.page-about {
  background: var(--abyss-900);
  color: var(--text-100);
  padding-bottom: clamp(56px, 8vw, 104px);
}

.page-about .container {
  max-width: 1280px;
  margin: 0 auto;
  padding-inline: var(--pad);
}

/* 面包屑 */
.page-about .breadcrumb {
  padding-top: clamp(18px, 3vw, 28px);
}
.page-about .breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  list-style: none;
  margin: 0;
  padding: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--text-300);
}
.page-about .breadcrumb-list li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--steel-500);
}
.page-about .breadcrumb-list a {
  color: var(--text-300);
  text-decoration: none;
  border-bottom: 1px solid transparent;
}
.page-about .breadcrumb-list a:hover,
.page-about .breadcrumb-list a:focus-visible {
  color: var(--cyan-200);
  border-bottom-color: var(--cyan-400);
}

/* 开篇叙事 */
.page-about .about-intro {
  display: grid;
  gap: clamp(24px, 4vw, 48px);
  padding-block: clamp(28px, 5vw, 56px) clamp(40px, 6vw, 72px);
  border-bottom: 1px solid var(--line-600);
}
.page-about .intro-kicker {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--cyan-400);
}
.page-about .about-intro h1 {
  margin: 0 0 22px;
  font-family: var(--font-display);
  font-weight: 900;
  font-stretch: condensed;
  font-size: clamp(30px, 7vw, 56px);
  line-height: 1.08;
  letter-spacing: -.02em;
  color: var(--text-100);
}
.page-about .intro-lede {
  margin: 0 0 20px;
  padding-left: 16px;
  border-left: 2px solid var(--cyan-400);
  font-size: clamp(16px, 2vw, 19px);
  line-height: 1.78;
  color: var(--cyan-200);
}
.page-about .intro-copy p {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.78;
  color: var(--text-300);
  max-width: 40em;
}
.page-about .intro-copy p:last-child {
  margin-bottom: 0;
}
.page-about .intro-figure {
  margin: 0;
}
.page-about .media-frame img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border-radius: var(--radius);
}
.page-about .media-caption {
  margin-top: 10px;
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--text-300);
}

/* 章节通用 */
.page-about .about-section {
  padding-block: clamp(44px, 7vw, 88px);
  border-bottom: 1px solid var(--line-600);
}
.page-about .about-section:last-of-type {
  border-bottom: 0;
}
.page-about .section-head {
  margin-bottom: clamp(24px, 4vw, 40px);
}
.page-about .section-index {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--cyan-400);
}
.page-about .section-title {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-weight: 900;
  font-stretch: condensed;
  font-size: clamp(23px, 4vw, 40px);
  line-height: 1.14;
  letter-spacing: -.02em;
  color: var(--text-100);
}
.page-about .section-sub {
  margin: 0;
  max-width: 62ch;
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--text-300);
}

/* 时间轴 */
.page-about .timeline-lead {
  margin: 0 0 clamp(28px, 4vw, 44px);
  position: relative;
  overflow: hidden;
  border-radius: var(--radius);
  border: 1px solid var(--line-600);
}
.page-about .timeline-lead img {
  border-radius: 0;
}
.page-about .tl {
  list-style: none;
  margin: 0;
  padding: 0 0 0 32px;
  position: relative;
}
.page-about .tl::before {
  content: "";
  position: absolute;
  left: 10px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan-400) 0%, var(--line-600) 22%, var(--line-600) 88%, transparent 100%);
}
.page-about .tl-item {
  position: relative;
  margin-bottom: 22px;
}
.page-about .tl-item:last-child {
  margin-bottom: 0;
}
.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: -28px;
  top: 24px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--abyss-900);
  border: 2px solid var(--cyan-400);
  box-shadow: 0 0 0 4px rgba(0, 229, 208, .08);
}
.page-about .tl-card {
  position: relative;
  overflow: hidden;
  padding: 20px 18px 22px;
  background: var(--panel-700);
  border: 1px solid var(--line-600);
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
  transition: border-color .24s var(--ease-out), transform .24s var(--ease-out);
}
.page-about .tl-card:hover {
  border-color: var(--steel-500);
  transform: translateY(-2px);
}
.page-about .tl-year {
  position: absolute;
  right: 6px;
  top: -14px;
  font-family: var(--font-display);
  font-weight: 900;
  font-stretch: condensed;
  font-size: clamp(56px, 12vw, 96px);
  line-height: 1;
  letter-spacing: -.04em;
  color: rgba(45, 92, 130, .32);
  pointer-events: none;
  user-select: none;
  transition: color .24s var(--ease-out);
}
.page-about .tl-card:hover .tl-year {
  color: rgba(0, 229, 208, .22);
}
.page-about .tl-phase {
  position: relative;
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--cyan-400);
}
.page-about .tl-card h3 {
  position: relative;
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(18px, 2.4vw, 23px);
  line-height: 1.28;
  letter-spacing: -.01em;
  color: var(--text-100);
}
.page-about .tl-card p:not(.tl-phase) {
  position: relative;
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--text-300);
  max-width: 42em;
}

