.page-about {
  --about-muted: #4A463D;
  --about-line: rgba(26, 26, 24, 0.12);
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-sans);
  overflow-x: hidden;
}

/* ===== 首屏 ===== */
.page-about .about-hero {
  position: relative;
  background: var(--green);
  color: var(--paper);
  padding: clamp(22px, 4vw, 36px) 0 clamp(44px, 7vw, 92px);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: repeating-linear-gradient(
    90deg,
    rgba(246, 241, 231, 0.055) 0 1px,
    transparent 1px 72px
  );
}

.page-about .about-hero > .shell {
  position: relative;
  z-index: 1;
}

.page-about .about-crumb .breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: 12px;
  letter-spacing: 0.04em;
}

.page-about .about-crumb a {
  color: var(--paper-70);
  text-decoration: none;
}

.page-about .about-crumb a:hover,
.page-about .about-crumb a:focus-visible {
  color: var(--gold);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .about-crumb .breadcrumb__sep {
  color: var(--gold);
}

.page-about .about-crumb [aria-current="page"] {
  color: var(--paper);
}

.page-about .hero-grid {
  display: grid;
  gap: clamp(26px, 4vw, 52px);
  margin-top: clamp(24px, 4vw, 46px);
}

.page-about .hero-stamp {
  margin: 0;
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--gold);
}

.page-about .about-hero h1 {
  margin: 16px 0 0;
  font-size: clamp(32px, 6vw, 72px);
  line-height: 1.04;
  letter-spacing: -0.02em;
  font-weight: 900;
  max-width: 15em;
}

.page-about .hero-lede {
  margin: 22px 0 0;
  max-width: 36em;
  font-size: 16px;
  line-height: 1.8;
  color: var(--paper-70);
}

.page-about .hero-figure {
  margin: 0;
  border: 1px solid var(--line-light);
  border-radius: var(--radius-m);
  overflow: hidden;
  background: var(--green-deep);
}

.page-about .hero-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .hero-figure figcaption {
  padding: 10px 14px;
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--paper-52);
  border-top: 1px solid var(--line-light);
}

.page-about .hero-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(32px, 5vw, 58px) 0 0;
  background: var(--line-light);
  border-top: 1px solid var(--line-light);
  border-bottom: 1px solid var(--line-light);
}

.page-about .stat {
  background: var(--green);
  padding: 16px 14px 18px 0;
}

.page-about .stat dt {
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--paper-52);
}

.page-about .stat dd {
  margin: 8px 0 0;
  font-weight: 700;
  font-size: clamp(21px, 3vw, 30px);
  line-height: 1.1;
  color: var(--gold);
}

/* ===== 正文骨架 ===== */
.page-about .about-body {
  padding-top: clamp(40px, 6vw, 84px);
  padding-bottom: clamp(48px, 7vw, 96px);
}

.page-about .block {
  padding-bottom: clamp(34px, 5vw, 62px);
  margin-bottom: clamp(34px, 5vw, 62px);
  border-bottom: 1px solid var(--about-line);
}

.page-about .block:last-of-type {
  border-bottom: 0;
  margin-bottom: clamp(24px, 4vw, 44px);
}

.page-about .block-head {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 12px 14px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--green);
}

.page-about .block-num {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.16em;
  color: var(--gold);
}

.page-about .block-title {
  margin: 0;
  font-size: clamp(23px, 3.4vw, 38px);
  line-height: 1.18;
  letter-spacing: -0.01em;
  font-weight: 900;
}

.page-about .block-lede {
  margin: 18px 0 0;
  max-width: 48ch;
  font-size: 15px;
  line-height: 1.85;
  color: var(--about-muted);
}

/* ===== 版本区：粘性索引 + 时间轴条目 ===== */
.page-about .versions-grid {
  display: grid;
  gap: clamp(24px, 4vw, 40px);
}

.page-about .rail {
  align-self: start;
}

.page-about .rail-title {
  margin: 0 0 12px;
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--grey);
}

.page-about .rail-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .rail-list a {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 6px 12px;
  font-size: 13px;
  color: var(--about-muted);
  text-decoration: none;
  border: 1px solid var(--about-line);
  border-radius: 999px;
  background: var(--paper);
  transition: border-color 220ms var(--ease), color 220ms var(--ease), background 220ms var(--ease);
}

