.page-about {
  --about-rail: 236px;
  --about-ink-soft: #2B3A4D;
  background-color: var(--sand);
  background-image: repeating-linear-gradient(
    112deg,
    rgba(14, 27, 43, 0.028) 0 1px,
    transparent 1px 9px
  );
  color: var(--night);
  font-family: var(--font-body);
  line-height: 1.8;
  padding-bottom: clamp(48px, 7vw, 96px);
  overflow-x: hidden;
}

.page-about .crumbs {
  padding-top: clamp(14px, 2.4vw, 22px);
  font-size: 13px;
  color: var(--dust);
}

.page-about .crumbs a {
  color: var(--jade);
  text-decoration: none;
}

.page-about .crumbs a:hover {
  text-decoration: underline;
}

.page-about .crumbs-sep {
  margin: 0 8px;
  color: var(--sand-deep);
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  padding: clamp(18px, 3.6vw, 40px) 0 clamp(28px, 5vw, 56px);
}

.page-about .about-hero-inner {
  display: grid;
  gap: clamp(24px, 4vw, 40px);
}

.page-about .about-hero h1 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(30px, 6vw, 60px);
  line-height: 1.06;
  letter-spacing: -0.02em;
  margin: 0.16em 0 0.5em;
  max-width: 15ch;
  color: var(--char);
}

.page-about .about-lede {
  margin: 0;
  font-size: clamp(15px, 1.7vw, 17px);
  line-height: 1.85;
  color: var(--about-ink-soft);
  max-width: 58ch;
}

.page-about .about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(18px, 3vw, 28px);
}

.page-about .about-stamp {
  padding: clamp(18px, 3vw, 26px);
  border: 1px solid var(--sand-deep);
  align-self: start;
}

.page-about .stamp-kicker {
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--dust);
  padding-left: 26px;
  position: relative;
}

.page-about .stamp-kicker::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 16px;
  height: 2px;
  background: var(--orange);
}

.page-about .stamp-list {
  margin: 0;
  display: grid;
  gap: 14px;
}

.page-about .stamp-row {
  display: grid;
  gap: 2px;
  padding-bottom: 13px;
  border-bottom: 1px solid var(--line-soft);
}

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

.page-about .stamp-row dt {
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--dust);
}

.page-about .stamp-row dd {
  margin: 0;
  font-size: 15px;
  font-weight: 500;
  color: var(--night);
  line-height: 1.5;
}

.page-about .stamp-row dd .meta-mono {
  font-size: 18px;
  font-weight: 600;
  color: var(--jade);
}

/* ---------- 双栏正文 ---------- */

.page-about .article-layout {
  display: grid;
  gap: clamp(28px, 4vw, 48px);
  padding-top: clamp(22px, 3.5vw, 36px);
  border-top: 1px solid var(--line);
}

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

.page-about .rail-title {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--dust);
}

.page-about .rail-list {
  list-style: none;
  margin: 14px 0 0;
  padding: 0;
  border-left: 1px solid var(--line);
}

.page-about .rail-link {
  display: grid;
  grid-template-columns: 26px 1fr;
  gap: 6px;
  align-items: baseline;
  margin-left: -1px;
  padding: 10px 0 10px 14px;
  border-left: 2px solid transparent;
  color: var(--dust);
  font-size: 13.5px;
  line-height: 1.45;
  text-decoration: none;
  transition: color 0.2s ease, border-color 0.2s ease;
}

.page-about .rail-link:hover {
  color: var(--night);
  border-left-color: var(--sand-deep);
}

.page-about .rail-link[aria-current="true"] {
  color: var(--night);
  border-left-color: var(--orange);
  font-weight: 700;
}

.page-about .rail-num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--dust);
}

.page-about .rail-link[aria-current="true"] .rail-num {
  color: var(--orange);
}

/* ---------- 章节 ---------- */

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

.page-about .chapter {
  padding-top: clamp(30px, 5vw, 54px);
  scroll-margin-top: 96px;
}

