.page-about {
  --about-rail-w: 196px;
  --about-line: var(--og-line);
  padding-bottom: 72px;
  background: var(--og-void);
  color: var(--og-text);
}

/* 面包屑 */
.page-about .og-breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 0;
  padding-top: 12px;
  font-family: var(--og-font-mono);
  font-size: var(--og-fs-12);
  letter-spacing: 0.04em;
  color: var(--og-muted);
}
.page-about .og-breadcrumb__item {
  color: var(--og-muted);
  text-decoration: none;
}
.page-about .og-breadcrumb__item + .og-breadcrumb__item::before {
  content: "/";
  margin: 0 8px;
  color: var(--og-line);
}
.page-about .og-breadcrumb__item:last-child {
  color: var(--og-cyan);
}

/* 首屏 */
.page-about .about-hero {
  padding-top: 18px;
}
.page-about .og-kicker {
  margin: 0;
  font-family: var(--og-font-mono);
  font-size: var(--og-fs-12);
  letter-spacing: 0.14em;
  color: var(--og-amber);
  border-left: 2px solid var(--og-amber);
  padding-left: 10px;
  text-transform: uppercase;
}
.page-about .about-hero__title {
  margin: 14px 0 14px;
  font-size: var(--og-fs-40);
  font-weight: 900;
  line-height: 1.16;
  letter-spacing: -0.02em;
}
.page-about .about-hero__lead {
  margin: 0;
  max-width: 62ch;
  font-size: var(--og-fs-16);
  line-height: 1.8;
  color: var(--og-muted);
}
.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
}
.page-about .about-stat {
  padding: 12px 14px;
  background: var(--og-panel);
  border: 2px solid var(--about-line);
}
.page-about .about-stat__num {
  display: block;
  font-family: var(--og-font-mono);
  font-size: var(--og-fs-28);
  line-height: 1.1;
  letter-spacing: 0.02em;
  color: var(--og-cyan);
}
.page-about .about-stat__label {
  display: block;
  margin-top: 6px;
  font-size: var(--og-fs-12);
  line-height: 1.6;
  color: var(--og-muted);
}
.page-about .about-hero__media {
  position: relative;
  margin-top: 22px;
  border: 2px solid var(--about-line);
  box-shadow: var(--og-shadow);
  overflow: hidden;
}
.page-about .about-hero__media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(1.05) contrast(1.05);
}
.page-about .about-hero__media::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: repeating-linear-gradient(to bottom, rgba(53, 227, 210, 0.06) 0 1px, transparent 1px 4px);
}

/* 章节索引 + 正文 */
.page-about .about-layout {
  margin-top: 34px;
}
.page-about .about-rail {
  margin-bottom: 22px;
  border-top: 2px solid var(--about-line);
  padding-top: 10px;
}
.page-about .about-rail__title {
  margin: 0 0 8px;
  font-family: var(--og-font-mono);
  font-size: var(--og-fs-12);
  letter-spacing: 0.16em;
  color: var(--og-rust);
}
.page-about .about-rail__list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 8px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}
.page-about .about-rail__item {
  flex: 0 0 auto;
}
.page-about .about-rail__link {
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 8px 12px;
  background: var(--og-panel);
  border: 2px solid var(--about-line);
  color: var(--og-muted);
  text-decoration: none;
  font-size: var(--og-fs-14);
  white-space: nowrap;
  transition: border-color 140ms ease, color 140ms ease, box-shadow 140ms ease;
}
.page-about .about-rail__num {
  font-family: var(--og-font-mono);
  font-size: var(--og-fs-12);
  letter-spacing: 0.06em;
  color: var(--og-rust);
}
.page-about .about-rail__link:hover,
.page-about .about-rail__link:focus-visible {
  color: var(--og-text);
  border-color: var(--og-cyan);
  box-shadow: 3px 3px 0 rgba(53, 227, 210, 0.35);
  outline: none;
}