.page-about .rail-list .mono {
  color: var(--gold);
  font-weight: 700;
  font-size: 11px;
}

.page-about .rail-list a:hover,
.page-about .rail-list a:focus-visible {
  color: var(--green);
  border-color: var(--gold);
  background: var(--moss);
}

.page-about .versions-main .block-head {
  margin-bottom: 18px;
}

.page-about .era {
  padding: 0 0 clamp(24px, 3.5vw, 38px);
  margin-bottom: clamp(24px, 3.5vw, 38px);
  border-bottom: 1px dashed var(--about-line);
}

.page-about .era:last-child {
  padding-bottom: 0;
  margin-bottom: 0;
  border-bottom: 0;
}

.page-about .era-head {
  display: flex;
  align-items: center;
  gap: 12px;
}

.page-about .era-num {
  display: inline-block;
  padding: 3px 9px;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--paper);
  background: var(--green);
  border-radius: var(--radius-s);
}

.page-about .era-tag {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--grey);
}

.page-about .era-title {
  margin: 14px 0 0;
  font-size: clamp(19px, 2.4vw, 26px);
  line-height: 1.35;
  font-weight: 900;
}

.page-about .era-text {
  margin: 12px 0 0;
  max-width: 58ch;
  font-size: 15px;
  line-height: 1.85;
  color: var(--about-muted);
}

.page-about .era-shift {
  margin-top: 16px;
  padding-left: 14px;
  border-left: 3px solid var(--gold);
  display: grid;
  gap: 5px;
}

.page-about .era-shift__label {
  font-size: 10px;
  letter-spacing: 0.16em;
  color: var(--gold);
}

.page-about .era-shift p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink);
}

/* 结构草图 */
.page-about .tree {
  margin-top: 20px;
  padding: 16px;
  background: var(--moss);
  border-radius: var(--radius-m);
  display: grid;
  gap: 8px;
}

.page-about .tree-row {
  display: flex;
  gap: 6px;
  align-items: center;
}

.page-about .tree-row--bar {
  padding-bottom: 6px;
  border-bottom: 1px solid rgba(11, 61, 46, 0.18);
}

.page-about .tree-box {
  flex: 1 1 auto;
  height: 15px;
  border-radius: 2px;
  background: rgba(11, 61, 46, 0.24);
}

.page-about .tree-box--thin {
  height: 9px;
  background: rgba(11, 61, 46, 0.18);
}

.page-about .tree-box--tick {
  flex: 1 1 0;
  height: 20px;
  background: rgba(11, 61, 46, 0.16);
}

.page-about .tree-box--gold {
  background: var(--gold);
}

.page-about .tree-box--amber {
  background: var(--amber);
}

.page-about .tree-box--teal {
  background: var(--teal);
}

.page-about .tree-box--coral {
  background: var(--coral);
}

.page-about .tree-box--tag {
  flex: 0 0 28px;
  height: 12px;
}

.page-about .tree-cap {
  margin: 4px 0 0;
  font-size: 12px;
  line-height: 1.6;
  color: #4F5C51;
}

/* ===== 编目线索 ===== */
.page-about .clues {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--about-line);
  border-top: 1px solid var(--about-line);
  border-bottom: 1px solid var(--about-line);
}

.page-about .clues li {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  gap: 4px 16px;
  padding: 20px 0;
  background: var(--paper);
}

.page-about .clue-idx {
  grid-row: span 2;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--gold);
  padding-top: 3px;
}

.page-about .clues h3 {
  margin: 0;
  font-size: 17px;
  line-height: 1.4;
  font-weight: 900;
}

.page-about .clues p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--about-muted);
}

.page-about .worktable {
  margin: 26px 0 0;
}

.page-about .worktable img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  border-radius: var(--radius-m);
  object-fit: cover;
  border: 1px solid var(--about-line);
}

.page-about .worktable figcaption {
  margin-top: 10px;
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--grey);
}

/* ===== 审校三步 ===== */
.page-about .checks {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .check {
  padding: 20px 18px 22px;
  background: var(--paper);
  border: 1px solid var(--about-line);
  border-top: 4px solid var(--green);
  border-radius: var(--radius-s);
}

.page-about .check-num {
  display: block;
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--gold);
  font-weight: 700;
}

.page-about .check h3 {
  margin: 10px 0 0;
  font-size: 20px;
  font-weight: 900;
  line-height: 1.3;
}

