(56, 225, 210, 0.4);
}

.page-about .about-update-note a:hover {
  border-bottom-color: var(--c-cyan);
}

/* ---------- 合作四步 ---------- */
.page-about .coop-steps {
  list-style: none;
  margin: 32px 0 0;
  padding: 0;
  display: grid;
  gap: 26px;
}

.page-about .coop-step {
  display: grid;
  gap: 10px;
  align-content: start;
  padding-top: 18px;
  border-top: 2px solid var(--about-gold-line);
}

.page-about .coop-no {
  font-family: var(--font-mono);
  font-size: 26px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--c-gold);
}

.page-about .coop-title {
  margin: 0;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--c-silver);
}

.page-about .coop-text {
  margin: 0;
  font-size: 15px;
  line-height: 1.9;
  color: var(--c-body);
}

.page-about .coop-out {
  margin: 0;
  padding-top: 10px;
  border-top: 1px dashed var(--about-soft-line);
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.7;
  color: var(--c-dust);
}

.page-about .coop-out-key {
  margin-right: 8px;
  color: var(--c-cyan);
}

/* ---------- 结尾 ---------- */
.page-about .about-next-card {
  display: grid;
  gap: 14px;
  padding: 28px 24px;
  border-radius: var(--radius);
  border: 1px solid var(--c-line);
  background:
    linear-gradient(140deg, rgba(56, 225, 210, 0.1), rgba(76, 141, 255, 0.07) 46%, rgba(6, 10, 26, 0) 82%),
    var(--c-indigo);
}

.page-about .about-next-title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(22px, 3vw, 30px);
  font-weight: 800;
  line-height: 1.3;
  color: var(--c-silver);
}

.page-about .about-next-card p {
  margin: 0;
  max-width: var(--about-measure);
  font-size: 15px;
  line-height: 1.9;
  color: var(--c-body);
}

.page-about .about-next-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 4px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 620px) {
  .page-about .about-fact-num {
    font-size: 34px;
  }

  .page-about .about-next-card {
    padding: 36px 34px;
  }
}

@media (min-width: 780px) {
  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-fact-num {
    font-size: 36px;
  }

  .page-about .about-what-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 36px;
  }
}

@media (min-width: 860px) {
  .page-about .coop-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 32px 40px;
  }
}

@media (min-width: 960px) {
  .page-about .about-history-grid {
    grid-template-columns: 232px minmax(0, 1fr);
    gap: 56px;
    align-items: start;
  }

  .page-about .about-history-rail {
    position: sticky;
    top: calc(var(--bar-h) + 24px);
  }

  .page-about .about-reach-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: 48px;
    align-items: center;
  }
}

@media (min-width: 1160px) {
  .page-about .coop-steps {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 36px;
  }
}

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