.page-about {
  background: var(--paper-50);
  color: var(--ink-500);
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  line-height: 1.75;
  overflow-x: clip;
}

.page-about .mono {
  font-family: var(--font-mono);
  letter-spacing: 0.08em;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  background: var(--apricot-100);
  border-bottom: var(--border-w) solid var(--ink-900);
  padding: 28px 0 34px;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: radial-gradient(rgba(11, 31, 51, 0.09) 1px, transparent 1px);
  background-size: 18px 18px;
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  right: -110px;
  top: -80px;
  width: 240px;
  height: 240px;
  background: var(--brand-orange-500);
  border-radius: 26px;
  transform: rotate(14deg);
  opacity: 0.9;
  pointer-events: none;
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
  width: min(var(--shell-max), 100% - var(--gutter) * 2);
  margin: 0 auto;
}

.page-about .breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  list-style: none;
  margin: 0 0 18px;
  padding: 0;
  font-size: 0.82rem;
  color: var(--grey-500);
}

.page-about .breadcrumb li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--grey-200);
}

.page-about .breadcrumb a {
  color: var(--ink-700);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.18s var(--ease), color 0.18s var(--ease);
}

.page-about .breadcrumb a:hover,
.page-about .breadcrumb a:focus-visible {
  color: var(--brand-orange-600);
  border-bottom-color: var(--brand-orange-500);
}

.page-about .about-hero__eyebrow {
  display: inline-block;
  margin: 0 0 14px;
  padding: 5px 12px;
  background: var(--white);
  border: var(--border-w) solid var(--brand-orange-600);
  border-radius: var(--radius-pill);
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--brand-orange-600);
}

.page-about .about-hero__title {
  margin: 0 0 16px;
  max-width: 22ch;
  font-size: clamp(2rem, 7.4vw, 3.5rem);
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: -0.025em;
  color: var(--ink-900);
}

.page-about .about-hero__lead {
  max-width: 62ch;
  margin: 0 0 22px;
  font-size: 1.02rem;
  line-height: 1.8;
  color: var(--ink-500);
}

.page-about .about-hero__facts {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-hero__facts li {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 7px 14px;
  background: var(--white);
  border: var(--border-w) solid var(--ink-900);
  border-radius: var(--radius-pill);
  font-size: 0.88rem;
  color: var(--ink-700);
}

.page-about .about-hero__facts .mono {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--brand-orange-600);
}

/* ---------- 主体骨架：左侧时间轴 + 右侧章节 ---------- */
.page-about .about-shell {
  display: grid;
  grid-template-columns: 1fr;
  gap: 22px;
  width: min(var(--shell-max), 100% - var(--gutter) * 2);
  margin: 0 auto;
  padding: 30px 0 64px;
}

.page-about .about-rail__eyebrow {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--grey-500);
}

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

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

.page-about .about-rail__link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  background: var(--white);
  border: var(--border-w) solid var(--ink-900);
  border-radius: var(--radius-pill);
  color: var(--ink-900);
  text-decoration: none;
  font-size: 0.84rem;
  white-space: nowrap;
  transition: background 0.18s var(--ease), color 0.18s var(--ease),
    box-shadow 0.18s var(--ease);
}

.page-about .about-rail__link .mono {
  font-weight: 700;
  color: var(--brand-orange-600);
}

.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  background: var(--ink-900);
  color: var(--white);
  box-shadow: var(--shadow-hard);
}

.page-about .about-rail__link:hover .mono,
.page-about .about-rail__link:focus-visible .mono {
  color: var(--brand-orange-500);
}

.page-about .about-flow {
  min-width: 0;
  display: flex;
  flex-direction: column;
}

/* ---------- 章节通用 ---------- */
.page-about .about-sec {
  padding: 32px 0;
  border-top: var(--border-w) solid var(--grey-200);
  scroll-margin-top: 120px;
}

.page-about .about-sec:first-child {
  border-top: 0;
  padding-top: 4px;
}

.page-about .about-sec--apricot {
  border-top: 0;
  margin: 6px 0;
  padding: 26px 18px 30px;
  background: var(--apricot-100);
  border: var(--border-w) solid var(--ink-900);
  border-radius: var(--radius-card);
}

.page-about .chapter-num {
  display: inline-block;
  margin: 0 0 14px;
  padding: 5px 10px;
  background: var(--brand-orange-500);
  border-radius: 5px;
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-900);
  font-weight: 700;
}