.page-about .chapter:first-child {
  padding-top: 0;
}

.page-about .chapter-head {
  margin-bottom: clamp(16px, 2.6vw, 24px);
}

.page-about .chapter-num {
  margin: 0;
  font-size: 12px;
  letter-spacing: 0.24em;
  color: var(--orange);
  font-weight: 600;
}

.page-about .chapter h2 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(24px, 3.8vw, 40px);
  line-height: 1.16;
  letter-spacing: -0.015em;
  margin: 10px 0 0;
  max-width: 24ch;
  color: var(--char);
}

.page-about .chapter h2::after {
  content: "";
  display: block;
  width: 46px;
  height: 3px;
  margin-top: 16px;
  background: var(--orange);
}

.page-about .chapter p {
  margin: 0 0 1.15em;
  max-width: 68ch;
  font-size: 15.5px;
  color: var(--about-ink-soft);
}

.page-about .chapter-figure {
  margin: clamp(18px, 3vw, 28px) 0;
  border: 1px solid var(--line);
  background: var(--sand-deep);
}

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

.page-about .margin-quote {
  margin: clamp(20px, 3.4vw, 30px) 0;
  padding: 18px 22px;
  border-left: 3px solid var(--jade);
  background: rgba(31, 111, 107, 0.07);
  font-family: var(--font-display);
  font-size: clamp(16px, 2.1vw, 20px);
  font-weight: 700;
  line-height: 1.62;
  color: var(--night);
}

/* ---------- 数据事实条 ---------- */

.page-about .factbar {
  margin: clamp(28px, 4.5vw, 44px) 0 0;
  padding: 4px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  display: grid;
  gap: 0;
}

.page-about .fact {
  padding: 16px 0;
  display: grid;
  gap: 3px;
  align-content: start;
}

.page-about .fact-num {
  margin: 0;
  line-height: 1.1;
  display: flex;
  align-items: baseline;
  gap: 3px;
}

.page-about .fact-num .meta-mono {
  font-size: clamp(23px, 3.4vw, 32px);
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--night);
}

.page-about .fact-num em {
  font-style: normal;
  font-size: 12.5px;
  color: var(--dust);
  letter-spacing: 0.04em;
}

.page-about .fact-label {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.5;
  color: var(--dust);
  max-width: 24ch;
}

/* ---------- 流程 ---------- */

.page-about .flow {
  list-style: none;
  margin: 0 0 clamp(18px, 3vw, 26px);
  padding: 0;
  display: grid;
  gap: 0;
}

.page-about .flow li {
  position: relative;
  padding: 0 0 20px 20px;
  border-left: 1px solid var(--sand-deep);
}

.page-about .flow li:last-child {
  padding-bottom: 4px;
  border-left-color: transparent;
}

.page-about .flow li::before {
  content: "";
  position: absolute;
  left: -4.5px;
  top: 7px;
  width: 8px;
  height: 8px;
  background: var(--sand);
  border: 2px solid var(--jade);
  border-radius: 50%;
}

.page-about .flow-time {
  margin: 0 0 2px;
  font-size: 12.5px;
  letter-spacing: 0.12em;
  color: var(--jade);
  font-weight: 600;
}

.page-about .flow-text {
  margin: 0;
  max-width: 64ch;
  font-size: 15px;
  color: var(--about-ink-soft);
}

/* ---------- 折叠明细 ---------- */

.page-about .fact-details {
  margin: 0 0 clamp(18px, 3vw, 26px);
  border: 1px solid var(--line);
  background: var(--glass);
  padding: 0 16px;
}

.page-about .fact-details summary {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 14px;
  padding: 14px 0;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 15px;
  color: var(--night);
}

.page-about .fact-details summary::-webkit-details-marker {
  display: none;
}

.page-about .fact-details summary::after {
  content: "＋";
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--orange);
  line-height: 1;
}

.page-about .fact-details[open] summary::after {
  content: "－";
}

.page-about .fact-details-body {
  padding: 2px 0 16px;
  border-top: 1px solid var(--line-soft);
}

