.page-about {
  --about-toc-w: 208px;
  --about-panel-bg: rgba(7, 42, 46, 0.72);
  position: relative;
  color: var(--mist);
  background:
    radial-gradient(900px 520px at 84% -10%, rgba(53, 242, 208, 0.13), transparent 62%),
    radial-gradient(760px 480px at 2% 32%, rgba(92, 32, 56, 0.26), transparent 68%),
    radial-gradient(680px 420px at 60% 96%, rgba(26, 23, 56, 0.6), transparent 70%),
    var(--ink);
  padding-top: clamp(14px, 2.6vw, 28px);
  padding-bottom: clamp(56px, 9vw, 104px);
  overflow-x: clip;
}

.page-about a {
  color: var(--cyan);
}

/* 首屏 */
.page-about .about-hero {
  margin-top: clamp(16px, 2.4vw, 28px);
}

.page-about .about-hero__frame {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 36px);
  padding: clamp(20px, 4vw, 30px);
  border-radius: var(--radius);
  background:
    linear-gradient(158deg, rgba(7, 42, 46, 0.94) 0%, rgba(6, 19, 33, 0.97) 62%, rgba(26, 23, 56, 0.9) 100%);
  box-shadow: inset 0 0 0 1px rgba(30, 90, 99, 0.35);
}

.page-about .about-hero__copy {
  min-width: 0;
}

.page-about .about-hero__copy .display-1 {
  margin: 14px 0 18px;
  max-width: 15ch;
  line-height: 1.08;
}

.page-about .about-hero__copy .lead {
  max-width: 46ch;
  color: var(--mist);
  opacity: 0.88;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 14px;
  margin: 26px 0 0;
  padding: 20px 0 0;
  list-style: none;
  border-top: 1px solid var(--line-soft);
}

.page-about .about-hero__facts .stat {
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-width: 0;
}

.page-about .about-hero__facts .stat-value {
  font-size: clamp(22px, 2.8vw, 30px);
  line-height: 1.05;
  color: var(--cyan);
  letter-spacing: 0.01em;
}

.page-about .about-hero__facts .stat-label {
  font-size: 12.5px;
  line-height: 1.55;
  color: var(--cloud);
}

.page-about .about-hero__media {
  aspect-ratio: 14 / 9;
  border-radius: calc(var(--radius) - 2px);
  border: 1px solid var(--line-soft);
  background: linear-gradient(150deg, rgba(26, 23, 56, 0.85), rgba(7, 42, 46, 0.85));
}

/* 主体两栏 */
.page-about .about-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(18px, 3vw, 40px);
  margin-top: clamp(32px, 5vw, 64px);
}

.page-about .about-toc {
  min-width: 0;
  padding: 16px 18px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: rgba(7, 42, 46, 0.5);
}

.page-about .about-toc__label {
  margin: 0 0 10px;
  font-size: 11.5px;
  letter-spacing: 0.18em;
  color: var(--orange);
  text-transform: uppercase;
}

.page-about .about-toc__list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 4px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-toc__link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border: 1px solid var(--line-soft);
  border-radius: 999px;
  color: var(--cloud);
  font-size: 13.5px;
  white-space: nowrap;
  text-decoration: none;
  transition: color 180ms var(--ease), border-color 180ms var(--ease), background 180ms var(--ease);
}

.page-about .about-toc__link:hover,
.page-about .about-toc__link:focus-visible {
  color: var(--mist);
  border-color: var(--cyan);
  background: rgba(53, 242, 208, 0.1);
}

.page-about .about-toc__num {
  font-size: 11px;
  color: var(--cyan);
}

.page-about .about-toc__note {
  margin: 14px 0 0;
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--cloud);
}

.page-about .about-stream {
  min-width: 0;
}

/* 章节 */
.page-about .about-sec {
  padding-block: clamp(30px, 4.4vw, 52px);
  scroll-margin-top: calc(var(--bar-h) + 24px);
}