.page-about .check p {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--about-muted);
}

/* ===== 团队 ===== */
.page-about .team {
  margin-top: 24px;
  display: grid;
  gap: 14px;
}

.page-about .team-card {
  padding: 22px 20px 24px;
  background: var(--green);
  color: var(--paper);
  border-radius: var(--radius-m);
}

.page-about .team-card:nth-child(2) {
  background: var(--green-deep);
}

.page-about .team-card:nth-child(3) {
  background: var(--teal);
}

.page-about .team-num {
  margin: 0;
  font-size: clamp(34px, 5vw, 46px);
  font-weight: 700;
  line-height: 1;
  color: var(--gold);
}

.page-about .team-card h3 {
  margin: 14px 0 0;
  font-size: 17px;
  font-weight: 900;
  letter-spacing: 0.02em;
}

.page-about .team-card p {
  margin: 8px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--paper-70);
}

/* ===== 服务范围 ===== */
.page-about .reach {
  margin-top: 24px;
  display: grid;
  gap: 26px;
}

.page-about .reach-figure {
  margin: 0;
}

.page-about .reach-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border-radius: var(--radius-m);
  border: 1px solid var(--about-line);
}

.page-about .reach-figure figcaption {
  margin-top: 10px;
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--grey);
}

.page-about .reach-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 18px;
}

.page-about .reach-list li {
  display: grid;
  grid-template-columns: 76px minmax(0, 1fr);
  gap: 16px;
  align-items: start;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--about-line);
}

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

.page-about .reach-num {
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--green);
  padding-top: 2px;
  word-break: break-word;
}

.page-about .reach-list h3 {
  margin: 0;
  font-size: 16px;
  font-weight: 900;
  line-height: 1.4;
}

.page-about .reach-list p {
  margin: 6px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--about-muted);
}

/* ===== 下一步 ===== */
.page-about .about-next {
  padding: clamp(26px, 4vw, 44px);
  background: var(--moss);
  border-radius: var(--radius-l);
  border: 1px solid var(--about-line);
}

.page-about .about-next h2 {
  margin: 0;
  font-size: clamp(21px, 3vw, 30px);
  line-height: 1.25;
  font-weight: 900;
}

.page-about .about-next > p {
  margin: 14px 0 0;
  max-width: 46ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--about-muted);
}

.page-about .next-links {
  margin-top: 22px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .next-mail {
  margin: 20px 0 0;
  font-size: 13px;
  color: var(--about-muted);
}

.page-about .next-mail a {
  color: var(--green);
  text-decoration: underline;
  text-underline-offset: 3px;
  word-break: break-all;
}

/* ===== 断点 ===== */
@media (min-width: 700px) {
  .page-about .hero-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .stat {
    padding: 20px 16px 22px 0;
  }

  .page-about .checks {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 14px;
  }

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

  .page-about .clues li {
    grid-template-columns: 52px 190px minmax(0, 1fr);
    align-items: start;
    gap: 6px 24px;
    padding: 22px 0;
  }

  .page-about .clue-idx {
    grid-row: span 2;
  }
}

@media (min-width: 900px) {
  .page-about .hero-grid {
    grid-template-columns: minmax(0, 1.32fr) minmax(0, 0.86fr);
    align-items: end;
  }

  .page-about .reach {
    grid-template-columns: minmax(0, 0.78fr) minmax(0, 1fr);
    gap: clamp(26px, 4vw, 48px);
    align-items: start;
  }
}

@media (min-width: 960px) {
  .page-about .versions-grid {
    grid-template-columns: 178px minmax(0, 1fr);
    gap: clamp(32px, 4vw, 56px);
  }

  .page-about .rail {
    position: sticky;
    top: 96px;
  }

  .page-about .rail-list {
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 2px;
  }

  .page-about .rail-list a {
    display: flex;
    padding: 9px 0 9px 14px;
    border: 0;
    border-left: 2px solid var(--about-line);
    border-radius: 0;
    background: transparent;
    font-size: 14px;
    transition: border-color 220ms var(--ease), color 220ms var(--ease);
  }

  .page-about .rail-list a:hover,
  .page-about .rail-list a:focus-visible {
    background: transparent;
    border-left-color: var(--gold);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .rail-list a,
  .page-about .tree-box {
    transition: none;
  }
}
<<<END>>>