.page-about {
  --about-line: #1E2A44;
  --about-muted: rgba(199, 211, 224, 0.76);
  background: var(--ink);
  color: var(--mist);
  font-family: var(--font-body);
  line-height: 1.72;
  overflow-x: clip;
}

.page-about *,
.page-about *::before,
.page-about *::after {
  box-sizing: border-box;
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumb {
  padding: 20px 0 0;
}

/* ---------- 封面 ---------- */
.page-about .about-cover {
  position: relative;
  padding: 32px 0 56px;
  border-bottom: 2px solid var(--about-line);
  background-image:
    repeating-linear-gradient(0deg, rgba(30, 42, 68, 0.45) 0 1px, transparent 1px 88px),
    repeating-linear-gradient(90deg, rgba(30, 42, 68, 0.45) 0 1px, transparent 1px 88px);
}

.page-about .about-cover::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 80% 12%, rgba(0, 229, 255, 0.16), transparent 55%),
    radial-gradient(circle at 12% 92%, rgba(255, 107, 53, 0.12), transparent 52%);
  pointer-events: none;
  z-index: 0;
}

.page-about .about-cover > .container {
  position: relative;
  z-index: 1;
}

.page-about .about-kicker {
  margin: 0 0 18px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .about-cover-title {
  margin: 0 0 24px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(34px, 8vw, 82px);
  line-height: 1.04;
  letter-spacing: -0.02em;
  color: #fff;
  max-width: 15em;
}

.page-about .about-cover-lede {
  margin: 0 0 36px;
  padding-left: 18px;
  border-left: 3px solid var(--orange);
  font-size: clamp(16px, 2vw, 19px);
  line-height: 1.75;
  color: var(--mist);
  max-width: 60ch;
}

.page-about .about-cover-stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 2px;
  background: var(--about-line);
  border: 2px solid var(--about-line);
  max-width: 760px;
}

.page-about .about-cover-stats > li {
  background: var(--ink-deep);
  padding: 14px 16px 16px;
}

.page-about .about-cover-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(24px, 5vw, 36px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--cyan);
  font-variant-numeric: tabular-nums;
}

.page-about .about-cover-cap {
  display: block;
  margin-top: 8px;
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--about-muted);
}

@media (min-width: 700px) {
  .page-about .about-cover-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-cover {
    padding: 56px 0 80px;
  }
}

/* ---------- 外壳与右侧章节索引 ---------- */
.page-about .about-shell {
  padding-bottom: 56px;
}

.page-about .about-rail {
  display: none;
}

@media (min-width: 1200px) {
  .page-about .about-shell {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 130px;
    column-gap: 40px;
    align-items: start;
  }

  .page-about .about-rail {
    display: block;
    position: sticky;
    top: 150px;
    padding-top: 80px;
  }
}

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

.page-about .about-rail-link {
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 9px 0 9px 12px;
  border-left: 2px solid var(--about-line);
  text-decoration: none;
  color: var(--about-muted);
  transition: color var(--t-fast), border-color var(--t-fast);
}

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

.page-about .about-rail-num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  flex: 0 0 auto;
}

.page-about .about-rail-text {
  font-size: 12px;
  letter-spacing: 0.08em;
  white-space: nowrap;
}

/* ---------- 章节 ---------- */
.page-about .about-chapter {
  padding: 52px 0;
  border-top: 2px solid var(--about-line);
  scroll-margin-top: 160px;
}

.page-about .about-main > .about-chapter:first-child {
  border-top: 0;
  padding-top: 20px;
}

.page-about .about-chapter-grid {
  display: grid;
  gap: 18px;
}

@media (min-width: 860px) {
  .page-about .about-chapter-grid {
    grid-template-columns: 250px minmax(0, 1fr);
    column-gap: 48px;
    align-items: start;
  }
}

.page-about .about-num {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(46px, 9vw, 88px);
  line-height: 0.84;
  letter-spacing: -0.05em;
  color: var(--cyan);
  opacity: 0.4;
  font-variant-numeric: tabular-nums;
}

@supports (-webkit-text-stroke: 2px red) {
  .page-about .about-num {
    color: transparent;
    -webkit-text-stroke: 2px var(--cyan);
    opacity: 0.95;
  }
}

.page-about .about-title {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(20px, 3.2vw, 29px);
  line-height: 1.2;
  letter-spacing: -0.01em;
  color: #fff;
}

.page-about .about-chapter-body > p {
  margin: 0 0 18px;
  font-size: 16px;
  line-height: 1.78;
  color: var(--mist);
  max-width: 62ch;
}

.page-about .about-chapter-body .about-lede {
  font-size: 17px;
  font-weight: 500;
  color: #fff;
  padding-left: 16px;
  border-left: 3px solid var(--cyan);
  max-width: 58ch;
}

/* ---------- 配图 ---------- */
.page-about .about-figure {
  margin: 26px 0;
  border: 2px solid var(--about-line);
  box-shadow: var(--hard);
  background: var(--ink-deep);
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(0.88) contrast(1.05);
}

.page-about .about-figure figcaption {
  padding: 12px 16px;
  border-top: 2px solid var(--about-line);
  font-size: 13px;
  line-height: 1.6;
  color: var(--about-muted);
}

/* ---------- 数据流阶梯 ---------- */
.page-about .about-flow {
  list-style: none;
  margin: 24px 0 28px;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .about-flow-item {
  padding: 18px 18px 20px;
  background: var(--teal);
  border: 2px solid var(--about-line);
  border-top: 3px solid var(--cyan);
}