/* 区块通用 */
.page-about .about-sec + .about-sec {
  margin-top: 46px;
}
.page-about .about-sec__head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--about-line);
}
.page-about .about-sec__num {
  font-family: var(--og-font-mono);
  font-size: var(--og-fs-20);
  letter-spacing: 0.06em;
  color: var(--og-rust);
}
.page-about .about-sec__title {
  margin: 0;
  font-size: var(--og-fs-28);
  font-weight: 800;
  line-height: 1.3;
  letter-spacing: -0.01em;
}
.page-about .about-sec__lead {
  margin: 16px 0 0;
  max-width: 64ch;
  font-size: var(--og-fs-16);
  line-height: 1.8;
  color: var(--og-muted);
}

/* 公平原则 */
.page-about .principle {
  display: grid;
  gap: 14px;
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
}
.page-about .principle__item {
  position: relative;
  padding: 18px 18px 18px 20px;
  background: var(--og-panel);
  border: 2px solid var(--about-line);
  border-left: 4px solid var(--og-cyan);
}
.page-about .principle__n {
  display: block;
  font-family: var(--og-font-mono);
  font-size: var(--og-fs-12);
  letter-spacing: 0.12em;
  color: var(--og-rust);
}
.page-about .principle__title {
  margin: 6px 0 8px;
  font-size: var(--og-fs-20);
  font-weight: 800;
  line-height: 1.35;
}
.page-about .principle__text {
  margin: 0;
  font-size: var(--og-fs-16);
  line-height: 1.8;
  color: var(--og-muted);
}
.page-about .principle__do {
  margin: 12px 0 0;
  padding-left: 12px;
  border-left: 2px solid var(--og-magenta);
  font-family: var(--og-font-mono);
  font-size: var(--og-fs-12);
  line-height: 1.7;
  letter-spacing: 0.02em;
  color: var(--og-cyan);
}
.page-about .about-quote {
  position: relative;
  margin: 22px 0 0;
  padding: 22px 20px 22px 26px;
  background: var(--og-cream);
  color: var(--og-brown);
  border: 2px solid var(--og-brown);
  box-shadow: 4px 4px 0 var(--og-line);
  font-size: var(--og-fs-20);
  font-weight: 700;
  line-height: 1.65;
}
.page-about .about-quote::before {
  content: "\201C";
  position: absolute;
  left: 8px;
  top: 8px;
  font-family: var(--og-font-mono);
  font-size: var(--og-fs-28);
  line-height: 1;
  color: var(--og-rust);
}

/* 技术底座 */
.page-about .stack-figure {
  margin: 22px 0 0;
  padding: 12px;
  border: 2px solid var(--about-line);
  background:
    radial-gradient(circle at 50% 0%, rgba(53, 227, 210, 0.08), transparent 62%),
    var(--og-panel);
}
.page-about .stack-svg {
  display: block;
  width: 100%;
  height: auto;
}
.page-about .stack-svg a {
  text-decoration: none;
}
.page-about .stack-svg__shape {
  stroke-width: 2;
  fill-opacity: 0.14;
  transition: fill-opacity 140ms ease, stroke 140ms ease;
}
.page-about .stack-svg a:hover .stack-svg__shape,
.page-about .stack-svg a:focus-visible .stack-svg__shape {
  fill-opacity: 0.34;
}
.page-about .stack-svg a:focus-visible {
  outline: none;
}
.page-about .stack-svg__shape--node {
  fill: var(--og-cyan);
  stroke: var(--og-cyan);
}
.page-about .stack-svg__shape--platform {
  fill: var(--og-cyan);
  stroke: var(--og-cyan);
}
.page-about .stack-svg__shape--security {
  fill: var(--og-magenta);
  stroke: var(--og-magenta);
}
.page-about .stack-svg__shape--archive {
  fill: var(--og-amber);
  stroke: var(--og-amber);
}
.page-about .stack-svg__text {
  fill: var(--og-text);
  font-family: var(--og-font-mono);
  font-size: 15px;
  letter-spacing: 0.08em;
}
.page-about .stack-svg__axis {
  fill: var(--og-muted);
  font-family: var(--og-font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
}
.page-about .stack-list {
  display: grid;
  gap: 14px;
  margin-top: 18px;
}
.page-about .stack-layer {
  padding: 16px 18px;
  background: var(--og-panel);
  border: 2px solid var(--about-line);
  scroll-margin-top: 110px;
}
.page-about .stack-layer--node { border-left: 4px solid var(--og-cyan); }
.page-about .stack-layer--platform { border-left: 4px solid var(--og-cyan); }
.page-about .stack-layer--security { border-left: 4px solid var(--og-magenta); }
.page-about .stack-layer--archive { border-left: 4px solid var(--og-amber); }
.page-about .stack-layer__tag {
  display: inline-block;
  font-family: var(--og-font-mono);
  font-size: var(--og-fs-12);
  letter-spacing: 0.12em;
  color: var(--og-amber);
}
.page-about .stack-layer__title {
  margin: 6px 0 8px;
  font-size: var(--og-fs-20);
  font-weight: 800;
  line-height: 1.35;
}
.page-about .stack-layer__text {
  margin: 0;
  font-size: var(--og-fs-16);
  line-height: 1.8;
  color: var(--og-muted);
}