/* 团队分工 */
.page-about .team-grid {
  display: grid;
  gap: clamp(24px, 4vw, 44px);
}
.page-about .donut-wrap {
  position: relative;
  display: grid;
  place-items: center;
  padding: clamp(16px, 3vw, 28px);
  background: var(--grad-signal);
  border: 1px solid var(--line-600);
  border-radius: var(--radius);
}
.page-about .donut {
  width: min(260px, 62vw);
  height: auto;
  display: block;
}
.page-about .donut circle {
  fill: none;
  stroke-width: 12;
}
.page-about .donut-track {
  stroke: var(--line-600);
}
.page-about .donut-seg {
  transition: stroke-width .2s var(--ease-out), opacity .2s var(--ease-out);
}
.page-about .donut-seg--a {
  stroke: var(--cyan-400);
  stroke-dasharray: 111.6 152.3;
  stroke-dashoffset: 0;
}
.page-about .donut-seg--b {
  stroke: var(--steel-500);
  stroke-dasharray: 60.9 203;
  stroke-dashoffset: -111.6;
}
.page-about .donut-seg--c {
  stroke: var(--cyan-200);
  stroke-dasharray: 50.8 213.1;
  stroke-dashoffset: -172.5;
}
.page-about .donut-seg--d {
  stroke: var(--orange-500);
  stroke-dasharray: 40.6 223.3;
  stroke-dashoffset: -223.3;
}
.page-about .donut-seg:hover {
  stroke-width: 17;
}
.page-about .donut-center {
  position: absolute;
  margin: 0;
  text-align: center;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--text-300);
}
.page-about .donut-center span {
  display: block;
  font-family: var(--font-display);
  font-weight: 900;
  font-stretch: condensed;
  font-size: clamp(30px, 6vw, 42px);
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--cyan-400);
  margin-bottom: 4px;
}
.page-about .team-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}
.page-about .team-item {
  display: grid;
  grid-template-columns: 6px minmax(0, 1fr);
  gap: 12px;
  padding: 14px 16px;
  background: var(--abyss-800);
  border: 1px solid var(--line-600);
  border-radius: var(--radius);
}
.page-about .team-swatch {
  width: 6px;
  height: 100%;
  min-height: 34px;
  border-radius: 2px;
}
.page-about .team-swatch--a { background: var(--cyan-400); }
.page-about .team-swatch--b { background: var(--steel-500); }
.page-about .team-swatch--c { background: var(--cyan-200); }
.page-about .team-swatch--d { background: var(--orange-500); }
.page-about .team-item h3 {
  margin: 0 0 6px;
  font-size: 16px;
  font-weight: 700;
  color: var(--text-100);
}
.page-about .team-count {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 400;
  letter-spacing: .04em;
  color: var(--cyan-200);
  margin-left: 6px;
}
.page-about .team-item p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--text-300);
}

/* 发布流程 */
.page-about .pipeline-grid {
  display: grid;
  gap: clamp(24px, 4vw, 40px);
}
.page-about .pipeline-steps {
  min-width: 0;
}
.page-about .panel {
  margin-bottom: 12px;
  background: var(--panel-700);
  border: 1px solid var(--line-600);
  border-radius: var(--radius);
  overflow: hidden;
}
.page-about .panel summary {
  position: relative;
  padding: 15px 46px 15px 16px;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 17px;
  letter-spacing: -.01em;
  color: var(--text-100);
}
.page-about .panel summary::-webkit-details-marker {
  display: none;
}
.page-about .panel summary::after {
  content: "+";
  position: absolute;
  right: 16px;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-mono);
  font-size: 18px;
  color: var(--orange-500);
}
.page-about .panel[open] summary::after {
  content: "–";
}
.page-about .panel summary:focus-visible {
  outline: 2px solid var(--cyan-400);
  outline-offset: -2px;
}
.page-about .step-no {
  margin-right: 10px;
  color: var(--cyan-400);
  font-size: 13px;
}
.page-about .panel-body {
  padding: 0 16px 18px;
  font-size: 15px;
  line-height: 1.78;
  color: var(--text-300);
  border-top: 1px solid var(--line-600);
  padding-top: 14px;
  margin-top: 2px;
}
.page-about .panel-body p {
  margin: 0 0 10px;
}
.page-about .panel-body ul {
  margin: 0;
  padding-left: 18px;
}
.page-about .panel-body li {
  margin-bottom: 6px;
  font-size: 14.5px;
}
.page-about .panel-body li:last-child {
  margin-bottom: 0;
}
.page-about .pipeline-figure {
  margin: 0;
}
.page-about .pipeline-figure img {
  border: 1px solid var(--line-600);
}

