.page-about {
  --about-line-light: rgba(148, 163, 180, 0.22);
  --about-line-dark: rgba(18, 26, 36, 0.14);
  --about-muted-ink: #46566a;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-block: clamp(40px, 7vw, 88px) 0;
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(28px, 4vw, 56px);
  align-items: end;
}

.page-about .about-hero__aside {
  display: grid;
  gap: 18px;
  justify-items: start;
}

.page-about .about-hero__title {
  margin: 0;
  font-size: clamp(40px, 8.4vw, 104px);
  font-weight: 900;
  line-height: 1.02;
  letter-spacing: -0.02em;
  color: var(--board-050);
}

.page-about .about-hero__title span {
  display: block;
}

.page-about .about-hero__title span:last-child {
  color: var(--signal-500);
}

.page-about .about-hero__annotation {
  margin: 0;
  color: var(--haze-400);
}

.page-about .about-hero__main {
  display: grid;
  gap: 20px;
}

.page-about .about-hero__intro {
  margin: 0;
  max-width: 62ch;
  font-size: clamp(15px, 1.4vw, 17px);
  line-height: 1.85;
  color: var(--board-050);
}

.page-about .about-stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--glass-line);
  border: 1px solid var(--glass-line);
}

.page-about .about-stat {
  display: flex;
  flex-direction: column;
  gap: 6px;
  height: 100%;
  padding: 18px 16px;
  background: var(--abyss-950);
  color: var(--board-050);
  text-decoration: none;
  transition: background var(--t-base) var(--ease), transform var(--t-base) var(--ease);
}

.page-about .about-stat:hover,
.page-about .about-stat:focus-visible {
  background: var(--route-700);
  transform: translateY(-2px);
}

.page-about .about-stat__num {
  font-size: clamp(22px, 2.6vw, 30px);
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--signal-500);
}

.page-about .about-stat__label {
  font-size: 13px;
  line-height: 1.6;
  color: var(--haze-400);
}

.page-about .about-hero__figure {
  margin: clamp(32px, 5vw, 64px) 0 0;
  border: 1px solid var(--glass-line);
}

/* ---------- 章节头 ---------- */
.page-about .about-head {
  display: grid;
  gap: 14px;
  margin-bottom: clamp(28px, 4vw, 52px);
}

.page-about .about-head .section-no {
  font-size: clamp(30px, 4vw, 44px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--signal-500);
}

.page-about .about-head__text h2 {
  margin: 0 0 12px;
  font-size: clamp(26px, 3.6vw, 44px);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.01em;
  color: var(--board-050);
}

.page-about .about-head__text p {
  margin: 0;
  max-width: 64ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--haze-400);
}

.page-about .panel--board .about-head__text h2 {
  color: var(--ink-800);
}

.page-about .panel--board .about-head__text p {
  color: var(--about-muted-ink);
}

/* ---------- 发展节点时间线 ---------- */
.page-about .timeline {
  list-style: none;
  margin: 0 0 clamp(36px, 5vw, 60px);
  padding: 0 0 0 22px;
  border-left: 1px solid var(--steel-600);
}

.page-about .timeline__item {
  position: relative;
  padding-bottom: 30px;
}

.page-about .timeline__item:last-child {
  padding-bottom: 4px;
}

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: -27px;
  top: 8px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--electron-400);
  box-shadow: 0 0 0 4px rgba(34, 211, 208, 0.14);
  transition: transform var(--t-base) var(--ease), box-shadow var(--t-base) var(--ease);
}

.page-about .timeline__item:hover::before,
.page-about .timeline__item:focus-within::before {
  transform: scale(1.4);
  box-shadow: 0 0 0 7px rgba(34, 211, 208, 0.22);
}

.page-about .timeline__item--current::before {
  background: var(--signal-500);
  box-shadow: 0 0 0 4px rgba(255, 90, 31, 0.2);
}

.page-about .timeline__year {
  display: block;
  margin-bottom: 8px;
  font-size: clamp(22px, 2.8vw, 32px);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--board-050);
}

.page-about .timeline__body h3 {
  margin: 0 0 8px;
  font-size: 18px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--electron-400);
}

.page-about .timeline__body p {
  margin: 0;
  max-width: 60ch;
  font-size: 15px;
  line-height: 1.85;
  color: var(--haze-400);
}

.page-about .about-milestones__figure {
  margin: 0;
  border: 1px solid var(--glass-line);
}

.page-about .about-milestones__figure .media-caption {
  padding: 10px 2px 0;
  font-size: 12.5px;
  color: var(--haze-400);
}

/* ---------- 团队与分工 ---------- */
.page-about .about-team__grid {
  display: grid;
  gap: clamp(28px, 4vw, 48px);
}

.page-about .team-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .team-item {
  display: grid;
  gap: 6px;
  padding: 20px 14px;
  border-top: 1px solid var(--about-line-dark);
  text-decoration: none;
  color: inherit;
  transition: background var(--t-base) var(--ease), transform var(--t-base) var(--ease);
}

.page-about .team-list li:last-child .team-item {
  border-bottom: 1px solid var(--about-line-dark);
}

.page-about .team-item:hover,
.page-about .team-item:focus-visible {
  background: rgba(27, 58, 107, 0.07);
  transform: translateX(2px);
}

.page-about .team-item__role {
  font-size: 17px;
  font-weight: 700;
  color: var(--ink-800);
}

.page-about .team-item__count {
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: var(--signal-600);
}

.page-about .team-item__desc {
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--about-muted-ink);
}