/* 团队 */
.page-about .team-grid {
  display: grid;
  gap: 14px;
  margin-top: 22px;
}
.page-about .team-card {
  padding: 18px;
  background: var(--og-panel);
  border: 2px solid var(--about-line);
  box-shadow: 4px 4px 0 rgba(35, 42, 56, 0.9);
}
.page-about .team-card:nth-child(2) {
  border-color: var(--og-magenta);
}
.page-about .team-card__tag {
  display: inline-block;
  padding: 2px 8px;
  font-family: var(--og-font-mono);
  font-size: var(--og-fs-12);
  letter-spacing: 0.1em;
  color: var(--og-void);
  background: var(--og-cyan);
}
.page-about .team-card:nth-child(2) .team-card__tag {
  background: var(--og-magenta);
  color: var(--og-text);
}
.page-about .team-card__title {
  margin: 10px 0 8px;
  font-size: var(--og-fs-20);
  font-weight: 800;
  line-height: 1.35;
}
.page-about .team-card__text {
  margin: 0;
  font-size: var(--og-fs-16);
  line-height: 1.8;
  color: var(--og-muted);
}
.page-about .team-media {
  margin-top: 18px;
  border: 2px solid var(--about-line);
  overflow: hidden;
}
.page-about .team-media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* 时间线 */
.page-about .timeline {
  margin: 22px 0 0;
  padding: 0 0 0 18px;
  list-style: none;
  border-left: 2px solid var(--about-line);
}
.page-about .timeline__item {
  position: relative;
  padding-bottom: 12px;
}
.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: -25px;
  top: 16px;
  width: 10px;
  height: 10px;
  background: var(--og-void);
  border: 2px solid var(--og-cyan);
}
.page-about .timeline__det {
  border: 2px solid var(--about-line);
  background: var(--og-panel);
}
.page-about .timeline__det[open] {
  border-color: var(--og-cyan);
  box-shadow: 4px 4px 0 rgba(53, 227, 210, 0.28);
}
.page-about .timeline__sum {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px;
  padding: 12px 14px;
  cursor: pointer;
  list-style: none;
}
.page-about .timeline__sum::-webkit-details-marker {
  display: none;
}
.page-about .timeline__sum::after {
  content: "+";
  margin-left: auto;
  font-family: var(--og-font-mono);
  font-size: var(--og-fs-16);
  color: var(--og-rust);
}
.page-about .timeline__det[open] .timeline__sum::after {
  content: "\2212";
  color: var(--og-cyan);
}
.page-about .timeline__ver {
  padding: 2px 8px;
  font-family: var(--og-font-mono);
  font-size: var(--og-fs-12);
  letter-spacing: 0.08em;
  color: var(--og-amber);
  border: 1px solid var(--og-amber);
}
.page-about .timeline__name {
  font-size: var(--og-fs-16);
  font-weight: 800;
  color: var(--og-text);
}
.page-about .timeline__body {
  margin: 0;
  padding: 0 14px 14px;
  font-size: var(--og-fs-14);
  line-height: 1.8;
  color: var(--og-muted);
}