.page-about .role-list {
  list-style: none;
  margin: 0;
  padding: 12px 0 0;
  display: grid;
  gap: 10px;
}

.page-about .role-list li {
  font-size: 14.5px;
  line-height: 1.65;
  color: var(--about-ink-soft);
  padding-left: 34px;
  position: relative;
}

.page-about .role-num {
  position: absolute;
  left: 0;
  top: 0.1em;
  font-size: 15px;
  font-weight: 600;
  color: var(--jade);
}

/* ---------- 覆盖与合作 ---------- */

.page-about .coverage-grid {
  display: grid;
  gap: clamp(20px, 3vw, 32px);
  margin-bottom: clamp(16px, 2.5vw, 24px);
}

.page-about .coverage-copy {
  min-width: 0;
}

.page-about .project-list {
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px 14px;
}

.page-about .project-list li {
  display: flex;
  align-items: baseline;
  gap: 8px;
  font-size: 14.5px;
  color: var(--night);
  padding: 7px 0;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .project-num {
  font-size: 11px;
  color: var(--orange);
  letter-spacing: 0.06em;
}

.page-about .coverage-figure {
  margin: 0;
  border: 1px solid var(--line);
  background: var(--sand-deep);
}

/* ---------- 时间线 ---------- */

.page-about .timeline {
  list-style: none;
  margin: 0 0 clamp(18px, 3vw, 26px);
  padding: 0;
}

.page-about .tl-item {
  position: relative;
  padding: 0 0 clamp(22px, 3.2vw, 30px) 24px;
  border-left: 1px solid var(--sand-deep);
}

.page-about .tl-item:last-child {
  padding-bottom: 4px;
  border-left-color: transparent;
}

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: -6px;
  top: 6px;
  width: 9px;
  height: 9px;
  background: var(--sand);
  border: 2px solid var(--orange);
  border-radius: 50%;
}

.page-about .tl-year {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--orange);
}

.page-about .tl-title {
  margin: 4px 0 4px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(16px, 2.1vw, 19px);
  line-height: 1.4;
  color: var(--char);
}

.page-about .tl-body {
  margin: 0;
  font-size: 14.8px;
  line-height: 1.7;
  color: var(--about-ink-soft);
  max-width: 58ch;
}

/* ---------- 结尾卡片 ---------- */

.page-about .outro {
  margin-top: clamp(26px, 4vw, 40px);
  padding: clamp(22px, 4vw, 40px);
  background: var(--night);
  border-left: 4px solid var(--orange);
  display: grid;
  gap: 14px;
}

.page-about .outro h2 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(20px, 2.8vw, 28px);
  line-height: 1.25;
  letter-spacing: -0.01em;
  margin: 0;
  color: var(--sand);
  max-width: 20ch;
}

.page-about .outro h2::after {
  display: none;
}

.page-about .outro-text {
  margin: 0;
  max-width: 58ch;
  font-size: 14.5px;
  line-height: 1.85;
  color: #D9C4A5;
}

.page-about .outro-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 4px;
}

/* ---------- 响应式 ---------- */

@media (min-width: 640px) {
  .page-about .factbar {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .fact {
    padding: 18px 0;
  }

  .page-about .fact + .fact {
    border-left: 1px solid var(--line);
    padding-left: clamp(16px, 2.6vw, 26px);
  }
}

@media (min-width: 860px) {
  .page-about .about-hero-inner {
    grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr);
    align-items: end;
  }

  .page-about .coverage-grid {
    grid-template-columns: minmax(0, 1.25fr) minmax(0, 0.75fr);
    align-items: start;
  }

  .page-about .project-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 1000px) {
  .page-about .article-layout {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    column-gap: clamp(36px, 5vw, 68px);
    align-items: start;
  }

  .page-about .rail {
    display: block;
    position: sticky;
    top: 92px;
  }

  .page-about .chapter p {
    font-size: 16px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .rail-link {
    transition: none;
  }
}
<<<END>>>