.page-about .section-title {
  margin: 0 0 12px;
  max-width: 24ch;
  font-size: clamp(1.65rem, 4.6vw, 2.5rem);
  font-weight: 300;
  line-height: 1.22;
  letter-spacing: -0.02em;
  color: var(--ink-900);
}

.page-about .section-summary {
  max-width: 64ch;
  margin: 0 0 24px;
  padding-left: 16px;
  border-left: 4px solid var(--brand-orange-500);
  font-size: 1rem;
  line-height: 1.8;
  color: var(--ink-500);
}

/* ---------- 卡片 ---------- */
.page-about .about-cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

.page-about .about-card {
  background: var(--white);
  border: var(--border-w) solid var(--ink-900);
  border-radius: var(--radius-card);
  padding: 18px 18px 20px;
  transition: transform 0.18s var(--ease), box-shadow 0.18s var(--ease);
}

.page-about .about-card:hover {
  transform: translate(-3px, -3px);
  box-shadow: var(--shadow-hard);
}

.page-about .about-card .card-title {
  margin: 0 0 8px;
  font-size: 1.05rem;
  font-weight: 700;
  line-height: 1.45;
  color: var(--ink-900);
}

.page-about .about-card .card-text {
  margin: 0;
  font-size: 0.96rem;
  line-height: 1.78;
  color: var(--ink-500);
}

/* ---------- 7 → 5 合并 ---------- */
.page-about .merge-panel {
  margin-top: 8px;
  padding: 20px 16px;
  background: var(--white);
  border: var(--border-w) solid var(--ink-900);
  border-radius: var(--radius-card);
}

.page-about .merge-panel__title {
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--grey-500);
}

.page-about .merge-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .merge-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 24px minmax(0, 1fr);
  align-items: center;
  gap: 8px;
  padding: 11px 13px;
  background: var(--paper-50);
  border: var(--border-w) solid var(--ink-900);
  border-radius: 10px;
  transition: background 0.18s var(--ease), transform 0.18s var(--ease),
    box-shadow 0.18s var(--ease);
}

.page-about .merge-row:hover {
  background: var(--apricot-100);
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-hard);
}

.page-about .merge-old {
  font-size: 0.92rem;
  color: var(--grey-500);
  text-decoration: line-through;
  text-decoration-color: var(--brand-orange-500);
  text-decoration-thickness: 2px;
}

.page-about .merge-arrow {
  text-align: center;
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--brand-orange-500);
}

.page-about .merge-new {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--ink-900);
}

/* ---------- 栏目入口卡 ---------- */
.page-about .about-links {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

.page-about .about-link {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  grid-template-areas:
    "num title"
    "num text";
  gap: 4px 12px;
  align-items: start;
  padding: 16px;
  background: var(--white);
  border: var(--border-w) solid var(--ink-900);
  border-radius: var(--radius-card);
  text-decoration: none;
  color: inherit;
  transition: transform 0.18s var(--ease), box-shadow 0.18s var(--ease),
    background 0.18s var(--ease);
}

.page-about .about-link:hover,
.page-about .about-link:focus-visible {
  transform: translate(-3px, -3px);
  box-shadow: var(--shadow-hard);
  background: var(--apricot-100);
}

.page-about .about-link__num {
  grid-area: num;
  display: grid;
  place-items: center;
  width: 40px;
  height: 40px;
  border-radius: 9px;
  background: var(--brand-orange-500);
  color: var(--ink-900);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 700;
}

.page-about .about-link__title {
  grid-area: title;
  font-size: 1.02rem;
  font-weight: 700;
  color: var(--ink-900);
}

.page-about .about-link__text {
  grid-area: text;
  font-size: 0.92rem;
  line-height: 1.7;
  color: var(--ink-500);
}

/* ---------- 时间轴手风琴 ---------- */
.page-about .about-timeline {
  margin-top: 10px;
  border-top: var(--border-w) solid var(--ink-900);
}

.page-about .about-timeline .acc-item {
  border-bottom: 1px solid var(--grey-200);
}

.page-about .about-timeline .acc-trigger {
  width: 100%;
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 16px 2px;
  background: none;
  border: 0;
  text-align: left;
  cursor: pointer;
  font-family: var(--font-sans);
  font-size: 1.02rem;
  font-weight: 700;
  line-height: 1.5;
  color: var(--ink-900);
  transition: color 0.18s var(--ease);
}

.page-about .about-timeline .acc-trigger:hover,
.page-about .about-timeline .acc-trigger:focus-visible {
  color: var(--brand-orange-600);
}