/* 合作生态 */
.page-about .partner-grid {
  display: grid;
  gap: clamp(24px, 4vw, 40px);
}
.page-about .partner-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}
.page-about .partner-list li {
  padding-left: 16px;
  border-left: 1px solid var(--line-600);
  font-size: 15px;
  line-height: 1.78;
  color: var(--text-300);
}
.page-about .partner-list strong {
  display: block;
  margin-bottom: 4px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 16.5px;
  letter-spacing: -.01em;
  color: var(--text-100);
}
.page-about .partner-map {
  margin: 0;
  padding: clamp(14px, 3vw, 24px);
  background: var(--abyss-800);
  border: 1px solid var(--line-600);
  border-radius: var(--radius);
}
.page-about .partner-map svg {
  display: block;
  width: 100%;
  height: auto;
}
.page-about .map-dot {
  fill: var(--steel-500);
  opacity: .6;
}
.page-about .map-dot--on {
  fill: var(--cyan-400);
  opacity: 1;
}
.page-about .map-dot--hot {
  fill: var(--orange-500);
  opacity: 1;
}

/* 规划 */
.page-about .next-grid {
  display: grid;
  gap: 14px;
  margin-bottom: clamp(28px, 4vw, 44px);
}
.page-about .next-card {
  padding: 18px 18px 20px;
  background: var(--abyss-800);
  border: 1px solid var(--line-600);
  border-top: 2px solid var(--cyan-400);
  border-radius: var(--radius);
}
.page-about .next-no {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .1em;
  color: var(--cyan-400);
}
.page-about .next-card h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 17px;
  letter-spacing: -.01em;
  color: var(--text-100);
}
.page-about .next-card p:not(.next-no) {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--text-300);
}

.page-about .about-cta {
  display: grid;
  gap: 18px;
  padding: clamp(22px, 4vw, 34px);
  background: var(--grad-signal);
  border: 1px solid var(--line-600);
  border-radius: var(--radius);
}
.page-about .about-cta p {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--text-100);
  max-width: 46em;
}
.page-about .cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

/* 断点：平板 */
@media (min-width: 768px) {
  .page-about .next-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .about-cta {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
  }
  .page-about .cta-actions {
    justify-content: flex-end;
  }
}

/* 断点：桌面，时间轴交替 */
@media (min-width: 900px) {
  .page-about .about-intro {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, .85fr);
    align-items: start;
  }
  .page-about .intro-figure {
    position: sticky;
    top: calc(var(--bar-h) + 24px);
  }
  .page-about .team-grid {
    grid-template-columns: minmax(0, .82fr) minmax(0, 1.18fr);
    align-items: center;
  }
  .page-about .pipeline-grid {
    grid-template-columns: minmax(0, 1.25fr) minmax(0, .75fr);
    align-items: start;
  }
  .page-about .pipeline-figure {
    position: sticky;
    top: calc(var(--bar-h) + 24px);
  }
  .page-about .partner-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: center;
  }

  .page-about .tl {
    padding-left: 0;
  }
  .page-about .tl::before {
    left: 50%;
    top: 4px;
    bottom: 4px;
  }
  .page-about .tl-item {
    width: calc(50% - 32px);
    margin-bottom: 32px;
  }
  .page-about .tl-item:nth-child(odd)::before {
    left: auto;
    right: -38px;
  }
  .page-about .tl-item:nth-child(even) {
    margin-left: calc(50% + 32px);
  }
  .page-about .tl-item:nth-child(even)::before {
    left: -38px;
    right: auto;
  }
  .page-about .tl-card {
    padding: 22px 22px 24px;
  }
  .page-about .tl-item:nth-child(odd) .tl-card {
    text-align: right;
  }
  .page-about .tl-item:nth-child(odd) .tl-card p:not(.tl-phase) {
    margin-left: auto;
  }
  .page-about .tl-item:nth-child(odd) .tl-year {
    right: auto;
    left: 6px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .tl-card,
  .page-about .tl-year,
  .page-about .donut-seg {
    transition: none;
  }
  .page-about .tl-card:hover {
    transform: none;
  }
}
<<<PAGE_CSS_DONE>>>
</main>