.page-about {
  --about-rail: clamp(52px, 10vw, 118px);
  --about-pad: clamp(40px, 6.6vw, 84px);
  color: var(--paper);
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumbs {
  padding-top: clamp(14px, 2.4vw, 22px);
  font-size: 12px;
  letter-spacing: .04em;
}

.page-about .breadcrumbs ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  color: var(--text-faint);
}

.page-about .breadcrumbs li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--hairline-strong);
}

.page-about .breadcrumbs a {
  color: var(--cyan-soft);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color .2s var(--ease);
}

.page-about .breadcrumbs a:hover,
.page-about .breadcrumbs a:focus-visible {
  border-bottom-color: var(--cyan);
}

.page-about .breadcrumbs [aria-current="page"] {
  color: var(--text-muted);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(22px, 4vw, 46px) 0 clamp(28px, 4.6vw, 56px);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background: var(--hairline);
}

.page-about .about-hero-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(24px, 3.6vw, 44px);
}

.page-about .about-hero h1 {
  margin: 14px 0 0;
  max-width: 20ch;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(29px, 6.6vw, 52px);
  line-height: 1.08;
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .about-hero-lead {
  margin: 18px 0 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.72;
  color: var(--text-muted);
}

.page-about .about-hero-actions {
  margin-top: clamp(22px, 3vw, 30px);
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .about-hero-aside {
  position: relative;
  padding: clamp(18px, 3vw, 26px);
  border: 1px solid var(--hairline);
  border-radius: var(--radius);
  background: var(--glass);
  box-shadow: var(--shadow-card);
}

.page-about .about-hero-aside::before {
  content: "";
  position: absolute;
  top: 0;
  left: clamp(18px, 3vw, 26px);
  width: 44px;
  height: 3px;
  background: var(--cyan);
  border-radius: 0 0 2px 2px;
}

.page-about .about-aside-label {
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--cyan-soft);
}

.page-about .about-facts {
  margin: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-fact {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px;
  padding-bottom: 12px;
  border-bottom: 1px dashed var(--hairline);
}

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

.page-about .about-fact dt {
  font-size: 13px;
  color: var(--text-faint);
}

.page-about .about-fact dd {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(20px, 3vw, 24px);
  font-weight: 700;
  line-height: 1;
  color: var(--cyan);
  font-variant-numeric: tabular-nums;
}

.page-about .about-aside-note {
  margin: 18px 0 0;
  padding-top: 14px;
  border-top: 1px solid var(--hairline);
  font-size: 12px;
  line-height: 1.7;
  color: var(--text-faint);
}

/* ---------- 页内目录 ---------- */
.page-about .about-jump {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding: clamp(14px, 2.4vw, 20px) 0 clamp(16px, 2.6vw, 24px);
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}

.page-about .about-jump::-webkit-scrollbar {
  display: none;
}

.page-about .about-jump a {
  flex: 0 0 auto;
  scroll-snap-align: start;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 44px;
  padding: 0 15px;
  border: 1px solid var(--hairline);
  border-radius: var(--radius-pill);
  background: rgba(18, 49, 41, .55);
  color: var(--text-muted);
  font-size: 13px;
  text-decoration: none;
  white-space: nowrap;
  transition: color .2s var(--ease), border-color .2s var(--ease), background .2s var(--ease);
}

.page-about .about-jump a:hover,
.page-about .about-jump a:focus-visible {
  color: var(--paper);
  border-color: var(--hairline-strong);
  background: var(--panel);
}

.page-about .about-jump-index {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--cyan);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-chapter {
  position: relative;
  padding: var(--about-pad) 0;
  border-top: 3px solid var(--stone);
  scroll-margin-top: 20px;
}

.page-about .about-chapter--moss { border-top-color: var(--moss); }
.page-about .about-chapter--clay { border-top-color: var(--clay); }
.page-about .about-chapter--stone { border-top-color: var(--stone); }

.page-about .about-chapter-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(14px, 2.6vw, 22px);
}

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

.page-about .about-rail-index {
  font-family: var(--font-mono);
  font-size: clamp(26px, 5vw, 40px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: rgba(243, 239, 230, .22);
  font-variant-numeric: tabular-nums;
  transition: color .3s var(--ease);
}

.page-about .about-chapter.is-active .about-rail-index {
  color: var(--cyan);
}

.page-about .about-rail-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--text-faint);
}

.page-about .about-chapter-body {
  min-width: 0;
}

.page-about .about-chapter-body .section-title {
  margin: 0 0 14px;
}

.page-about .about-lead {
  margin: 0 0 16px;
  max-width: 64ch;
  font-size: 15px;
  line-height: 1.72;
  color: var(--cyan-soft);
}

.page-about .about-text {
  margin: 0 0 14px;
  max-width: 68ch;
  font-size: 15px;
  line-height: 1.72;
  color: var(--text-muted);
}

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

/* ---------- 起点清单 ---------- */
.page-about .about-points {
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 12px;
}

.page-about .about-points li {
  padding: 14px 16px;
  border-left: 2px solid var(--moss);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  background: rgba(18, 49, 41, .5);
  font-size: 14px;
  line-height: 1.66;
  color: var(--text-muted);
}

.page-about .about-points-key {
  display: block;
  margin-bottom: 4px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--cyan-soft);
}

/* ---------- 图文分区 ---------- */
.page-about .about-split {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(22px, 3.4vw, 38px);
}

