.page-about {
  --about-side: 240px;
  --about-gap: clamp(32px, 5vw, 72px);
  --about-sticky: calc(var(--header-h-sm) + 32px);
  --tl-line-x: 6px;
  --tl-pad: 30px;
}

/* 面包屑下的呼吸 */
.page-about .breadcrumbs {
  padding-top: 24px;
}

/* 首屏 */
.page-about .about-hero {
  padding: 40px 0 32px;
}

.page-about .about-h1 {
  margin: 16px 0 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(32px, 6.4vw, 68px);
  line-height: 1.08;
  letter-spacing: -0.02em;
  color: var(--ice);
  max-width: 18em;
}

.page-about .about-lede {
  margin: 24px 0 0;
  max-width: 40em;
  font-size: 17px;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .about-banner {
  margin: 24px auto 0;
  max-width: var(--max);
  padding: 0 var(--gutter);
}

.page-about .about-banner img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  border-radius: var(--r-card);
  border: 1px solid var(--line);
  background: linear-gradient(135deg, var(--sea), var(--deep) 55%, var(--night));
}

/* 主布局：左侧目录 + 右侧长文 */
.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gap);
  padding: var(--sp-72) 0 var(--sp-96);
}

.page-about .about-toc-title {
  margin: 0 0 12px;
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--mist);
}

.page-about .about-toc-list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 6px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-toc-list li {
  flex: 0 0 auto;
}

.page-about .about-toc-list a {
  display: block;
  padding: 8px 14px;
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  font-size: 14px;
  color: var(--mist);
  text-decoration: none;
  white-space: nowrap;
  transition: color 160ms var(--ease), border-color 160ms var(--ease), background-color 160ms var(--ease);
}

.page-about .about-toc-list a:hover,
.page-about .about-toc-list a:focus-visible {
  color: var(--neon);
  border-color: var(--neon);
  background: rgba(75, 240, 206, 0.08);
}

/* 章节 */
.page-about .about-body {
  min-width: 0;
}

.page-about .about-chapter {
  padding-bottom: var(--sp-72);
  border-bottom: 1px solid var(--line);
  margin-bottom: var(--sp-72);
}

.page-about .about-chapter:last-child {
  border-bottom: 0;
  margin-bottom: 0;
  padding-bottom: 0;
}

.page-about .about-chapter .section-title {
  margin: 0 0 20px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(24px, 3.4vw, 40px);
  line-height: 1.2;
  letter-spacing: -0.01em;
  color: var(--ice);
}

.page-about .about-chapter-lede {
  margin: 0 0 28px;
  max-width: 36em;
  color: var(--mist);
  font-size: 17px;
  line-height: 1.75;
}

.page-about .about-chapter p {
  max-width: 36em;
  margin: 0 0 18px;
  font-size: 17px;
  line-height: 1.8;
  color: var(--ice);
}

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

.page-about .about-chapter p b {
  color: var(--neon);
  font-weight: 700;
}

.page-about .about-quote {
  font-family: var(--font-editorial);
  font-weight: 600;
  font-size: clamp(20px, 2.6vw, 26px);
  line-height: 1.5;
  color: var(--neon);
  border-left: 2px solid var(--neon);
  padding-left: 18px;
  margin-bottom: 24px !important;
}

.page-about .about-points {
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--r-card);
  overflow: hidden;
}

.page-about .about-points li {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 16px;
  padding: 16px 20px;
  background: var(--deep);
  font-size: 16px;
  line-height: 1.7;
  color: var(--ice);
}

.page-about .pt-key {
  flex: 0 0 96px;
  color: var(--mist);
  font-size: 13px;
  letter-spacing: 0.08em;
  align-self: center;
}

/* 时间轴 */
.page-about .about-timeline {
  position: relative;
  margin: 8px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  top: 10px;
  bottom: 24px;
  left: var(--tl-line-x);
  width: 1px;
  background: linear-gradient(180deg, var(--neon), var(--violet) 60%, rgba(138, 107, 255, 0));
}

.page-about .tl-item {
  position: relative;
  padding-left: var(--tl-pad);
  padding-bottom: 40px;
}

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

.page-about .tl-dot {
  position: absolute;
  left: calc(var(--tl-line-x) - 6px);
  top: 10px;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  background: var(--night);
  border: 2px solid var(--neon);
  box-shadow: 0 0 0 5px rgba(75, 240, 206, 0.1);
  transition: background-color 200ms var(--ease), box-shadow 200ms var(--ease);
}

.page-about .tl-item:hover .tl-dot {
  background: var(--neon);
  box-shadow: 0 0 0 8px rgba(75, 240, 206, 0.16);
}

.page-about .tl-year {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 34px;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--neon);
  transition: color 200ms var(--ease);
}

.page-about .tl-item:hover .tl-year {
  color: var(--violet);
}

.page-about .tl-body h3 {
  margin: 0 0 8px;
  font-size: 19px;
  line-height: 1.4;
  color: var(--ice);
}

.page-about .tl-body p {
  margin: 0;
  max-width: 32em;
  font-size: 16px;
  line-height: 1.75;
  color: var(--mist);
}

/* 7:5 双栏 */
.page-about .about-split {
  display: grid;
  gap: 28px;
  margin-top: 32px;
}

.page-about .about-h3 {
  margin: 0 0 16px;
  font-size: 20px;
  color: var(--ice);
}

.page-about .about-tags {
  margin: 0;
}

.page-about .about-tags dt {
  margin-top: 16px;
}

.page-about .about-tags dt:first-child {
  margin-top: 0;
}

.page-about .about-tags dd {
  margin: 8px 0 0;
  font-size: 16px;
  line-height: 1.75;
  color: var(--mist);
}

