.page-about {
  background: var(--charcoal);
  color: var(--cold);
  font-family: var(--font-body);
  overflow-x: clip;
}

.page-about .num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.01em;
}

.page-about a:focus-visible {
  outline: 2px solid var(--mint);
  outline-offset: 2px;
}

.page-about .breadcrumb {
  padding-top: clamp(16px, 3vw, 24px);
  font-size: 12px;
}

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

.page-about .breadcrumb-item a {
  color: var(--steel);
  text-decoration: none;
}

.page-about .breadcrumb-item a:hover {
  color: var(--mint);
}

.page-about .breadcrumb-sep {
  color: var(--line);
}

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

/* ---------- 首屏 ---------- */
.page-about .hero {
  padding-block: clamp(20px, 4vw, 40px) clamp(32px, 5vw, 56px);
}

.page-about .hero-eyebrow {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0;
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--steel);
}

.page-about .hero-eyebrow .num {
  color: var(--ember);
}

.page-about .hero-title {
  margin: 18px 0 0;
  max-width: 17em;
  font-family: var(--font-display);
  font-size: clamp(30px, 6.2vw, 66px);
  font-weight: 300;
  line-height: 1.07;
  letter-spacing: -0.02em;
  color: var(--cold);
}

.page-about .hero-lede {
  margin: 22px 0 0;
  max-width: 60ch;
  font-size: clamp(15px, 1.7vw, 17px);
  line-height: 1.8;
  color: rgba(246, 247, 249, 0.84);
}

.page-about .hero-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 34px 0 0;
  padding: 0;
  background: var(--line);
  border: 1px solid var(--line);
}

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

.page-about .stat dt {
  margin: 0;
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--steel);
}

.page-about .stat dd {
  margin: 6px 0 0;
  font-size: clamp(22px, 3.2vw, 32px);
  font-weight: 600;
  line-height: 1.1;
  color: var(--ember);
}

/* ---------- 章节索引 ---------- */
.page-about .chapter-nav {
  border-block: 1px solid var(--line);
  background: var(--ink);
}

.page-about .chapter-nav-inner {
  display: flex;
  align-items: center;
  gap: 12px;
  padding-block: 10px;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .chapter-nav-label {
  flex: 0 0 auto;
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--mint);
}

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

.page-about .chapter-list a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  min-height: 44px;
  padding: 0 12px;
  border: 1px solid var(--line);
  color: var(--cold);
  font-size: 13px;
  text-decoration: none;
  white-space: nowrap;
  transition: border-color 200ms ease-out, color 200ms ease-out;
}

.page-about .chapter-list a .num {
  font-size: 11px;
  color: var(--ember);
}

.page-about .chapter-list a:hover {
  border-color: var(--mint);
  color: var(--mint);
}

/* ---------- 展览墙式章节 ---------- */
.page-about .exh {
  position: relative;
  border-top: 1px solid var(--line);
  padding-block: clamp(40px, 7vw, 88px);
}

.page-about .exh-inner {
  display: grid;
  gap: clamp(22px, 3.4vw, 44px);
}

.page-about .exh-index {
  display: block;
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--ember);
}

.page-about .exh-title {
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-size: clamp(25px, 4.4vw, 42px);
  font-weight: 300;
  line-height: 1.16;
  letter-spacing: -0.015em;
  color: var(--cold);
}

.page-about .exh-kicker {
  margin: 12px 0 0;
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--steel);
}

.page-about .exh-body > p {
  margin: 16px 0 0;
  max-width: 66ch;
  font-size: 16px;
  line-height: 1.8;
  color: rgba(246, 247, 249, 0.8);
}

.page-about .exh-body > p.exh-lead {
  margin-top: 0;
  font-size: clamp(16px, 1.8vw, 18px);
  color: var(--cold);
}

.page-about .exh-body a {
  color: var(--mint);
  text-decoration: none;
  border-bottom: 1px solid rgba(59, 240, 196, 0.45);
}

.page-about .exh-body a:hover {
  border-bottom-color: var(--mint);
}

/* ---------- 项目标签 ---------- */
.page-about .project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .project-tags li {
  padding: 6px 10px;
  border: 1px solid var(--line);
  background: rgba(246, 247, 249, 0.04);
  font-size: 13px;
  color: var(--cold);
}

/* ---------- 档案卡 ---------- */
.page-about .arch {
  margin-top: 26px;
  border: 1px solid var(--line);
  background: rgba(246, 247, 249, 0.035);
  padding: 18px 18px 0;
}