.page-about .about-timeline .acc-trigger .mono {
  flex: 0 0 auto;
  padding: 3px 7px;
  background: var(--apricot-100);
  border: 1px solid var(--brand-orange-500);
  border-radius: 5px;
  font-size: 0.76rem;
  letter-spacing: 0.1em;
  color: var(--brand-orange-600);
}

.page-about .about-timeline .acc-panel-inner {
  max-width: 64ch;
  padding: 0 2px 20px;
  font-size: 0.96rem;
  line-height: 1.8;
  color: var(--ink-500);
}

/* ---------- 媒体 ---------- */
.page-about .about-media {
  margin: 0 0 24px;
  background: var(--white);
  border: var(--border-w) solid var(--ink-900);
  border-radius: var(--radius-card);
  overflow: hidden;
}

.page-about .about-media img {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .about-media .media-caption {
  display: block;
  padding: 10px 14px;
  background: var(--paper-50);
  border-top: 1px solid var(--grey-200);
  font-size: 0.83rem;
  line-height: 1.6;
  color: var(--grey-500);
}

/* ---------- 补充说明 ---------- */
.page-about .about-note {
  margin: 20px 0 0;
  padding: 14px 16px;
  background: var(--white);
  border-left: 5px solid var(--teal-500);
  border-radius: 0 10px 10px 0;
  font-size: 0.94rem;
  line-height: 1.78;
  color: var(--ink-500);
}

/* ---------- 尾部行动区 ---------- */
.page-about .about-cta {
  margin-top: 34px;
  padding: 30px 20px 32px;
  background: var(--ink-900);
  border-radius: var(--radius-card);
  color: var(--footer-text);
}

.page-about .about-cta__eyebrow {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: var(--fs-mono);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--brand-orange-500);
}

.page-about .about-cta__title {
  margin: 0 0 12px;
  font-size: clamp(1.5rem, 4vw, 2.1rem);
  font-weight: 300;
  line-height: 1.25;
  letter-spacing: -0.02em;
  color: var(--white);
}

.page-about .about-cta__text {
  max-width: 58ch;
  margin: 0 0 22px;
  font-size: 1rem;
  line-height: 1.8;
  color: var(--footer-text);
}

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

/* ---------- 平板 ---------- */
@media (min-width: 700px) {
  .page-about .about-cards,
  .page-about .about-links {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .page-about .about-sec {
    padding: 40px 0;
  }

  .page-about .about-sec--apricot {
    padding: 30px 26px 34px;
  }
}

/* ---------- 桌面：左侧固定时间轴 ---------- */
@media (min-width: 1000px) {
  .page-about .about-hero {
    padding: 52px 0 56px;
  }

  .page-about .about-hero::after {
    right: -90px;
    top: -70px;
    width: 300px;
    height: 300px;
  }

  .page-about .about-shell {
    grid-template-columns: 208px minmax(0, 1fr);
    gap: 56px;
    padding: 48px 0 96px;
  }

  .page-about .about-rail {
    position: sticky;
    top: 112px;
    align-self: start;
  }

  .page-about .about-rail__list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
    padding: 0;
    border-left: 1px solid var(--grey-200);
  }

  .page-about .about-rail__link {
    position: relative;
    padding: 9px 0 9px 18px;
    background: transparent;
    border: 0;
    border-radius: 0;
    white-space: normal;
    font-size: 0.9rem;
    color: var(--ink-500);
  }

  .page-about .about-rail__link::before {
    content: "";
    position: absolute;
    left: -5px;
    top: 50%;
    width: 9px;
    height: 9px;
    margin-top: -5px;
    border-radius: 50%;
    background: var(--paper-50);
    border: 2px solid var(--ink-900);
    transition: background 0.18s var(--ease), border-color 0.18s var(--ease),
      transform 0.18s var(--ease);
  }

  .page-about .about-rail__link:hover,
  .page-about .about-rail__link:focus-visible {
    background: transparent;
    color: var(--brand-orange-600);
    box-shadow: none;
  }

  .page-about .about-rail__link:hover::before,
  .page-about .about-rail__link:focus-visible::before {
    background: var(--brand-orange-500);
    border-color: var(--brand-orange-500);
    transform: scale(1.3);
  }
}

/* ---------- 大屏：三列卡片 ---------- */
@media (min-width: 1180px) {
  .page-about .about-cards--3 {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 减少动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .about-card,
  .page-about .about-link,
  .page-about .merge-row,
  .page-about .about-rail__link,
  .page-about .about-rail__link::before {
    transition: none;
  }

  .page-about .about-card:hover,
  .page-about .about-link:hover,
  .page-about .merge-row:hover {
    transform: none;
  }
}
<<<END>>>