.page-about {
  --about-rail: 96px;
  --about-pad: clamp(48px, 8vw, 104px);
  background: var(--sand-50);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  overflow-x: clip;
}

.page-about h1,
.page-about h2,
.page-about h3 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.08;
  letter-spacing: -0.01em;
}

.page-about p {
  margin: 0;
}

.page-about .breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--ink-soft);
}

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

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

.page-about .about-crumb-sep {
  color: var(--sand-300);
}

.page-about .eyebrow {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  margin: 0 0 16px;
}

.page-about .about-inline-link {
  color: var(--indigo-950);
  text-decoration: none;
  border-bottom: 1px solid var(--signal);
  padding-bottom: 1px;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.page-about .about-inline-link:hover,
.page-about .about-inline-link:focus-visible {
  color: var(--signal);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(20px, 4vw, 40px) 0 clamp(40px, 6vw, 84px);
  background:
    radial-gradient(110% 78% at 92% 0%, rgba(232, 111, 44, 0.13), transparent 58%),
    var(--sand-50);
}

.page-about .about-hero__layout {
  display: grid;
  gap: clamp(28px, 5vw, 56px);
  margin-top: clamp(22px, 4vw, 42px);
}

.page-about .about-hero h1 {
  font-size: clamp(34px, 7.4vw, 60px);
  max-width: 15em;
}

.page-about .about-hero__lead {
  margin-top: clamp(18px, 3vw, 26px);
  max-width: 34em;
  font-size: clamp(16px, 1.8vw, 18px);
  line-height: 1.78;
  color: var(--indigo-950);
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  margin: clamp(24px, 4vw, 36px) 0 0;
  padding: clamp(16px, 2.5vw, 22px) 0 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.page-about .about-stat {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.page-about .about-stat__num {
  font-family: var(--font-mono);
  font-size: clamp(24px, 4.4vw, 34px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--indigo-950);
}

.page-about .about-stat:nth-child(2) .about-stat__num {
  color: var(--signal);
}

.page-about .about-stat__label {
  font-size: 12px;
  line-height: 1.45;
  color: var(--ink-soft);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(24px, 4vw, 34px);
}

.page-about .about-hero__figure {
  margin: 0;
  position: relative;
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  aspect-ratio: 7 / 5;
  object-fit: cover;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 64px), calc(100% - 64px) 100%, 0 100%);
  filter: saturate(0.92) contrast(1.06);
}

.page-about .about-hero__caption {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--ink-soft);
}

.page-about .about-hero__caption::before {
  content: "";
  width: 26px;
  height: 1px;
  background: var(--signal);
  flex: 0 0 auto;
}

/* ---------- 通用区块骨架 ---------- */
.page-about .about-block {
  padding: var(--about-pad) 0;
  position: relative;
}

.page-about .about-block--flow {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-about .about-block--partners {
  background: var(--sand-100);
}

.page-about .about-split {
  display: grid;
  gap: clamp(18px, 3vw, 36px);
}

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

.page-about .about-index {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.14em;
  line-height: 1.7;
  color: var(--signal);
  padding: 1px 8px;
  border: 1px solid var(--sand-300);
}

.page-about .about-rail__label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--ink-soft);
  white-space: nowrap;
}

.page-about .about-h2 {
  font-size: clamp(26px, 4.8vw, 42px);
  max-width: 19em;
  margin-bottom: clamp(16px, 2.5vw, 26px);
}

.page-about .about-body > p {
  max-width: 38em;
  color: var(--indigo-950);
}

.page-about .about-body > p + p {
  margin-top: 16px;
}

.page-about .about-lede {
  font-size: clamp(16px, 1.8vw, 18px);
  line-height: 1.75;
  color: var(--ink-soft);
  max-width: 40em;
  margin-bottom: clamp(20px, 3vw, 30px);
}

.page-about .about-quote {
  margin: clamp(24px, 4vw, 36px) 0 0;
  padding: 18px 22px 18px 24px;
  border-left: 4px solid var(--signal);
  background: var(--sand-100);
  font-family: var(--font-display);
  font-size: clamp(18px, 2.4vw, 23px);
  font-weight: 700;
  line-height: 1.45;
  max-width: 30em;
}

/* ---------- 团队分工 ---------- */
.page-about .about-crew {
  list-style: none;
  margin: clamp(20px, 3vw, 32px) 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .about-crew__item {
  display: grid;
  grid-template-columns: 62px minmax(0, 1fr);
  gap: 2px 16px;
  align-items: baseline;
  padding: 16px 6px;
  border-bottom: 1px solid var(--line);
  transition: background-color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.page-about .about-crew__item:hover {
  background: var(--sand-100);
  border-bottom-color: var(--signal);
}

