.page-about {
  --about-gap: clamp(20px, 3.5vw, 48px);
  --about-note-bg: rgba(13, 31, 51, 0.74);
  --about-text: rgba(233, 242, 245, 0.84);
  --about-text-soft: rgba(233, 242, 245, 0.7);
}

.page-about .about-crumbs {
  padding-block: clamp(12px, 2vw, 20px) 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-masthead {
  display: grid;
  gap: var(--about-gap);
  padding-block: clamp(22px, 4vw, 46px) clamp(28px, 4vw, 54px);
  border-bottom: 1px solid var(--line);
}

.page-about .masthead-copy {
  display: grid;
  gap: 16px;
  align-content: end;
}

.page-about .masthead-tag {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--cyan);
}

.page-about .masthead-tag::before {
  content: "";
  width: 28px;
  height: 2px;
  background: linear-gradient(90deg, var(--cyan), var(--gold));
}

.page-about h1 {
  margin: 0;
  max-width: 16ch;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(32px, 6.2vw, 72px);
  line-height: 1.04;
  letter-spacing: -0.035em;
  color: var(--paper);
}

.page-about .about-lede {
  margin: 0;
  max-width: 62ch;
  font-size: clamp(15px, 1.6vw, 18px);
  line-height: 1.8;
  color: var(--about-text);
}

.page-about .masthead-visual {
  margin: 0;
  clip-path: var(--chamfer-panel);
  background: linear-gradient(150deg, var(--console), var(--deep-teal) 60%, var(--wine));
}

.page-about .masthead-visual img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

@media (min-width: 900px) {
  .page-about .about-masthead {
    grid-template-columns: minmax(0, 1.06fr) minmax(0, 0.94fr);
    align-items: end;
  }
}

/* ---------- 主结构 ---------- */
.page-about .about-ledger {
  display: grid;
  gap: var(--about-gap);
  padding-block: clamp(26px, 4vw, 52px) 0;
}

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

.page-about .ledger-rail li {
  flex: 0 0 auto;
}

.page-about .rail-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  white-space: nowrap;
  text-decoration: none;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--about-text-soft);
  background: rgba(13, 31, 51, 0.6);
  box-shadow: inset 0 0 0 1px var(--line);
  clip-path: var(--chamfer-btn);
  transition: color var(--fast) var(--ease), background var(--fast) var(--ease), box-shadow var(--fast) var(--ease);
}

.page-about .rail-link em {
  font-style: normal;
  color: var(--cyan);
}

.page-about .rail-link:hover,
.page-about .rail-link:focus-visible {
  color: var(--paper);
  background: rgba(77, 227, 224, 0.14);
  box-shadow: inset 0 0 0 1px var(--cyan);
}

@media (min-width: 1024px) {
  .page-about .about-ledger {
    grid-template-columns: 178px minmax(0, 1fr);
    column-gap: clamp(28px, 4vw, 60px);
  }

  .page-about .ledger-rail {
    position: sticky;
    top: 96px;
    align-self: start;
  }

  .page-about .ledger-rail ol {
    flex-direction: column;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .rail-link {
    width: 100%;
  }
}

/* ---------- 章节 ---------- */
.page-about .chapter {
  padding-block: clamp(24px, 3.4vw, 42px);
  border-top: 1px solid var(--line);
  scroll-margin-top: 92px;
}

.page-about .chapter:first-of-type {
  border-top: 0;
  padding-top: 0;
}

.page-about .chapter-head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: clamp(12px, 2vw, 26px);
  align-items: end;
  margin-bottom: clamp(14px, 2vw, 22px);
}

.page-about .chapter-no {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(44px, 8vw, 104px);
  line-height: 0.78;
  letter-spacing: -0.05em;
  color: rgba(233, 242, 245, 0.1);
  -webkit-text-stroke: 1px rgba(77, 227, 224, 0.42);
}

.page-about .chapter-title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(20px, 3vw, 32px);
  line-height: 1.28;
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .chapter-kicker {
  display: block;
  margin-top: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--gold);
}

.page-about .chapter-body {
  display: grid;
  gap: clamp(16px, 2.5vw, 30px);
}

@media (min-width: 780px) {
  .page-about .chapter-body {
    grid-template-columns: minmax(0, 1fr) 236px;
    align-items: start;
  }

  .page-about #chapter-library .chapter-body,
  .page-about #chapter-cadence .chapter-body {
    grid-template-columns: minmax(0, 1fr);
  }
}

.page-about .chapter-main p {
  margin: 0 0 14px;
  max-width: 64ch;
  font-size: clamp(15px, 1.55vw, 17px);
  line-height: 1.85;
  color: var(--about-text);
}

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

.page-about .chapter-main a {
  color: var(--cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
}

.page-about .chapter-main a:hover,
.page-about .chapter-main a:focus-visible {
  color: var(--ice);
}

/* ---------- 边注 ---------- */
.page-about .chapter-note {
  padding: 16px 16px 18px;
  background: var(--about-note-bg);
  border-left: 2px solid var(--cyan);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 18px), calc(100% - 18px) 100%, 0 100%);
}