.page-about .about-split-fig img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 2 / 1;
  object-fit: cover;
  border-radius: var(--r-card);
  border: 1px solid var(--line);
  background: linear-gradient(120deg, var(--deep), var(--sea));
}

.page-about .media-frame figcaption {
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--mist);
}

/* 团队 */
.page-about .team-grid {
  display: grid;
  gap: 16px;
  margin-top: 8px;
}

.page-about .team-cell {
  padding: 26px 22px;
  background: var(--deep);
  border: 1px solid var(--line);
  border-radius: var(--r-card);
  transition: border-color 200ms var(--ease), transform 120ms var(--ease);
}

.page-about .team-cell:hover {
  border-color: var(--neon);
  transform: translateY(-2px);
}

.page-about .team-cell--lead {
  background: linear-gradient(160deg, rgba(75, 240, 206, 0.12), var(--deep) 62%);
  border-color: rgba(75, 240, 206, 0.45);
}

.page-about .team-num {
  display: block;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(40px, 7vw, 60px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--ice);
}

.page-about .team-cell--lead .team-num {
  color: var(--neon);
}

.page-about .team-role {
  margin: 12px 0 8px;
  font-size: 17px;
  color: var(--ice);
}

.page-about .team-cell p {
  margin: 0;
  max-width: 30em;
  font-size: 15px;
  line-height: 1.75;
  color: var(--mist);
}

.page-about .team-cell[data-reveal]:nth-child(2) {
  transition-delay: 90ms;
}

.page-about .team-cell[data-reveal]:nth-child(3) {
  transition-delay: 180ms;
}

.page-about .about-team-fig {
  margin: 28px 0 0;
}

.page-about .about-team-fig img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 10 / 7;
  object-fit: cover;
  border-radius: var(--r-card);
  border: 1px solid var(--line);
  background: linear-gradient(140deg, var(--deep), var(--sea) 70%, var(--night));
}

/* 表格 */
.page-about .about-table {
  margin-top: 8px;
}

.page-about .about-table th,
.page-about .about-table td {
  font-size: 15px;
  line-height: 1.7;
}

.page-about .about-table tbody th {
  font-weight: 500;
  color: var(--ice);
  white-space: nowrap;
}

.page-about .about-table tbody td {
  color: var(--mist);
}

/* 行内链接 */
.page-about .about-inline-link {
  margin-top: 22px !important;
}

.page-about .about-text-link {
  display: inline-block;
  position: relative;
  color: var(--neon);
  font-size: 16px;
  text-decoration: none;
  padding-bottom: 2px;
}

.page-about .about-text-link::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 1px;
  background: currentColor;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 160ms var(--ease);
}

.page-about .about-text-link:hover::after,
.page-about .about-text-link:focus-visible::after {
  transform: scaleX(1);
}

/* 上手路径 */
.page-about .about-steps {
  margin-top: 8px;
}

.page-about .about-steps .step {
  background: var(--deep);
  border: 1px solid var(--line);
  border-radius: var(--r-card);
  padding: 20px 22px;
  transition: border-color 200ms var(--ease), transform 120ms var(--ease);
}

.page-about .about-steps .step:hover {
  border-color: rgba(75, 240, 206, 0.6);
  transform: translateY(-2px);
}

.page-about .about-steps .step-title {
  font-size: 17px;
  color: var(--ice);
}

.page-about .about-steps .step-text {
  color: var(--mist);
  font-size: 15px;
  line-height: 1.75;
}

/* 结尾 CTA */
.page-about .about-cta {
  margin-top: 36px;
  padding: 28px 26px;
  border-radius: var(--r-card);
  border: 1px solid var(--line);
  background:
    radial-gradient(120% 140% at 100% 0%, rgba(138, 107, 255, 0.22), transparent 58%),
    radial-gradient(120% 140% at 0% 100%, rgba(75, 240, 206, 0.16), transparent 60%),
    var(--deep);
}

.page-about .about-cta-text {
  margin: 0 0 20px;
  max-width: 32em;
  font-size: 17px;
  line-height: 1.75;
  color: var(--ice);
}

.page-about .about-cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: 0;
}

/* 桌面布局 */
@media (min-width: 760px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-side) minmax(0, 1fr);
  }

  .page-about .about-toc {
    align-self: start;
    position: sticky;
    top: var(--about-sticky);
  }

  .page-about .about-toc-list {
    flex-direction: column;
    gap: 2px;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .about-toc-list a {
    border: 0;
    border-left: 1px solid var(--line);
    border-radius: 0;
    padding: 10px 12px;
    font-size: 15px;
  }

  .page-about .about-toc-list a:hover,
  .page-about .about-toc-list a:focus-visible {
    background: transparent;
    border-left-color: var(--neon);
  }

  .page-about .about-split {
    grid-template-columns: 7fr 5fr;
    align-items: start;
    gap: 36px;
  }

  .page-about .team-grid {
    grid-template-columns: 1.35fr 1fr 1fr;
    gap: 18px;
  }

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

@media (min-width: 820px) {
  .page-about {
    --tl-line-x: 120px;
    --tl-pad: 152px;
  }

  .page-about .tl-year {
    position: absolute;
    left: 0;
    top: 0;
    width: 96px;
    margin: 0;
    text-align: right;
    font-size: 46px;
  }

  .page-about .tl-dot {
    top: 14px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .team-cell,
  .page-about .about-steps .step,
  .page-about .tl-dot,
  .page-about .tl-year,
  .page-about .about-text-link::after {
    transition: none;
  }

  .page-about .team-cell:hover,
  .page-about .about-steps .step:hover {
    transform: none;
  }
}