.page-about {
  --about-toc-w: 220px;
  background: var(--ink);
  color: var(--paper);
}

.page-about .breadcrumb {
  padding-block: 20px 0;
  font-size: 13px;
  color: var(--fog);
}

.page-about .breadcrumb-link {
  color: var(--fog);
  text-decoration: none;
  transition: color 160ms var(--ease);
}
.page-about .breadcrumb-link:hover { color: var(--amber); }

.page-about .breadcrumb-current { color: var(--paper); }

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  gap: 30px;
  padding-block: clamp(24px, 4vw, 44px) clamp(36px, 5vw, 66px);
}

.page-about .about-hero-main .label {
  display: inline-block;
  color: var(--gold);
}

.page-about .about-hero h1 {
  font-family: var(--font-display);
  font-size: clamp(30px, 5.4vw, 52px);
  line-height: 1.18;
  letter-spacing: -0.01em;
  font-weight: 700;
  margin: 14px 0 20px;
  max-width: 15em;
}

.page-about .about-lede {
  font-family: var(--font-body);
  font-size: clamp(16px, 1.6vw, 17px);
  line-height: 1.85;
  color: var(--paper);
  max-width: 38em;
  margin: 0 0 26px;
}

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

.page-about .about-facts {
  border: 1px solid var(--line);
  border-top: 2px solid var(--gold);
  background: var(--deep);
  padding: 20px 20px 6px;
}

.page-about .about-facts .label { color: var(--gold); }

.page-about .fact-list {
  list-style: none;
  margin: 12px 0 0;
  padding: 0;
}

.page-about .fact-item {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px;
  padding: 11px 0;
  border-bottom: 1px solid var(--line);
}
.page-about .fact-item:last-child { border-bottom: 0; }

.page-about .fact-key {
  font-family: var(--font-body);
  font-size: 13.5px;
  color: var(--fog);
}

.page-about .fact-val {
  font-family: var(--font-mono);
  font-size: 14.5px;
  letter-spacing: 0.04em;
  color: var(--amber);
  white-space: nowrap;
}

/* ---------- 章节流布局 ---------- */
.page-about .about-layout {
  display: grid;
  gap: 28px;
  border-top: 1px solid var(--line);
  padding-block: clamp(26px, 4vw, 42px) clamp(44px, 6vw, 84px);
}

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

.page-about .about-toc .label { color: var(--gold); }

.page-about .toc {
  list-style: none;
  margin: 12px 0 0;
  padding: 0;
  border-left: 1px solid var(--line);
}

.page-about .toc-link {
  display: block;
  margin-left: -1px;
  padding: 9px 0 9px 15px;
  border-left: 1px solid transparent;
  color: var(--fog);
  font-size: 13.5px;
  line-height: 1.5;
  text-decoration: none;
  transition: color 160ms var(--ease), border-color 160ms var(--ease);
}

.page-about .toc-link:hover,
.page-about .toc-link[aria-current="true"] {
  color: var(--amber);
  border-left-color: var(--amber);
}

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

.page-about .about-chapter {
  border-top: 1px solid var(--line);
  padding-block: clamp(26px, 3.6vw, 42px);
}
.page-about .about-chapter:first-child {
  border-top: 0;
  padding-top: 0;
}

.page-about .ch-head {
  display: flex;
  gap: 14px;
  align-items: baseline;
  margin-bottom: 18px;
}

.page-about .chapter-no {
  flex: none;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.12em;
  color: var(--gold);
  padding-top: 3px;
}

.page-about .ch-head h2 {
  font-family: var(--font-display);
  font-size: clamp(21px, 2.7vw, 30px);
  line-height: 1.25;
  letter-spacing: -0.01em;
  margin: 0;
}

.page-about .ch-lede {
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.8;
  color: var(--fog);
  margin: 8px 0 0;
}

/* ---------- 图片 ---------- */
.page-about .about-figure {
  margin: 0 0 26px;
  border: 1px solid var(--line);
  background: var(--deep);
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: 240px;
  object-fit: cover;
  filter: saturate(0.82) brightness(0.9);
}