.page-about .chapter-note--wine {
  background: linear-gradient(165deg, rgba(74, 31, 61, 0.6), rgba(7, 17, 31, 0.86));
  border-left-color: var(--gold);
}

.page-about .note-label {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--cyan);
}

.page-about .chapter-note--wine .note-label {
  color: var(--gold);
}

.page-about .note-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 8px;
}

.page-about .note-list li {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
  padding-bottom: 8px;
  border-bottom: 1px dashed rgba(39, 68, 90, 0.9);
  font-family: var(--font-mono);
  font-size: 12.5px;
  line-height: 1.5;
  color: var(--about-text-soft);
}

.page-about .note-list li:last-child {
  padding-bottom: 0;
  border-bottom: 0;
}

.page-about .note-list b {
  flex: 0 0 auto;
  font-weight: 600;
  color: var(--gold);
}

/* ---------- 图片 ---------- */
.page-about .library-visual {
  margin: 0;
  clip-path: var(--chamfer-panel);
  background: linear-gradient(160deg, var(--deep-teal), var(--console));
}

.page-about .library-visual img,
.page-about .cadence-figure img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.page-about .library-visual img {
  max-width: 100%;
  height: auto;
}

@media (min-width: 780px) {
  .page-about .library-visual {
    max-width: 100%;
  }
}

.page-about .cadence-figure {
  margin: clamp(16px, 2.5vw, 26px) 0;
  clip-path: var(--chamfer-panel);
  background: linear-gradient(160deg, var(--console), var(--deep-teal));
}

.page-about .cadence-figure img {
  max-width: 100%;
  height: auto;
}

/* ---------- 更新节奏轨道 ---------- */
.page-about .cadence-track {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 12px;
}

@media (min-width: 860px) {
  .page-about .cadence-track {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .cadence-node {
  padding: 18px 18px 18px 22px;
  background: linear-gradient(160deg, rgba(13, 31, 51, 0.96), rgba(11, 43, 51, 0.84));
  clip-path: var(--chamfer-btn);
  box-shadow: inset 0 0 0 1px rgba(39, 68, 90, 0.9);
  transition: transform var(--fast) var(--ease), box-shadow var(--fast) var(--ease), background var(--fast) var(--ease);
}

.page-about .cadence-node:hover,
.page-about .cadence-node:focus-visible {
  transform: translateY(-2px);
  background: linear-gradient(160deg, rgba(77, 227, 224, 0.16), rgba(11, 43, 51, 0.92));
  box-shadow: inset 0 0 0 1px var(--cyan);
  outline: none;
}

.page-about .node-dot {
  display: block;
  width: 10px;
  height: 10px;
  margin-bottom: 12px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 4px rgba(77, 227, 224, 0.16), 0 0 14px rgba(77, 227, 224, 0.5);
}

.page-about .node-when {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--gold);
}

.page-about .node-title {
  display: block;
  margin-top: 6px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 16px;
  color: var(--paper);
}

.page-about .node-note {
  display: block;
  margin-top: 8px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--about-text-soft);
}

/* ---------- 团队 ---------- */
.page-about .role-grid {
  margin: 6px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 12px;
}

@media (min-width: 720px) {
  .page-about .role-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

.page-about .role-card {
  padding: 18px 18px 20px;
  background: linear-gradient(170deg, rgba(74, 31, 61, 0.58), rgba(7, 17, 31, 0.88));
  clip-path: var(--chamfer-btn);
  box-shadow: inset 0 0 0 1px rgba(246, 196, 83, 0.24);
  transition: transform var(--fast) var(--ease), box-shadow var(--fast) var(--ease);
}

.page-about .role-card:hover,
.page-about .role-card:focus-within {
  transform: translateY(-2px);
  box-shadow: inset 0 0 0 1px var(--gold);
}

.page-about .role-count {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 20px;
  letter-spacing: 0.02em;
  color: var(--gold);
}

.page-about .role-card h3 {
  margin: 8px 0 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 17px;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .role-card p {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.72;
  color: var(--about-text-soft);
  max-width: none;
}

/* ---------- 收尾 ---------- */
.page-about .about-cta {
  display: grid;
  gap: 18px;
  margin-top: clamp(26px, 4vw, 46px);
  padding: clamp(22px, 3vw, 34px);
  clip-path: var(--chamfer-panel);
  background: linear-gradient(120deg, var(--deep-teal), var(--console) 55%, var(--wine));
  box-shadow: inset 0 0 0 1px rgba(77, 227, 224, 0.18);
}

.page-about .about-cta h2 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(20px, 2.6vw, 28px);
  line-height: 1.3;
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .about-cta p {
  margin: 0;
  max-width: 58ch;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--about-text-soft);
}

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

@media (min-width: 820px) {
  .page-about .about-cta {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .cadence-node,
  .page-about .role-card,
  .page-about .rail-link {
    transition: none;
  }

  .page-about .cadence-node:hover,
  .page-about .cadence-node:focus-visible,
  .page-about .role-card:hover,
  .page-about .role-card:focus-within {
    transform: none;
  }

  .page-about .node-dot {
    box-shadow: 0 0 0 4px rgba(77, 227, 224, 0.16);
  }
}
<<<END>>>