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

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

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border: 1px solid var(--hairline);
  border-radius: var(--radius);
  object-fit: cover;
  background: var(--panel);
}

.page-about .about-figure--tall img {
  aspect-ratio: 4 / 3;
}

.page-about .about-figure--wide img {
  aspect-ratio: 16 / 9;
}

.page-about .about-figure .media-caption {
  margin-top: 10px;
  font-size: 12px;
  line-height: 1.7;
  color: var(--text-faint);
}

/* ---------- 团队角色 ---------- */
.page-about .about-roles {
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

.page-about .about-role {
  position: relative;
  padding: 18px 18px 20px;
  border: 1px solid var(--hairline);
  border-radius: var(--radius);
  background: var(--panel);
  transition: transform .22s var(--ease), border-color .22s var(--ease), background .22s var(--ease);
}

.page-about .about-role-title {
  margin: 12px 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 18px;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .about-role-text {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-muted);
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  margin: 28px 0 0;
  padding: 0 0 0 18px;
  list-style: none;
  position: relative;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  top: 6px;
  bottom: 6px;
  left: 4px;
  width: 2px;
  background: linear-gradient(180deg, var(--cyan), var(--moss) 55%, rgba(180, 113, 78, .55));
  opacity: .5;
}

.page-about .about-tl-item {
  position: relative;
  margin-bottom: 12px;
}

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

.page-about .about-tl-item::before {
  content: "";
  position: absolute;
  top: 20px;
  left: -18px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--ink);
  border: 2px solid var(--cyan);
  transform: translateX(-4px);
}

.page-about .about-tl-item:not(:first-child)::before {
  border-color: var(--moss);
}

.page-about .about-node {
  border: 1px solid var(--hairline);
  border-radius: var(--radius-sm);
  background: rgba(18, 49, 41, .55);
  overflow: hidden;
}

.page-about .about-node-head {
  display: flex;
  align-items: center;
  gap: 12px;
  min-height: 52px;
  padding: 12px 16px;
  cursor: pointer;
  list-style: none;
}

.page-about .about-node-head::-webkit-details-marker {
  display: none;
}

.page-about .about-node-index {
  flex: 0 0 auto;
  font-size: 13px;
  font-weight: 700;
  color: var(--cyan);
}

.page-about .about-node-title {
  flex: 1 1 auto;
  min-width: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 16px;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .about-node-meta {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--text-faint);
}

.page-about .about-node-body {
  padding: 0 16px 16px;
  border-top: 1px solid var(--hairline);
}

.page-about .about-node-body p {
  margin: 14px 0 0;
  max-width: 62ch;
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-muted);
}

/* ---------- 覆盖数据 ---------- */
.page-about .about-stats {
  margin: 26px 0 22px;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.page-about .about-stat {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 16px 14px;
  border: 1px solid var(--hairline);
  border-radius: var(--radius-sm);
  background: var(--panel-2);
}

.page-about .about-stat-num {
  font-size: clamp(22px, 4vw, 30px);
  font-weight: 700;
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-stat-label {
  font-size: 13px;
  line-height: 1.5;
  color: var(--paper);
}

.page-about .about-stat-note {
  margin-top: auto;
  font-size: 11px;
  line-height: 1.6;
  color: var(--text-faint);
}

/* ---------- 三条原则 ---------- */
.page-about .about-rules {
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 16px;
  counter-reset: none;
}

.page-about .about-rule {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: 14px;
  padding: 18px 16px;
  border: 1px solid var(--hairline);
  border-left: 3px solid var(--clay);
  border-radius: var(--radius-sm);
  background: rgba(18, 49, 41, .5);
}

.page-about .about-rule-index {
  font-size: 26px;
  font-weight: 700;
  line-height: 1;
  color: var(--clay);
}

.page-about .about-rule-title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 17px;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .about-rule-text {
  margin: 0;
  max-width: 62ch;
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-muted);
}

/* ---------- 收尾 ---------- */
.page-about .about-outro {
  padding: clamp(38px, 6vw, 72px) 0 clamp(48px, 7vw, 88px);
  border-top: 3px solid var(--cyan);
  background: linear-gradient(180deg, rgba(47, 230, 200, .06), transparent 60%);
}

.page-about .about-outro-inner {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
}

.page-about .about-outro .section-title {
  margin: 0 0 14px;
}

.page-about .about-outro-text {
  margin: 0;
  max-width: 64ch;
  font-size: 15px;
  line-height: 1.72;
  color: var(--text-muted);
}

.page-about .about-outro-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-content: start;
}

/* ---------- 桌面端 ---------- */
@media (min-width: 640px) {
  .page-about .about-roles {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
  }

  .page-about .about-stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 14px;
  }
}

@media (min-width: 860px) {
  .page-about .about-chapter-grid {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: clamp(26px, 4vw, 60px);
  }

  .page-about .about-rail {
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero-grid {
    grid-template-columns: 7fr 5fr;
    align-items: start;
    gap: clamp(30px, 4.5vw, 56px);
  }

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

  .page-about .about-outro-inner {
    grid-template-columns: 8fr 4fr;
    align-items: end;
    gap: 32px;
  }

  .page-about .about-role:hover {
    transform: translateY(-2px);
    border-color: var(--hairline-strong);
    background: var(--panel-2);
  }

  .page-about .about-stat:hover {
    border-color: var(--hairline-strong);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-role,
  .page-about .about-rail-index,
  .page-about .about-jump a {
    transition: none;
  }

  .page-about .about-role:hover {
    transform: none;
  }
}