.page-about {
  background: var(--ink-900);
  color: var(--paper);
  overflow-x: clip;
}

.page-about .about-crumbs {
  padding-top: clamp(18px, 3vw, 30px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 4vw, 44px);
  padding-block: clamp(24px, 4vw, 48px) clamp(44px, 6vw, 76px);
}

.page-about .about-hero-main .eyebrow {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--cyan);
  margin: 0 0 14px;
}

.page-about .about-hero-main h1 {
  margin: 0 0 18px;
  font-size: clamp(28px, 5.4vw, 46px);
  line-height: 1.16;
  letter-spacing: -0.02em;
  font-weight: 900;
}

.page-about .about-hero-main .lede {
  margin: 0;
  max-width: 60ch;
  color: var(--gray);
  line-height: 1.8;
}

.page-about .hero-facts {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 2px;
  background: var(--ink-700);
  border: 2px solid var(--ink-700);
}

.page-about .hero-fact {
  background: var(--ink-800);
  padding: 14px 14px 16px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.page-about .hero-fact-num {
  font-family: var(--font-mono);
  font-size: 22px;
  line-height: 1;
  color: var(--cyan);
  letter-spacing: -0.02em;
}

.page-about .hero-fact-label {
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--gray);
}

@media (min-width: 900px) {
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 1.5fr) minmax(0, 0.9fr);
    align-items: end;
    column-gap: clamp(32px, 5vw, 72px);
  }
}

/* ---------- 章节头 ---------- */
.page-about .about-chapter {
  padding-block: clamp(40px, 6vw, 78px);
  border-top: 1px solid var(--ink-700);
}

.page-about .chapter-head {
  margin-bottom: 26px;
}

.page-about .chapter-meta {
  margin: 0 0 12px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 12px;
}

.page-about .chapter-no {
  font-family: var(--font-mono);
  font-size: clamp(24px, 3.4vw, 34px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--cyan);
}

.page-about .chapter-no::after {
  content: "";
  display: inline-block;
  width: clamp(28px, 6vw, 72px);
  height: 2px;
  background: var(--ink-700);
  margin-left: 12px;
  vertical-align: middle;
}

.page-about .chapter-label {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--gray);
}

.page-about .chapter-title {
  margin: 0 0 12px;
  font-size: clamp(22px, 3.2vw, 30px);
  line-height: 1.24;
  letter-spacing: -0.02em;
  font-weight: 900;
}

.page-about .chapter-lede {
  margin: 0;
  max-width: 62ch;
  color: var(--gray);
  line-height: 1.8;
}

/* ---------- 时间轴 ---------- */
.page-about .timeline {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
}

.page-about .timeline-item {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  row-gap: 6px;
  padding: 20px 0 20px 24px;
  border-top: 1px solid var(--ink-700);
}

.page-about .timeline-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 26px;
  width: 9px;
  height: 9px;
  background: var(--ink-900);
  border: 2px solid var(--cyan);
}

.page-about .timeline-item:last-child::before {
  background: var(--orange);
  border-color: var(--orange);
}

.page-about .timeline-year {
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--cyan);
  letter-spacing: 0.02em;
}

.page-about .timeline-item:last-child .timeline-year {
  color: var(--orange);
}

.page-about .timeline-text {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--paper-2);
}

@media (min-width: 720px) {
  .page-about .timeline-item {
    grid-template-columns: 116px minmax(0, 1fr);
    column-gap: 22px;
    align-items: baseline;
    padding-left: 26px;
  }
}

/* ---------- 图片容器 ---------- */
.page-about .origin-figure {
  margin: 34px 0 0;
  aspect-ratio: 16 / 9;
}

.page-about .record-figure {
  margin: 32px 0 0;
  aspect-ratio: 3 / 2;
}

.page-about .team-figure {
  margin: 0;
  aspect-ratio: 3 / 4;
}

.page-about .origin-figure img,
.page-about .record-figure img,
.page-about .team-figure img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