.page-about .about-sec + .about-sec {
  border-top: 1px solid var(--line-soft);
}

.page-about .about-sec__head {
  max-width: 62ch;
}

.page-about .about-sec__head .display-2 {
  margin: 12px 0 0;
  line-height: 1.12;
}

.page-about .about-sec__head .lead {
  margin-top: 16px;
  color: var(--mist);
  opacity: 0.84;
}

.page-about .about-prose {
  margin-top: 20px;
  max-width: 68ch;
  color: var(--mist);
  opacity: 0.9;
}

.page-about .about-prose p {
  margin: 0 0 16px;
}

.page-about .about-prose p:last-child {
  margin-bottom: 0;
}

.page-about .about-quote {
  margin: 26px 0 0;
  padding: 20px 22px 20px 24px;
  border-left: 3px solid var(--orange);
  border-radius: 0 var(--radius) var(--radius) 0;
  background: linear-gradient(100deg, rgba(92, 32, 56, 0.55), rgba(26, 23, 56, 0.25));
}

.page-about .about-quote p {
  margin: 0;
  font-size: clamp(17px, 1.9vw, 21px);
  line-height: 1.6;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--mist);
}

/* 四步方法 */
.page-about .about-steps {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
  counter-reset: none;
}

.page-about .about-step {
  position: relative;
  overflow: hidden;
  padding: 20px 20px 22px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: linear-gradient(152deg, rgba(7, 42, 46, 0.95), rgba(18, 23, 56, 0.6));
  transition: border-color 200ms var(--ease), transform 200ms var(--ease);
}

.page-about .about-step::before {
  content: "";
  position: absolute;
  top: -46px;
  right: -42px;
  width: 132px;
  height: 132px;
  border-radius: 46% 54% 62% 38% / 48% 40% 60% 52%;
  background: rgba(53, 242, 208, 0.12);
  pointer-events: none;
}

.page-about .about-step:nth-child(3)::before {
  background: rgba(92, 32, 56, 0.42);
}

.page-about .about-step:nth-child(4)::before {
  background: rgba(255, 138, 61, 0.18);
}

.page-about .about-step:hover,
.page-about .about-step:focus-within {
  border-color: var(--cyan);
  transform: translateY(-2px);
}

.page-about .about-step__num {
  position: relative;
  display: block;
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--orange);
}

.page-about .about-step__title {
  position: relative;
  margin: 8px 0 10px;
  font-size: 19px;
  line-height: 1.3;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--mist);
}

.page-about .about-step__text {
  position: relative;
  margin: 0;
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--cloud);
}

.page-about .about-method__media {
  margin: 24px 0 0;
  aspect-ratio: 3 / 2;
  border-radius: var(--radius);
  border: 1px solid var(--line-soft);
  background: linear-gradient(140deg, rgba(18, 55, 66, 0.9), rgba(26, 23, 56, 0.85));
}

/* 团队标签页 */
.page-about .about-tabs {
  margin-top: 26px;
}

.page-about .about-tablist {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line-soft);
}

.page-about .about-tab {
  padding: 9px 16px;
  border: 1px solid var(--line-soft);
  border-radius: 999px;
  background: transparent;
  color: var(--cloud);
  font-family: var(--font-sans);
  font-size: 13.5px;
  line-height: 1.2;
  cursor: pointer;
  transition: color 180ms var(--ease), border-color 180ms var(--ease), background 180ms var(--ease);
}

.page-about .about-tab:hover {
  color: var(--mist);
  border-color: var(--cyan);
}

.page-about .about-tab[aria-selected="true"] {
  color: var(--ink);
  background: var(--cyan);
  border-color: var(--cyan);
  font-weight: 700;
}

.page-about .about-tab:focus-visible {
  outline: 2px solid var(--orange);
  outline-offset: 2px;
}

.page-about .about-panel {
  padding: 22px;
  margin-top: 18px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: var(--about-panel-bg);
}

