.page-about {
  --about-rail: clamp(56px, 9vw, 110px);
  --about-gap: clamp(20px, 3vw, 44px);
  --about-rule: rgba(122, 134, 168, 0.28);
  --about-rule-soft: rgba(122, 134, 168, 0.16);
  display: block;
  overflow-wrap: break-word;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  grid-template-columns: 1fr;
  gap: 22px;
  padding: clamp(28px, 4vw, 52px) 0 clamp(40px, 5vw, 76px);
  border-bottom: 1px solid var(--about-rule);
}

.page-about .about-hero-rail {
  display: flex;
  align-items: baseline;
  gap: 14px;
}

.page-about .about-hero-num {
  font-family: var(--font-display);
  font-size: clamp(62px, 13vw, 132px);
  font-weight: 800;
  line-height: 0.82;
  letter-spacing: -0.03em;
  color: var(--red);
}

.page-about .about-hero-anno {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.24em;
  color: var(--grid);
  white-space: nowrap;
}

.page-about .about-kicker {
  margin: 0 0 18px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.26em;
  color: var(--cyan);
}

.page-about .about-hero-copy h1 {
  margin: 0 0 20px;
  font-family: var(--font-heading);
  font-size: clamp(29px, 5vw, 52px);
  font-weight: 700;
  line-height: 1.14;
  letter-spacing: -0.01em;
  color: var(--white);
}

.page-about .about-lead {
  margin: 0;
  max-width: 34em;
  font-size: clamp(16px, 1.5vw, 17px);
  line-height: 1.85;
  color: var(--silver);
}

.page-about .about-index {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 30px;
}

.page-about .about-index .chip {
  text-decoration: none;
  transition: background-color var(--dur) var(--ease), color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .about-index .chip .num {
  margin-right: 7px;
  opacity: 0.75;
  font-size: 12px;
}

.page-about .about-index .chip:hover {
  border-color: var(--cyan);
  color: var(--white);
}

.page-about .about-stats {
  list-style: none;
  margin: 34px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--about-rule);
  border: 1px solid var(--about-rule);
  border-radius: var(--r-md);
  overflow: hidden;
}

.page-about .about-stats .stat {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 16px 18px 18px;
  background: var(--void);
}

.page-about .about-stats .stat-value {
  font-family: var(--font-display);
  font-size: clamp(24px, 3vw, 32px);
  font-weight: 800;
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--white);
}

.page-about .about-stats .stat-label {
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--grid);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-chapters {
  display: block;
}

.page-about .chapter {
  display: grid;
  grid-template-columns: 1fr;
  gap: 18px;
  padding: clamp(40px, 6vw, 84px) 0;
  border-bottom: 1px solid var(--about-rule-soft);
  scroll-margin-top: 96px;
}

.page-about .chapter-rail {
  display: flex;
  align-items: baseline;
  gap: 14px;
}

.page-about .chapter-idx {
  font-family: var(--font-display);
  font-size: clamp(44px, 7vw, 72px);
  font-weight: 800;
  line-height: 0.9;
  letter-spacing: -0.02em;
  color: var(--red);
  transition: color var(--dur-slow) var(--ease);
}

.page-about .chapter--blue .chapter-idx {
  color: var(--blue-lit);
}

.page-about .chapter-anno {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--grid);
  white-space: nowrap;
}

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

.page-about .chapter-title {
  position: relative;
  display: inline-block;
  margin: 0 0 18px;
  padding-bottom: 12px;
  font-family: var(--font-heading);
  font-size: clamp(22px, 3.4vw, 32px);
  font-weight: 700;
  line-height: 1.26;
  color: var(--white);
  cursor: default;
}

.page-about .chapter-title::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 46px;
  height: 2px;
  background: var(--red);
  transition: width var(--dur-slow) var(--ease), background-color var(--dur-slow) var(--ease);
}

.page-about .chapter--blue .chapter-title::after {
  background: var(--blue);
}

.page-about .chapter-title:hover::after {
  width: 148px;
  background: var(--cyan);
}

.page-about .chapter:has(.chapter-title:hover) .chapter-idx {
  color: var(--cyan);
}

.page-about .chapter-lead {
  margin: 0 0 26px;
  max-width: 34em;
  font-size: 16px;
  line-height: 1.85;
  color: var(--silver);
}

.page-about .chapter-text p,
.page-about .chapter-tail {
  margin: 0 0 16px;
  max-width: 34em;
  font-size: 16px;
  line-height: 1.85;
  color: var(--silver);
}

.page-about .chapter-tail {
  margin-top: 26px;
  padding-top: 20px;
  border-top: 1px solid var(--about-rule-soft);
}

.page-about .chapter-close {
  height: 10px;
  margin-top: 30px;
  background-image: repeating-linear-gradient(
    90deg,
    rgba(122, 134, 168, 0.55) 0,
    rgba(122, 134, 168, 0.55) 1px,
    transparent 1px,
    transparent 12px
  );
  opacity: 0.5;
}

/* ---------- 图形容器 ---------- */
.page-about .chapter-split {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
  align-items: start;
}

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

.page-about .chapter-media .media-frame {
  overflow: hidden;
}

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

.page-about .chapter-media .media-caption {
  margin-top: 12px;
}

/* ---------- 01 时间刻度 ---------- */
.page-about .venue-clock {
  list-style: none;
  margin: 0 0 30px;
  padding: 0;
}

.page-about .clock-row {
  display: grid;
  grid-template-columns: 68px minmax(0, 1fr);
  gap: 16px;
  padding: 14px 0;
  border-top: 1px solid var(--about-rule-soft);
}

.page-about .clock-row:last-child {
  border-bottom: 1px solid var(--about-rule-soft);
}

.page-about .clock-time {
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--cyan);
  padding-top: 2px;
}