.page-about .about-crew__num {
  grid-row: 1 / span 2;
  font-family: var(--font-mono);
  font-size: clamp(20px, 3vw, 26px);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.03em;
  color: var(--signal);
}

.page-about .about-crew__title {
  font-size: clamp(18px, 2.4vw, 21px);
  font-weight: 800;
  letter-spacing: 0.01em;
}

.page-about .about-crew__text {
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
  max-width: 40em;
}

.page-about .about-figure {
  margin: clamp(26px, 4vw, 40px) 0 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  clip-path: polygon(0 0, 100% 0, 100% 100%, 48px 100%, 0 calc(100% - 48px));
  filter: saturate(0.92) contrast(1.05);
}

.page-about .about-figure figcaption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--ink-soft);
}

/* ---------- 三级校验 ---------- */
.page-about .about-flow {
  margin-top: clamp(18px, 3vw, 28px);
}

.page-about .about-flow__trace {
  display: block;
  width: 100%;
  height: auto;
  max-width: 720px;
  color: var(--sand-300);
  margin-bottom: clamp(8px, 2vw, 16px);
}

.page-about .about-flow__nodes {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .about-flow__node {
  background: var(--sand-50);
  border: 1px solid var(--line);
  border-top: 3px solid var(--indigo-950);
  padding: 15px 18px 17px;
  transition: border-color 0.18s var(--ease), box-shadow 0.18s var(--ease);
}

.page-about .about-flow__node:hover {
  border-top-color: var(--signal);
  box-shadow: var(--shadow-card);
}

.page-about .about-flow__node summary {
  display: flex;
  align-items: baseline;
  gap: 10px;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-display);
  font-size: clamp(17px, 2.2vw, 20px);
  font-weight: 800;
  color: var(--indigo-950);
}

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

.page-about .about-flow__node summary::marker {
  content: "";
}

.page-about .about-flow__node summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 500;
  color: var(--signal);
}

.page-about .about-flow__node[open] summary::after {
  content: "−";
}

.page-about .about-flow__num {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--signal);
}

.page-about .about-flow__node p {
  margin-top: 10px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
}

/* ---------- 发展节点 ---------- */
.page-about .about-years-head {
  display: grid;
  gap: clamp(16px, 3vw, 32px);
  align-items: end;
  margin-bottom: clamp(24px, 4vw, 44px);
}

.page-about .about-years__texture {
  display: block;
  width: 100%;
  max-width: 100%;
  height: 170px;
  object-fit: cover;
  clip-path: polygon(0 0, 100% 0, 100% 100%, 40px 100%, 0 calc(100% - 40px));
  filter: saturate(0.82) contrast(1.08);
}

.page-about .about-years {
  display: grid;
  gap: clamp(16px, 3vw, 34px);
}

.page-about .about-years__nav {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding-bottom: 6px;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-years__link {
  position: relative;
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--ink-soft);
  text-decoration: none;
  padding: 6px 11px;
  border: 1px solid var(--line);
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease), background-color 0.18s var(--ease);
}

.page-about .about-years__link:hover,
.page-about .about-years__link:focus-visible {
  color: var(--indigo-950);
  border-color: var(--signal);
  background: var(--sand-100);
}

.page-about .about-stage {
  padding: 14px 16px 18px;
  border-left: 3px solid var(--sand-300);
  scroll-margin-top: 96px;
  transition: background-color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.page-about .about-stage + .about-stage {
  margin-top: 6px;
}

.page-about .about-stage:hover {
  background: var(--sand-100);
}

.page-about .about-stage:target {
  border-left-color: var(--signal);
  background: var(--sand-100);
}

.page-about .about-stage__year {
  display: block;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--signal);
}

.page-about .about-stage__title {
  font-size: clamp(18px, 2.4vw, 22px);
  margin: 4px 0 8px;
}

.page-about .about-stage p {
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
  max-width: 42em;
}

/* ---------- 合作生态 ---------- */
.page-about .about-partners {
  list-style: none;
  margin: clamp(20px, 3vw, 30px) 0 0;
  padding: 0 0 14px;
  display: grid;
  gap: 14px;
}

.page-about .about-partner {
  position: relative;
  background: var(--sand-50);
  border: 1px solid var(--line);
  padding: 20px 20px 22px;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 18px), calc(100% - 18px) 100%, 0 100%);
  transition: background-color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.page-about .about-partner:hover,
.page-about .about-partner:focus-within {
  background: var(--indigo-950);
  border-color: var(--indigo-950);
}

.page-about .about-partner__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--signal);
  margin-bottom: 8px;
  transition: color 0.18s var(--ease);
}