.page-about .about-flow-index {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--green);
}

.page-about .about-flow-time {
  margin: 10px 0 10px;
  font-family: var(--font-mono);
  font-size: 26px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: #fff;
  font-variant-numeric: tabular-nums;
}

.page-about .about-flow-text {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--mist);
}

@media (min-width: 820px) {
  .page-about .about-flow {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-flow-item:nth-child(2) {
    margin-top: 36px;
  }

  .page-about .about-flow-item:nth-child(3) {
    margin-top: 72px;
  }
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  list-style: none;
  margin: 4px 0 4px;
  padding: 0;
  display: grid;
  gap: 2px;
  background: var(--about-line);
  border: 2px solid var(--about-line);
}

@media (min-width: 640px) {
  .page-about .about-team {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.page-about .about-team-item {
  background: var(--ink-deep);
  padding: 18px 18px 20px;
}

.page-about .about-team-num {
  font-family: var(--font-mono);
  font-size: 32px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--orange);
  font-variant-numeric: tabular-nums;
}

.page-about .about-team-role {
  margin: 10px 0 6px;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 800;
  letter-spacing: 0.01em;
  color: #fff;
}

.page-about .about-team-item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.68;
  color: var(--about-muted);
}

/* ---------- 时间线 ---------- */
.page-about .about-figure--band {
  margin-top: 8px;
}

.page-about .about-timeline {
  position: relative;
  margin-top: 26px;
  padding-left: 26px;
}

.page-about .about-timeline-axis {
  position: absolute;
  left: 5px;
  top: 10px;
  width: 2px;
  height: calc(100% - 20px);
  display: block;
}

.page-about .about-node {
  position: relative;
  border-bottom: 2px solid var(--about-line);
}

.page-about .about-node::before {
  content: "";
  position: absolute;
  left: -25px;
  top: 24px;
  width: 12px;
  height: 12px;
  background: var(--ink);
  border: 2px solid var(--about-line);
  transition: background var(--t-fast), border-color var(--t-fast);
}

.page-about .about-node:hover::before {
  border-color: var(--cyan);
}

.page-about .about-node-trigger {
  display: flex;
  align-items: baseline;
  gap: 14px;
  width: 100%;
  padding: 18px 0;
  margin: 0;
  background: none;
  border: 0;
  text-align: left;
  cursor: pointer;
  font-family: inherit;
  color: inherit;
}

.page-about .about-node-trigger:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

.page-about .about-node-year {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 20px;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--cyan);
  font-variant-numeric: tabular-nums;
}

.page-about .about-node-head {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.4;
  color: #fff;
  transition: color var(--t-fast);
}

.page-about .about-node-trigger:hover .about-node-head,
.page-about .about-node-trigger[aria-expanded="true"] .about-node-head {
  color: var(--cyan);
}

.page-about .about-node .accordion-panel-inner p {
  margin: 0 0 18px;
  font-size: 15px;
  line-height: 1.74;
  color: var(--mist);
  max-width: 58ch;
}

/* ---------- 数据带 ---------- */
.page-about .about-band {
  margin: 34px 0 4px;
  padding: 22px;
  background: var(--ink-deep);
  border: 2px solid var(--about-line);
  box-shadow: var(--hard);
}

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

@media (min-width: 720px) {
  .page-about .about-stat-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

.page-about .about-stat {
  background: var(--ink);
  padding: 16px 14px 18px;
}

.page-about .about-stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(24px, 4vw, 34px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--cyan);
  font-variant-numeric: tabular-nums;
}

.page-about .about-stat-label {
  display: block;
  margin-top: 9px;
  font-size: 12.5px;
  line-height: 1.5;
  letter-spacing: 0.04em;
  color: var(--about-muted);
}

/* ---------- 合作生态 ---------- */
.page-about .about-partner-group {
  display: grid;
  gap: 2px;
  margin: 4px 0 26px;
  background: var(--about-line);
  border: 2px solid var(--about-line);
}

@media (min-width: 700px) {
  .page-about .about-partner-group {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .about-partner-card {
  background: var(--indigo);
  padding: 20px 18px 22px;
}

.page-about .about-partner-num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: #fff;
  font-variant-numeric: tabular-nums;
}

.page-about .about-partner-title {
  margin: 12px 0 8px;
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--cyan);
}

.page-about .about-partner-card > p:not(.about-partner-num) {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: rgba(242, 245, 247, 0.84);
}

.page-about .about-awards {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .about-awards li {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 14px 16px;
  background: var(--wine);
  border-left: 4px solid var(--amber);
}

.page-about .about-award-year {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--amber);
  font-variant-numeric: tabular-nums;
}

.page-about .about-award-name {
  font-size: 15px;
  line-height: 1.5;
  color: #fff;
}

/* ---------- 下一步 ---------- */
.page-about .about-next-list {
  list-style: none;
  margin: 4px 0 28px;
  padding: 0;
  display: grid;
  gap: 16px;
  max-width: 62ch;
}

.page-about .about-next-list li {
  position: relative;
  padding-left: 20px;
  font-size: 15.5px;
  line-height: 1.74;
  color: var(--mist);
}

.page-about .about-next-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 8px;
  height: 8px;
  background: var(--green);
}

.page-about .about-next-list strong {
  color: #fff;
  font-weight: 700;
}

.page-about .about-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}