.page-about .about-figure figcaption {
  border-top: 1px solid var(--line);
  padding: 10px 14px;
  font-family: var(--font-body);
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--fog);
}

.page-about .about-figure--side { margin-bottom: 0; }
.page-about .about-figure--side img { height: 280px; }

.page-about .about-figure--small { margin: 24px 0 0; }
.page-about .about-figure--small img { height: 200px; }

/* ---------- 时间线 ---------- */
.page-about .timeline {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
}

.page-about .tl-item {
  position: relative;
  display: grid;
  grid-template-columns: 62px minmax(0, 1fr);
  column-gap: 18px;
  padding-bottom: 26px;
}
.page-about .tl-item:last-child { padding-bottom: 0; }

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: 61px;
  top: 12px;
  bottom: 0;
  width: 1px;
  background: var(--line);
}
.page-about .tl-item:last-child::before {
  bottom: auto;
  height: 12px;
}

.page-about .tl-year {
  position: relative;
  font-family: var(--font-mono);
  font-size: 16px;
  line-height: 1.6;
  letter-spacing: 0.04em;
  color: var(--amber);
  text-align: right;
  padding-right: 14px;
}

.page-about .tl-year::before {
  content: "";
  position: absolute;
  right: 0;
  top: 11px;
  width: 9px;
  height: 1px;
  background: var(--gold);
}

.page-about .tl-body h3 {
  font-family: var(--font-display);
  font-size: 17px;
  line-height: 1.4;
  margin: 0 0 6px;
  color: var(--paper);
  transition: color 160ms var(--ease);
}

.page-about .tl-item:hover .tl-body h3 { color: var(--amber); }

.page-about .tl-body p {
  margin: 0;
  font-family: var(--font-body);
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--fog);
}

/* ---------- 校对流程 ---------- */
.page-about .proof-wrap {
  display: grid;
  gap: 24px;
  margin-top: 20px;
}

.page-about .proof-steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 20px;
}

.page-about .proof-step {
  border-left: 1px solid var(--line);
  padding-left: 16px;
}

.page-about .proof-step .label {
  color: var(--gold);
  margin: 0 0 6px;
}

.page-about .proof-step h3 {
  font-family: var(--font-display);
  font-size: 17px;
  line-height: 1.4;
  margin: 0 0 4px;
}

.page-about .proof-bar {
  height: 3px;
  background: var(--line);
  margin: 10px 0 10px;
  overflow: hidden;
}

.page-about .proof-bar span {
  display: block;
  height: 100%;
  background: var(--gold);
}

.page-about .proof-step:nth-child(1) .proof-bar span { width: 52%; }
.page-about .proof-step:nth-child(2) .proof-bar span { width: 34%; }
.page-about .proof-step:nth-child(3) .proof-bar span { width: 18%; }

.page-about .proof-step p:last-child {
  margin: 0;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.85;
  color: var(--fog);
}

/* ---------- 十二类 ---------- */
.page-about .cat-wrap {
  display: grid;
  gap: 24px;
  margin-top: 20px;
}

.page-about .cat-ring-box {
  display: flex;
  justify-content: center;
}

.page-about .cat-ring {
  width: 100%;
  max-width: 230px;
  height: auto;
}

.page-about .cat-ring text {
  fill: var(--gold);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
}

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

.page-about .cat-item {
  display: flex;
  align-items: baseline;
  gap: 8px;
  background: var(--ink);
  padding: 11px 12px;
  transition: background 160ms var(--ease);
}

.page-about .cat-item:hover { background: var(--night); }

.page-about .cat-no {
  flex: none;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--gold);
}

.page-about .cat-name {
  font-family: var(--font-body);
  font-size: 14px;
  color: var(--paper);
}

.page-about .cat-notes {
  margin-top: 22px;
  padding-left: 14px;
  border-left: 2px solid var(--wine);
}

.page-about .cat-notes p {
  margin: 0 0 12px;
  font-family: var(--font-body);
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--fog);
}
.page-about .cat-notes p:last-child { margin-bottom: 0; }