.page-about .about-panel__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
  gap: 12px;
  margin-bottom: 18px;
}

.page-about .about-role {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 14px 16px;
  border-radius: calc(var(--radius) - 4px);
  border: 1px solid rgba(30, 90, 99, 0.4);
  background: rgba(6, 19, 33, 0.55);
}

.page-about .about-role__num {
  font-size: 26px;
  line-height: 1.05;
  color: var(--orange);
  letter-spacing: 0.01em;
}

.page-about .about-role__label {
  font-size: 12.5px;
  color: var(--cloud);
}

.page-about .about-panel__text {
  margin: 0;
  max-width: 66ch;
  font-size: 15px;
  line-height: 1.78;
  color: var(--mist);
  opacity: 0.9;
}

/* 时间轴 */
.page-about .about-timeline {
  position: relative;
  margin: 28px 0 0;
  padding: 0 0 0 26px;
  list-style: none;
  border-left: 1px solid var(--line-soft);
}

.page-about .about-node {
  position: relative;
  padding-bottom: 14px;
}

.page-about .about-node::before {
  content: "";
  position: absolute;
  left: -31px;
  top: 12px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--ink);
  border: 2px solid var(--cyan);
}

.page-about .about-node--now::before {
  background: var(--orange);
  border-color: var(--orange);
  box-shadow: 0 0 0 4px rgba(255, 138, 61, 0.16);
}

.page-about .about-node details {
  border: 1px solid transparent;
  border-radius: var(--radius);
  transition: border-color 180ms var(--ease), background 180ms var(--ease);
}

.page-about .about-node details[open] {
  border-color: var(--line-soft);
  background: rgba(7, 42, 46, 0.55);
}

.page-about .about-node summary {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px;
  padding: 10px 14px;
  cursor: pointer;
  list-style: none;
  border-radius: var(--radius);
}

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

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

.page-about .about-node details[open] summary::after {
  content: "–";
}

.page-about .about-node summary:focus-visible {
  outline: 2px solid var(--orange);
  outline-offset: 2px;
}

.page-about .about-node__year {
  font-size: 14px;
  letter-spacing: 0.06em;
  color: var(--cyan);
}

.page-about .about-node--now .about-node__year {
  color: var(--orange);
}

.page-about .about-node__title {
  font-size: 15.5px;
  font-weight: 700;
  color: var(--mist);
}

.page-about .about-node__body {
  padding: 0 16px 14px;
}

.page-about .about-node__body p {
  margin: 0;
  max-width: 62ch;
  font-size: 14.5px;
  line-height: 1.76;
  color: var(--cloud);
}

/* 协作图例 */
.page-about .about-legend {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-legend__item {
  display: grid;
  grid-template-columns: 62px minmax(0, 1fr);
  align-items: start;
  gap: 14px;
  padding: 16px 18px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: rgba(7, 42, 46, 0.55);
}

.page-about .about-legend__item--accent {
  border-color: rgba(255, 138, 61, 0.55);
  background: linear-gradient(120deg, rgba(92, 32, 56, 0.5), rgba(6, 19, 33, 0.6));
}

.page-about .about-legend__key {
  font-size: 22px;
  line-height: 1.1;
  color: var(--cyan);
  letter-spacing: 0.01em;
}

.page-about .about-legend__item--accent .about-legend__key {
  color: var(--orange);
}

.page-about .about-legend__body {
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--cloud);
}

.page-about .about-legend__body strong {
  display: block;
  margin-bottom: 3px;
  font-size: 15px;
  color: var(--mist);
}

.page-about .about-partners__media {
  margin: 24px 0 0;
  aspect-ratio: 12 / 7;
  border-radius: var(--radius);
  border: 1px solid var(--line-soft);
  background: linear-gradient(150deg, rgba(26, 23, 56, 0.85), rgba(18, 55, 66, 0.85));
}

/* 云上视角 */
.page-about .about-vista {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 34px);
  margin-top: 22px;
}