.page-about .clock-text {
  font-size: 15px;
  line-height: 1.78;
  color: var(--silver);
}

/* ---------- 02 档案层级 ---------- */
.page-about .archive-tiers {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

.page-about .tier {
  display: flex;
  flex-direction: column;
  gap: 9px;
  padding: 22px 22px 24px;
}

.page-about .tier-idx {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 800;
  letter-spacing: 0.08em;
  color: var(--cyan);
}

.page-about .tier h3 {
  margin: 0;
  font-family: var(--font-heading);
  font-size: 19px;
  font-weight: 600;
  color: var(--white);
}

.page-about .tier p {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--silver);
}

/* ---------- 03 核验流程 ---------- */
.page-about .verify-flow {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
}

.page-about .verify-flow li {
  display: grid;
  grid-template-columns: 78px minmax(0, 1fr);
  gap: 16px;
  align-items: baseline;
  padding: 14px 0;
  border-top: 1px solid var(--about-rule-soft);
}

.page-about .verify-flow li:last-child {
  border-bottom: 1px solid var(--about-rule-soft);
}

.page-about .flow-key {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 800;
  letter-spacing: 0.02em;
  color: var(--red-lit);
}

.page-about .flow-val {
  font-size: 15px;
  line-height: 1.78;
  color: var(--silver);
}

/* ---------- 04 梯队标签 ---------- */
.page-about .tier-chips {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 9px;
  margin: 22px 0 0;
  padding: 0;
}

/* ---------- 05 表达习惯 ---------- */
.page-about .habit-list {
  list-style: none;
  margin: 4px 0 0;
  padding: 0;
}

.page-about .habit-list li {
  display: grid;
  grid-template-columns: 16px minmax(0, 1fr);
  gap: 14px;
  padding: 16px 0;
  border-top: 1px solid var(--about-rule-soft);
}

.page-about .habit-list li:last-child {
  border-bottom: 1px solid var(--about-rule-soft);
}

.page-about .habit-list .dot {
  margin-top: 9px;
}

.page-about .habit-body {
  font-size: 15px;
  line-height: 1.82;
  color: var(--silver);
}

.page-about .habit-body strong {
  color: var(--white);
  font-weight: 600;
}

/* ---------- 去向卡片 ---------- */
.page-about .about-next {
  padding: clamp(56px, 8vw, 104px) 0 clamp(24px, 4vw, 48px);
}

.page-about .about-next-title {
  margin: 0 0 14px;
  font-family: var(--font-heading);
  font-size: clamp(22px, 3vw, 30px);
  font-weight: 700;
  color: var(--white);
}

.page-about .about-next-lead {
  margin: 0 0 32px;
  max-width: 34em;
  font-size: 16px;
  line-height: 1.85;
  color: var(--silver);
}

.page-about .about-next-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

.page-about .next-card {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  grid-template-rows: auto auto;
  column-gap: 18px;
  row-gap: 6px;
  padding: 22px 24px;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background: var(--panel);
  text-decoration: none;
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .next-card:hover,
.page-about .next-card:focus-visible {
  border-color: var(--blue);
}

.page-about .next-card .next-tag {
  grid-row: span 2;
  align-self: start;
  font-family: var(--font-display);
  font-size: 30px;
  font-weight: 800;
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--red);
  transition: color var(--dur) var(--ease);
}

.page-about .next-card:hover .next-tag {
  color: var(--cyan);
}

.page-about .next-label {
  font-family: var(--font-heading);
  font-size: 18px;
  font-weight: 600;
  color: var(--white);
}

.page-about .next-note {
  font-size: 14px;
  line-height: 1.72;
  color: var(--grid);
}

/* ---------- 右侧刻度指示 ---------- */
.page-about .doc-ruler {
  display: none;
}

/* ---------- 响应式 ---------- */
@media (min-width: 620px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-next-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
  }
}

@media (min-width: 760px) {
  .page-about .about-hero {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: var(--about-gap);
  }

  .page-about .about-hero-rail {
    flex-direction: column;
    align-items: flex-start;
    gap: 18px;
    padding-top: 6px;
  }

  .page-about .about-hero-anno {
    writing-mode: vertical-rl;
    letter-spacing: 0.3em;
  }

  .page-about .archive-tiers {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
  }

  .page-about .verify-flow {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: 40px;
  }

  .page-about .verify-flow li:nth-child(2) {
    border-top: 1px solid var(--about-rule-soft);
  }
}

@media (min-width: 900px) {
  .page-about .chapter {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: var(--about-gap);
  }

  .page-about .chapter-rail {
    position: sticky;
    top: 116px;
    flex-direction: column;
    align-items: flex-start;
    gap: 18px;
    align-self: start;
  }

  .page-about .chapter-anno {
    writing-mode: vertical-rl;
    letter-spacing: 0.26em;
    padding-top: 4px;
  }

  .page-about .chapter-split {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.24fr);
    gap: var(--about-gap);
  }

  .page-about .chapter-split--reverse .chapter-media {
    order: -1;
  }
}

@media (min-width: 1200px) {
  .page-about .doc-ruler {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 9px;
    position: fixed;
    top: 50%;
    right: 16px;
    transform: translateY(-50%);
    z-index: 4;
    pointer-events: none;
  }

  .page-about .doc-ruler i {
    display: block;
    width: 12px;
    height: 1px;
    background: var(--grid);
    opacity: 0.32;
  }

  .page-about .doc-ruler i:nth-child(5n + 1) {
    width: 22px;
    opacity: 0.6;
    background: var(--cyan);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .chapter-title::after,
  .page-about .chapter-idx,
  .page-about .next-card,
  .page-about .next-card .next-tag,
  .page-about .about-index .chip {
    transition: none;
  }
}
<<<END>>>