.page-about .arch-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.page-about .arch-num {
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--ember);
}

.page-about .arch-tag {
  padding: 4px 8px;
  background: var(--amber);
  color: var(--charcoal);
  font-size: 11px;
  letter-spacing: 0.14em;
}

.page-about .arch-title {
  margin: 12px 0 0;
  font-size: clamp(18px, 2.2vw, 21px);
  font-weight: 600;
  line-height: 1.4;
  color: var(--cold);
}

.page-about .exh-body .arch-text {
  margin: 8px 0 16px;
  font-size: 15px;
  line-height: 1.75;
  color: rgba(246, 247, 249, 0.78);
}

.page-about .arch-foot {
  margin: 0 -18px;
  padding: 12px 18px;
  border-top: 1px solid var(--line);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--steel);
}

/* ---------- 四道工序 ---------- */
.page-about .steps {
  display: grid;
  gap: 1px;
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .step {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 12px;
  background: var(--charcoal);
  padding: 16px 18px;
}

.page-about .step-num {
  padding-top: 3px;
  font-size: 12px;
  color: var(--ember);
}

.page-about .step-title {
  margin: 0;
  font-size: 17px;
  font-weight: 600;
  color: var(--cold);
}

.page-about .step-main p {
  margin: 6px 0 0;
  font-size: 15px;
  line-height: 1.75;
  color: rgba(246, 247, 249, 0.76);
}

/* ---------- 图片 ---------- */
.page-about .shot {
  margin: 28px 0 0;
}

.page-about .shot img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  clip-path: polygon(0 2.4%, 100% 0, 100% 97.6%, 0 100%);
}

.page-about .shot-cap {
  margin-top: 10px;
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--steel);
}

/* ---------- 团队 ---------- */
.page-about .roles {
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.page-about .role {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  gap: 12px;
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .role-index {
  font-size: 13px;
  color: var(--mint);
}

.page-about .role-title {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px;
  margin: 0;
  font-size: 16px;
  font-weight: 600;
  color: var(--cold);
}

.page-about .role-count {
  padding: 2px 6px;
  background: var(--mint);
  color: var(--charcoal);
  font-size: 12px;
  font-weight: 600;
}

.page-about .role-text {
  margin: 6px 0 0;
  font-size: 15px;
  line-height: 1.75;
  color: rgba(246, 247, 249, 0.76);
}

/* ---------- 暖纸色章节 ---------- */
.page-about .exh--paper {
  background: var(--paper);
  color: var(--charcoal);
  border-top-color: rgba(20, 22, 26, 0.2);
}

.page-about .exh--paper .exh-index {
  color: var(--ember-deep);
}

.page-about .exh--paper .exh-title {
  color: var(--charcoal);
}

.page-about .exh--paper .exh-kicker,
.page-about .exh--paper .shot-cap {
  color: #6f665a;
}

.page-about .exh--paper .exh-body > p {
  color: #3a3f46;
}

.page-about .exh--paper .exh-body > p.exh-lead {
  color: var(--charcoal);
}

.page-about .exh--paper .exh-body a {
  color: var(--ember-deep);
  border-bottom-color: rgba(201, 58, 11, 0.4);
}

.page-about .shot--archive {
  margin-top: 20px;
}

/* ---------- 版本时间尺 ---------- */
.page-about .rail {
  display: grid;
  gap: 10px;
  margin-top: 24px;
}

.page-about .rail-node {
  border: 1px solid rgba(20, 22, 26, 0.22);
  background: rgba(255, 255, 255, 0.5);
}

.page-about .rail-sum {
  display: flex;
  align-items: center;
  gap: 10px;
  min-height: 52px;
  padding: 10px 14px;
  cursor: pointer;
  list-style: none;
}

.page-about .rail-sum::-webkit-details-marker {
  display: none;
}

.page-about .rail-dot {
  flex: 0 0 auto;
  width: 12px;
  height: 12px;
  background: var(--ember-deep);
}

.page-about .rail-ver {
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--charcoal);
}

.page-about .rail-name {
  font-size: 15px;
  font-weight: 600;
  color: var(--charcoal);
}

.page-about .rail-nowflag {
  margin-left: auto;
  padding: 3px 8px;
  background: var(--charcoal);
  color: var(--mint);
  font-size: 11px;
  letter-spacing: 0.14em;
}

.page-about .rail-node[open] {
  border-color: var(--ember-deep);
}

.page-about .rail-node[open] .rail-sum {
  border-bottom: 1px solid rgba(20, 22, 26, 0.16);
}