.page-about .about-vista__list {
  display: grid;
  gap: 12px;
  margin: 0;
  padding: 20px;
  list-style: none;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: linear-gradient(160deg, rgba(26, 23, 56, 0.8), rgba(7, 42, 46, 0.7));
}

.page-about .about-vista__list li {
  display: grid;
  grid-template-columns: 14px minmax(0, 1fr);
  gap: 10px;
  align-items: start;
  font-size: 14px;
  line-height: 1.7;
  color: var(--cloud);
}

.page-about .about-vista__list strong {
  display: block;
  margin-bottom: 2px;
  font-size: 14.5px;
  color: var(--mist);
}

.page-about .about-vista__dot {
  width: 9px;
  height: 9px;
  margin-top: 7px;
  border-radius: 50%;
  display: inline-block;
}

.page-about .about-vista__dot--cyan {
  background: var(--cyan);
}

.page-about .about-vista__dot--mist {
  background: var(--mist);
}

.page-about .about-vista__dot--orange {
  background: var(--orange);
}

/* 下一步 */
.page-about .about-next {
  margin-top: clamp(30px, 4.4vw, 52px);
  padding: clamp(22px, 3.4vw, 34px);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background:
    radial-gradient(520px 220px at 90% 0%, rgba(53, 242, 208, 0.14), transparent 70%),
    linear-gradient(150deg, rgba(26, 23, 56, 0.9), rgba(6, 19, 33, 0.92));
}

.page-about .about-next__title {
  margin: 0 0 20px;
  font-size: clamp(22px, 2.8vw, 30px);
  line-height: 1.2;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--mist);
}

.page-about .about-next__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-about .about-next__card {
  display: grid;
  gap: 6px;
  padding: 18px;
  border: 1px solid var(--line-soft);
  border-radius: calc(var(--radius) - 2px);
  background: rgba(6, 19, 33, 0.55);
  text-decoration: none;
  transition: border-color 180ms var(--ease), transform 180ms var(--ease), background 180ms var(--ease);
}

.page-about .about-next__card:hover,
.page-about .about-next__card:focus-visible {
  border-color: var(--cyan);
  background: rgba(7, 42, 46, 0.8);
  transform: translateY(-2px);
}

.page-about .about-next__num {
  font-size: 11.5px;
  letter-spacing: 0.16em;
  color: var(--orange);
}

.page-about .about-next__name {
  font-size: 17px;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--mist);
}

.page-about .about-next__desc {
  font-size: 13.5px;
  line-height: 1.68;
  color: var(--cloud);
}

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

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

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

@media (min-width: 900px) {
  .page-about .about-hero__frame {
    grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
    align-items: center;
    padding: clamp(28px, 3.4vw, 46px);
  }

  .page-about .about-vista {
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 0.7fr);
    align-items: start;
  }
}

@media (min-width: 980px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-toc-w) minmax(0, 1fr);
    gap: clamp(28px, 4vw, 56px);
    align-items: start;
  }

  .page-about .about-toc {
    position: sticky;
    top: calc(var(--bar-h) + 20px);
    padding: 18px 16px;
  }

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

  .page-about .about-toc__link {
    border: 0;
    border-left: 2px solid transparent;
    border-radius: 0 8px 8px 0;
    padding: 8px 10px 8px 12px;
    white-space: normal;
    font-size: 13.5px;
  }

  .page-about .about-toc__link:hover,
  .page-about .about-toc__link:focus-visible {
    border-left-color: var(--cyan);
    background: rgba(53, 242, 208, 0.08);
  }

  .page-about .about-sec:first-child {
    padding-top: 6px;
  }

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

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

@media (prefers-reduced-motion: reduce) {
  .page-about .about-step,
  .page-about .about-next__card,
  .page-about .about-toc__link {
    transition: none;
  }

  .page-about .about-step:hover,
  .page-about .about-next__card:hover {
    transform: none;
  }
}
<<<END>>>