.page-about .about-partner h3 {
  font-size: clamp(18px, 2.4vw, 22px);
  margin: 0 0 8px;
  transition: color 0.18s var(--ease);
}

.page-about .about-partner p {
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
  transition: color 0.18s var(--ease);
}

.page-about .about-partner:hover .about-partner__num,
.page-about .about-partner:focus-within .about-partner__num {
  color: var(--cyan);
}

.page-about .about-partner:hover h3,
.page-about .about-partner:focus-within h3 {
  color: var(--sand-50);
}

.page-about .about-partner:hover p,
.page-about .about-partner:focus-within p {
  color: rgba(246, 238, 223, 0.76);
}

/* ---------- 收尾 ---------- */
.page-about .about-close {
  position: relative;
  background: var(--indigo-950);
  color: var(--sand-50);
  padding: clamp(26px, 5vw, 56px);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 28px), calc(100% - 28px) 100%, 0 100%);
}

.page-about .about-close h2 {
  font-size: clamp(26px, 4.4vw, 40px);
  color: var(--sand-50);
  max-width: 21em;
}

.page-about .about-close__grid {
  display: grid;
  gap: clamp(18px, 3vw, 30px);
  margin-top: clamp(22px, 3.5vw, 36px);
}

.page-about .about-close__item h3 {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.16em;
  color: var(--cyan);
  margin: 0 0 8px;
}

.page-about .about-close__item p {
  font-size: 15px;
  line-height: 1.75;
  color: rgba(246, 238, 223, 0.78);
  margin: 0;
}

.page-about .about-close__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(24px, 4vw, 36px);
  padding-top: clamp(20px, 3vw, 28px);
  border-top: 1px solid rgba(246, 238, 223, 0.18);
}

.page-about .about-close__link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--sand-50);
  text-decoration: none;
  border: 1px solid rgba(246, 238, 223, 0.38);
  padding: 10px 18px;
  transition: border-color 0.18s var(--ease), color 0.18s var(--ease);
}

.page-about .about-close__link:hover,
.page-about .about-close__link:focus-visible {
  border-color: var(--cyan);
  color: var(--cyan);
}

/* ---------- 响应式 ---------- */
@media (min-width: 760px) {
  .page-about .about-partners {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 18px;
    padding-bottom: 40px;
  }

  .page-about .about-partner:nth-child(even) {
    transform: translateY(26px);
  }

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

@media (min-width: 860px) {
  .page-about .about-flow__nodes {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: clamp(16px, 2.4vw, 26px);
  }
}

@media (min-width: 880px) {
  .page-about .about-years-head {
    grid-template-columns: minmax(0, 1fr) clamp(200px, 22vw, 280px);
  }

  .page-about .about-years__texture {
    height: 220px;
  }

  .page-about .about-years {
    grid-template-columns: 116px minmax(0, 1fr);
    align-items: start;
  }

  .page-about .about-years__nav {
    flex-direction: column;
    overflow: visible;
    gap: 4px;
    padding-bottom: 0;
  }

  .page-about .about-years__link {
    justify-content: flex-start;
  }

  .page-about .about-years__link::after {
    content: attr(data-tip);
    position: absolute;
    left: calc(100% + 10px);
    top: 50%;
    transform: translateY(-50%) translateX(-4px);
    white-space: nowrap;
    background: var(--indigo-950);
    color: var(--sand-50);
    font-family: var(--font-body);
    font-size: 12px;
    font-weight: 400;
    letter-spacing: 0;
    line-height: 1.5;
    padding: 5px 10px;
    opacity: 0;
    visibility: hidden;
    z-index: 4;
    transition: opacity 0.16s var(--ease), transform 0.16s var(--ease), visibility 0.16s linear;
  }

  .page-about .about-years__link:hover::after,
  .page-about .about-years__link:focus-visible::after {
    opacity: 1;
    visibility: visible;
    transform: translateY(-50%) translateX(0);
  }
}

@media (min-width: 900px) {
  .page-about .about-split {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
  }

  .page-about .about-rail {
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
  }
}

@media (min-width: 960px) {
  .page-about .about-hero__layout {
    grid-template-columns: minmax(0, 1.04fr) minmax(0, 0.96fr);
    align-items: end;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-years__link::after,
  .page-about .about-years__link,
  .page-about .about-partner,
  .page-about .about-partner *,
  .page-about .about-crew__item,
  .page-about .about-stage,
  .page-about .about-flow__node,
  .page-about .about-flow__node summary::after,
  .page-about .about-close__link {
    transition: none;
  }

  .page-about .about-partner:nth-child(even) {
    transform: none;
  }
}