/* 城市伙伴 */
.page-about .partner-grid {
  display: grid;
  gap: 16px;
  margin-top: 22px;
}
.page-about .partner-list {
  display: grid;
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}
.page-about .partner-item {
  padding: 16px 18px;
  background: var(--og-panel);
  border: 2px solid var(--about-line);
}
.page-about .partner-item__title {
  margin: 0 0 8px;
  font-size: var(--og-fs-20);
  font-weight: 800;
  line-height: 1.35;
  color: var(--og-text);
}
.page-about .partner-item__title::before {
  content: "";
  display: inline-block;
  width: 10px;
  height: 10px;
  margin-right: 10px;
  background: var(--og-magenta);
  vertical-align: middle;
}
.page-about .partner-item__text {
  margin: 0;
  font-size: var(--og-fs-16);
  line-height: 1.8;
  color: var(--og-muted);
}
.page-about .partner-media {
  margin: 0;
  border: 2px solid var(--about-line);
  background: var(--og-panel);
}
.page-about .partner-media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}
.page-about .partner-media figcaption {
  padding: 10px 14px;
  font-family: var(--og-font-mono);
  font-size: var(--og-fs-12);
  line-height: 1.7;
  letter-spacing: 0.02em;
  color: var(--og-muted);
  border-top: 2px solid var(--about-line);
}

/* 生态合作 */
.page-about .eco-grid {
  display: grid;
  gap: 14px;
  margin-top: 22px;
}
.page-about .eco-card {
  padding: 18px;
  background: var(--og-panel);
  border: 2px solid var(--about-line);
  border-top: 4px solid var(--og-magenta);
}
.page-about .eco-card:last-child {
  border-top-color: var(--og-cyan);
}
.page-about .eco-card__title {
  margin: 0 0 10px;
  font-size: var(--og-fs-20);
  font-weight: 800;
  line-height: 1.35;
}
.page-about .eco-card__text {
  margin: 0;
  font-size: var(--og-fs-16);
  line-height: 1.8;
  color: var(--og-muted);
}

/* 收尾 */
.page-about .about-cta {
  margin-top: 24px;
  padding: 22px 20px;
  border: 2px solid var(--og-cyan);
  background:
    linear-gradient(125deg, rgba(53, 227, 210, 0.14), rgba(255, 61, 154, 0.12) 70%, transparent),
    var(--og-panel);
}
.page-about .about-cta__title {
  margin: 0 0 8px;
  font-size: var(--og-fs-28);
  font-weight: 800;
  line-height: 1.3;
}
.page-about .about-cta__text {
  margin: 0;
  font-size: var(--og-fs-16);
  line-height: 1.8;
  color: var(--og-text);
}
.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 16px;
}
.page-about .about-cta__actions .og-btn {
  text-decoration: none;
}

/* 桌面 */
@media (min-width: 720px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .team-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .eco-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 960px) {
  .page-about {
    padding-bottom: 96px;
  }
  .page-about .about-hero__title {
    font-size: var(--og-fs-64);
    max-width: 18ch;
  }
  .page-about .about-layout {
    display: grid;
    grid-template-columns: var(--about-rail-w) minmax(0, 1fr);
    gap: 44px;
    align-items: start;
    margin-top: 52px;
  }
  .page-about .about-rail {
    position: sticky;
    top: 96px;
    margin-bottom: 0;
    border-top: 0;
    border-left: 2px solid var(--about-line);
    padding: 4px 0 0 16px;
  }
  .page-about .about-rail__list {
    flex-direction: column;
    gap: 4px;
    overflow: visible;
    padding-bottom: 0;
  }
  .page-about .about-rail__link {
    background: transparent;
    border: 0;
    border-left: 2px solid transparent;
    margin-left: -18px;
    padding: 8px 0 8px 16px;
    font-size: var(--og-fs-14);
  }
  .page-about .about-rail__link:hover,
  .page-about .about-rail__link:focus-visible {
    border-left-color: var(--og-cyan);
    color: var(--og-cyan);
    box-shadow: none;
  }
  .page-about .about-sec + .about-sec {
    margin-top: 64px;
  }
  .page-about .about-sec__title {
    font-size: var(--og-fs-40);
  }
  .page-about .principle {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .stack-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .partner-grid {
    grid-template-columns: 1.1fr 0.9fr;
    align-items: start;
  }
  .page-about .about-quote {
    font-size: var(--og-fs-28);
  }
}

@media (min-width: 1180px) {
  .page-about .about-hero__lead {
    font-size: var(--og-fs-20);
  }
  .page-about .team-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about * {
    transition-duration: 1ms !important;
    animation-duration: 1ms !important;
  }
}
</main>