@media (min-width: 760px) {
  .page-about .origin-figure {
    aspect-ratio: 1 / 1;
    max-width: 460px;
  }
}

/* ---------- 暖纸白区块 ---------- */
.page-about .paper-block {
  background: var(--paper);
  color: var(--ink-900);
  padding: clamp(24px, 4.5vw, 52px);
  border: 2px solid var(--ink-900);
  box-shadow: var(--shadow-solid);
}

.page-about .paper-block .chapter-no {
  color: var(--cyan-deep);
}

.page-about .paper-block .chapter-no::after {
  background: rgba(7, 27, 22, 0.18);
}

.page-about .paper-block .chapter-label {
  color: rgba(7, 27, 22, 0.55);
}

.page-about .paper-block .chapter-title {
  color: var(--ink-900);
}

.page-about .paper-block .chapter-lede {
  color: rgba(7, 27, 22, 0.75);
}

/* ---------- 字段结构 ---------- */
.page-about .field-diagram {
  margin: 28px 0 0;
  border: 2px solid var(--ink-900);
  background: var(--paper-2);
}

.page-about .field-layer {
  display: grid;
  grid-template-columns: 42px minmax(0, 1fr);
  column-gap: 16px;
  row-gap: 6px;
  padding: 16px;
  border-top: 1px solid rgba(7, 27, 22, 0.14);
  transition: background-color 0.25s var(--ease), box-shadow 0.25s var(--ease);
}

.page-about .field-layer:first-child {
  border-top: 0;
}

.page-about .field-layer:hover,
.page-about .field-layer:focus,
.page-about .field-layer:focus-visible {
  background: rgba(59, 224, 200, 0.2);
  box-shadow: inset 4px 0 0 var(--cyan-deep);
  outline: none;
}

.page-about .field-no {
  grid-row: span 2;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--cyan-deep);
  padding-top: 3px;
}

.page-about .field-name {
  font-size: 16px;
  font-weight: 700;
  line-height: 1.4;
}

.page-about .field-role {
  font-size: 14px;
  line-height: 1.72;
  color: rgba(7, 27, 22, 0.72);
}

.page-about .record-columns {
  margin-top: 28px;
  display: grid;
  gap: 20px;
}

.page-about .record-columns h3 {
  margin: 0 0 8px;
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.02em;
}

.page-about .record-columns p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(7, 27, 22, 0.76);
}

@media (min-width: 720px) {
  .page-about .record-columns {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.2fr);
    column-gap: clamp(24px, 4vw, 44px);
  }
}

/* ---------- 团队 ---------- */
.page-about .team-layout {
  display: grid;
  gap: clamp(24px, 4vw, 44px);
}

.page-about .team-cards {
  border-top: 1px solid var(--ink-700);
}

.page-about .team-card {
  padding: 20px 16px 20px 18px;
  border-bottom: 1px solid var(--ink-700);
  transition: background-color 0.25s var(--ease), box-shadow 0.25s var(--ease);
}

.page-about .team-card:hover,
.page-about .team-card:focus,
.page-about .team-card:focus-within {
  background: var(--ink-800);
  box-shadow: inset 4px 0 0 var(--cyan);
  outline: none;
}

.page-about .team-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 10px;
}

.page-about .team-role {
  margin: 0;
  font-size: 17px;
  font-weight: 800;
  letter-spacing: -0.01em;
}

.page-about .team-count {
  font-family: var(--font-mono);
  font-size: 19px;
  line-height: 1;
  color: var(--orange);
  white-space: nowrap;
}

.page-about .team-desc {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--gray);
}

@media (min-width: 880px) {
  .page-about .team-layout {
    grid-template-columns: minmax(0, 0.75fr) minmax(0, 1fr);
    align-items: start;
  }
}