.page-about .rail-text {
  margin: 0;
  padding: 12px 14px 16px;
  font-size: 14px;
  line-height: 1.75;
  color: #33383f;
}

.page-about .rail-node--now {
  box-shadow: 0 0 0 2px var(--mint);
}

.page-about .rail-node--now .rail-dot {
  background: var(--mint);
  box-shadow: inset 0 0 0 2px var(--charcoal);
}

/* ---------- 覆盖与规模 ---------- */
.page-about .exh--reach {
  overflow: hidden;
  border-top: 1px solid var(--line);
  padding-block: clamp(44px, 7vw, 92px);
}

.page-about .reach-figure {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.page-about .reach-figure img {
  display: block;
  width: 100%;
  height: 100%;
  max-width: 100%;
  object-fit: cover;
  opacity: 0.34;
}

.page-about .exh--reach::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  background: linear-gradient(180deg, var(--charcoal) 0%, rgba(20, 22, 26, 0.72) 45%, var(--charcoal) 100%);
}

.page-about .exh--reach .exh-inner {
  position: relative;
  z-index: 2;
}

.page-about .reach-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .reach-item {
  background: rgba(8, 9, 11, 0.84);
  padding: 14px 16px;
}

.page-about .reach-item b {
  display: block;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(21px, 3.2vw, 30px);
  font-weight: 600;
  line-height: 1.1;
  color: var(--mint);
}

.page-about .reach-item span {
  display: block;
  margin-top: 6px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--steel);
}

/* ---------- 合作 ---------- */
.page-about .partner-grid {
  display: grid;
  gap: 12px;
  margin-top: 24px;
}

.page-about .partner-card {
  display: grid;
  gap: 6px;
  padding: 16px 18px;
  border: 1px solid var(--line);
  background: rgba(246, 247, 249, 0.035);
}

.page-about .partner-num {
  font-size: clamp(26px, 4vw, 38px);
  font-weight: 600;
  line-height: 1;
  color: var(--ember);
}

.page-about .partner-title {
  margin: 0;
  font-size: 16px;
  font-weight: 600;
  color: var(--cold);
}

.page-about .partner-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: rgba(246, 247, 249, 0.76);
}

/* ---------- 结尾行动区 ---------- */
.page-about .about-cta {
  border-top: 1px solid var(--line);
  background: var(--ink);
  padding-block: clamp(40px, 6vw, 72px);
}

.page-about .about-cta-title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(23px, 3.6vw, 34px);
  font-weight: 300;
  line-height: 1.2;
  letter-spacing: -0.01em;
  color: var(--cold);
}

.page-about .about-cta p {
  margin: 14px 0 0;
  max-width: 58ch;
  font-size: 16px;
  line-height: 1.75;
  color: rgba(246, 247, 249, 0.78);
}

.page-about .about-cta .btn-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

/* ---------- 断点 ---------- */
@media (min-width: 720px) {
  .page-about .hero-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .reach-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

  .page-about .partner-card:first-child {
    grid-column: span 2;
  }

  .page-about .step {
    grid-template-columns: 56px minmax(0, 1fr);
  }

  .page-about .role {
    grid-template-columns: 64px minmax(0, 1fr);
  }
}

@media (min-width: 900px) {
  .page-about .exh-inner {
    grid-template-columns: minmax(0, 4fr) minmax(0, 8fr);
    gap: clamp(28px, 4vw, 64px);
    align-items: start;
  }

  .page-about .exh-aside {
    position: sticky;
    top: 80px;
  }

  .page-about .exh--paper .exh-aside {
    position: static;
  }

  .page-about .rail {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 12px;
    padding-top: 18px;
    position: relative;
    align-items: start;
  }

  .page-about .rail::before {
    content: "";
    position: absolute;
    top: 6px;
    left: 0;
    right: 0;
    height: 1px;
    background: rgba(20, 22, 26, 0.3);
  }

  .page-about .rail-node {
    background: rgba(255, 255, 255, 0.56);
  }

  .page-about .rail-sum {
    flex-wrap: wrap;
    align-items: flex-start;
    min-height: 64px;
    padding: 12px 12px 10px;
  }

  .page-about .rail-nowflag {
    margin-left: 0;
  }
}

@media (min-width: 1100px) {
  .page-about .hero-stats {
    max-width: 960px;
  }

  .page-about .exh-body > p {
    font-size: 16px;
  }
}
<<<END>>>