.page-about .about-team__figure {
  margin: 0;
  border: 1px solid var(--about-line-dark);
}

.page-about .about-team__figure .media-caption {
  padding: 10px 2px 0;
  font-size: 12.5px;
  color: var(--about-muted-ink);
}

/* ---------- 交付环节 ---------- */
.page-about .stage-list {
  border-top: 1px solid var(--glass-line);
}

.page-about .stage {
  border-bottom: 1px solid var(--glass-line);
}

.page-about .stage summary {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 20px 4px;
  cursor: pointer;
  list-style: none;
  transition: background var(--t-base) var(--ease);
}

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

.page-about .stage summary:hover {
  background: rgba(244, 247, 250, 0.05);
}

.page-about .stage__no {
  flex: 0 0 auto;
  font-size: 13px;
  font-weight: 700;
  color: var(--signal-500);
}

.page-about .stage__title {
  flex: 1 1 auto;
  font-size: clamp(18px, 2.4vw, 24px);
  font-weight: 700;
  line-height: 1.25;
  color: var(--board-050);
}

.page-about .stage__hint {
  flex: 0 0 auto;
  font-size: 12px;
  color: var(--haze-400);
}

.page-about .stage summary::after {
  content: "＋";
  flex: 0 0 auto;
  font-size: 15px;
  line-height: 1;
  color: var(--electron-400);
}

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

.page-about .stage__panel {
  padding: 0 4px 26px;
}

.page-about .stage__panel p {
  margin: 0 0 18px;
  max-width: 70ch;
  font-size: 15px;
  line-height: 1.85;
  color: var(--haze-400);
}

.page-about .stage__dl {
  display: grid;
  gap: 4px 20px;
  margin: 0;
}

.page-about .stage__dl dt {
  font-size: 12.5px;
  letter-spacing: 0.08em;
  color: var(--electron-400);
}

.page-about .stage__dl dd {
  margin: 0 0 12px;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--board-050);
}

/* ---------- 合规与留档 ---------- */
.page-about .archive-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--about-line-dark);
  border: 1px solid var(--about-line-dark);
}

.page-about .archive-card {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 24px 20px;
  background: var(--board-050);
  transition: background var(--t-base) var(--ease), transform var(--t-base) var(--ease);
}

.page-about .archive-card:hover {
  background: #ffffff;
  transform: translateY(-2px);
}

.page-about .archive-card__tag {
  font-size: 11.5px;
  letter-spacing: 0.14em;
  color: var(--signal-600);
}

.page-about .archive-card h3 {
  margin: 0;
  font-size: 17px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--ink-800);
}

.page-about .archive-card p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--about-muted-ink);
}

/* ---------- 合作生态 ---------- */
.page-about .network-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--glass-line);
  border: 1px solid var(--glass-line);
}

.page-about .network-region {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 26px 22px;
  background: var(--abyss-950);
  transition: background var(--t-base) var(--ease);
}

.page-about .network-region:hover {
  background: var(--route-700);
}

.page-about .network-region h3 {
  margin: 0;
  font-size: 18px;
  font-weight: 700;
  color: var(--board-050);
}

.page-about .network-region p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--haze-400);
}

.page-about .network-note {
  margin: clamp(24px, 3vw, 36px) 0 0;
  max-width: 72ch;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--electron-400);
}

/* ---------- 服务理念与结尾 ---------- */
.page-about .creed-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 26px;
}

.page-about .creed-item {
  padding-top: 18px;
  border-top: 2px solid var(--signal-500);
}

.page-about .creed-item h3 {
  margin: 0 0 10px;
  font-size: 18px;
  font-weight: 700;
  color: var(--board-050);
}

.page-about .creed-item p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--haze-400);
}

.page-about .about-cta {
  margin-top: clamp(36px, 5vw, 64px);
  padding: clamp(24px, 3.5vw, 38px);
  border: 1px solid var(--glass-line);
  background: var(--glass-100);
  display: grid;
  gap: 22px;
}

.page-about .about-cta p {
  margin: 0;
  max-width: 60ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--board-050);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .stage__dl {
    grid-template-columns: 92px minmax(0, 1fr);
  }
}

@media (min-width: 760px) {
  .page-about .timeline__item {
    display: grid;
    grid-template-columns: 120px minmax(0, 1fr);
    gap: clamp(18px, 3vw, 40px);
    padding-bottom: 36px;
  }

  .page-about .timeline__year {
    margin-bottom: 0;
  }

  .page-about .stage__panel {
    padding-left: 56px;
  }

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

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

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
    gap: clamp(36px, 5vw, 80px);
  }

  .page-about .about-hero__aside {
    gap: 28px;
  }

  .page-about .about-hero__annotation {
    writing-mode: vertical-rl;
    letter-spacing: 0.32em;
    font-size: 12px;
    justify-self: end;
  }

  .page-about .about-head {
    grid-template-columns: 96px minmax(0, 1fr);
    gap: 32px;
    align-items: start;
  }

  .page-about .about-team__grid {
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .creed-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 36px;
  }
}

@media (min-width: 720px) {
  .page-about .team-item {
    grid-template-columns: minmax(150px, 190px) 96px minmax(0, 1fr);
    align-items: baseline;
    gap: 20px;
    padding: 22px 14px;
  }
}

@media (min-width: 1080px) {
  .page-about .archive-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

@media (prefers-reduced-motion: reduce) {
  .page-about .about-stat,
  .page-about .team-item,
  .page-about .archive-card,
  .page-about .network-region,
  .page-about .timeline__item::before {
    transition: none;
    transform: none;
  }
}
<<<END>>>