/* ---------- 分类与复核 ---------- */
.page-about .topic-grid {
  margin-top: 28px;
  display: grid;
  gap: 2px;
  background: rgba(7, 27, 22, 0.16);
  border: 2px solid var(--ink-900);
}

.page-about .topic-item {
  background: var(--paper);
  padding: 18px 18px 20px;
}

.page-about .topic-item h3 {
  margin: 0 0 8px;
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-size: 16px;
  font-weight: 700;
}

.page-about .topic-item h3 .mono {
  font-size: 12px;
  color: var(--cyan-deep);
}

.page-about .topic-item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: rgba(7, 27, 22, 0.72);
}

.page-about .check-list {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
  border-top: 2px solid var(--ink-900);
}

.page-about .check-list li {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  row-gap: 4px;
  padding: 14px 0;
  border-bottom: 1px solid rgba(7, 27, 22, 0.16);
}

.page-about .check-key {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--cyan-deep);
}

.page-about .check-val {
  font-size: 14.5px;
  line-height: 1.75;
  color: rgba(7, 27, 22, 0.78);
}

@media (min-width: 640px) {
  .page-about .topic-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .check-list li {
    grid-template-columns: 148px minmax(0, 1fr);
    column-gap: 20px;
    align-items: baseline;
  }
}

/* ---------- 合作生态 ---------- */
.page-about .partner-grid {
  margin-top: 28px;
  display: grid;
  gap: 2px;
  background: var(--ink-700);
  border: 2px solid var(--ink-700);
}

.page-about .partner-stat {
  background: var(--ink-800);
  padding: 20px 18px 22px;
}

.page-about .partner-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 26px;
  line-height: 1;
  color: var(--cyan);
  margin-bottom: 12px;
  letter-spacing: -0.02em;
}

.page-about .partner-label {
  display: block;
  font-size: 13.5px;
  line-height: 1.65;
  color: var(--gray);
}

.page-about .partner-notes {
  margin-top: 26px;
  display: grid;
  gap: 16px;
}

.page-about .partner-notes p {
  margin: 0;
  max-width: 76ch;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--paper-2);
}

.page-about .partner-stat:nth-child(2) .partner-num {
  color: var(--orange);
}

@media (min-width: 640px) {
  .page-about .partner-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1000px) {
  .page-about .partner-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ---------- 收束跳转 ---------- */
.page-about .next-grid {
  margin-top: 28px;
  display: grid;
  gap: 18px;
}

.page-about .next-card {
  display: block;
  text-decoration: none;
  color: var(--paper);
  background: var(--ink-800);
  border: 2px solid var(--ink-700);
  padding: 22px 22px 24px;
  box-shadow: 8px 8px 0 rgba(0, 0, 0, 0.45);
  transition: transform 0.25s var(--ease), box-shadow 0.25s var(--ease), border-color 0.25s var(--ease);
}

.page-about .next-card:hover,
.page-about .next-card:focus,
.page-about .next-card:focus-visible {
  transform: translate(-2px, -2px);
  box-shadow: 12px 12px 0 rgba(0, 0, 0, 0.5);
  border-color: var(--cyan);
  outline: none;
}

.page-about .next-kicker {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--cyan);
  margin-bottom: 10px;
}

.page-about .next-title {
  display: block;
  font-size: 19px;
  font-weight: 800;
  letter-spacing: -0.01em;
  margin-bottom: 10px;
}

.page-about .next-desc {
  display: block;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--gray);
}

.page-about .chapter-foot-link {
  margin: 24px 0 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--gray);
}

.page-about .chapter-foot-link a {
  color: var(--cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .chapter-foot-link a:hover {
  color: var(--orange);
}

@media (min-width: 760px) {
  .page-about .next-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .field-layer,
  .page-about .team-card,
  .page-about .next-card {
    transition: none;
  }

  .page-about .next-card:hover,
  .page-about .next-card:focus-visible {
    transform: none;
  }
}