/* ---------- 后两章并列 ---------- */
.page-about .closing-grid {
  display: grid;
  gap: 0;
}

.page-about .srv-grid {
  display: grid;
  gap: 14px;
  margin-bottom: 20px;
}

.page-about .srv-card {
  border: 1px solid var(--line);
  background: var(--deep);
  padding: 16px 16px 18px;
}

.page-about .srv-big {
  font-family: var(--font-mono);
  font-size: clamp(22px, 3vw, 27px);
  letter-spacing: 0.02em;
  color: var(--amber);
  margin: 0 0 4px;
  line-height: 1.2;
}

.page-about .srv-card .label {
  color: var(--gold);
  margin: 0 0 10px;
}

.page-about .srv-card p:last-child {
  margin: 0;
  font-family: var(--font-body);
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--fog);
}

.page-about .ch-tail {
  margin: 0;
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.85;
  color: var(--fog);
}

.page-about .inline-link {
  color: var(--amber);
  text-decoration: none;
  border-bottom: 1px solid rgba(227, 166, 90, 0.4);
  transition: border-color 160ms var(--ease);
}
.page-about .inline-link:hover { border-bottom-color: var(--amber); }

.page-about .rhythm-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .rhythm-item {
  display: grid;
  grid-template-columns: 64px minmax(0, 1fr);
  gap: 12px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--line);
}
.page-about .rhythm-item:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .rhythm-tag {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--moss);
  padding-top: 4px;
}

.page-about .rhythm-item h3 {
  font-family: var(--font-display);
  font-size: 15.5px;
  line-height: 1.4;
  margin: 0 0 5px;
}

.page-about .rhythm-item p {
  margin: 0;
  font-family: var(--font-body);
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--fog);
}

/* ---------- 尾部跳转条 ---------- */
.page-about .next-strip {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 18px 28px;
  border: 1px solid var(--line);
  border-left: 3px solid var(--amber);
  background: var(--deep);
  padding: clamp(20px, 3vw, 30px);
  margin-bottom: clamp(46px, 6vw, 80px);
}

.page-about .next-strip .label { color: var(--gold); }

.page-about .next-strip h2 {
  font-family: var(--font-display);
  font-size: clamp(19px, 2.4vw, 24px);
  line-height: 1.3;
  margin: 8px 0 8px;
}

.page-about .next-strip p:last-child {
  margin: 0;
  max-width: 42em;
  font-family: var(--font-body);
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--fog);
}

/* ---------- 断点 ---------- */
@media (min-width: 640px) {
  .page-about .about-figure img { height: 300px; }
  .page-about .about-figure--side img { height: 320px; }
  .page-about .about-figure--small img { height: 240px; }
  .page-about .cat-list { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .page-about .srv-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (min-width: 860px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.18fr) minmax(0, 0.82fr);
    gap: clamp(30px, 4vw, 64px);
    align-items: start;
  }

  .page-about .proof-wrap {
    grid-template-columns: minmax(0, 1.06fr) minmax(0, 0.94fr);
    gap: 30px;
    align-items: start;
  }

  .page-about .cat-wrap {
    grid-template-columns: 230px minmax(0, 1fr);
    gap: 32px;
    align-items: center;
  }

  .page-about .cat-ring-box { justify-content: flex-start; }

  .page-about .closing-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: clamp(24px, 3.4vw, 44px);
    border-top: 1px solid var(--line);
  }

  .page-about .closing-grid .about-chapter {
    border-top: 0;
    padding-top: clamp(26px, 3.6vw, 42px);
  }
}

@media (min-width: 960px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-toc-w) minmax(0, 1fr);
    gap: clamp(32px, 4vw, 60px);
    align-items: start;
  }

  .page-about .about-toc {
    display: block;
    position: sticky;
    top: calc(var(--header-h) + 24px);
  }
}

@media (min-width: 1100px) {
  .page-about .about-figure img { height: 320px; }
  .page-about .about-figure--side img { height: 340px; }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .toc-link,
  .page-about .tl-body h3,
  .page-about .cat-item,
  .page-about .inline-link {
    transition: none;
  }
}