.page-about {
  --about-pad: clamp(56px, 9vw, 132px);
  --about-ink-soft: rgba(10, 18, 25, .78);
  background: var(--abyss);
  color: var(--cream);
  overflow-x: clip;
}

/* 面包屑 */
.page-about .about-crumbs {
  padding-top: clamp(20px, 4vw, 34px);
}
.page-about .about-crumbs ol {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--stone);
}
.page-about .about-crumbs a {
  color: var(--stone);
  text-decoration: none;
  transition: color var(--dur) var(--ease);
}
.page-about .about-crumbs a:hover,
.page-about .about-crumbs a:focus-visible {
  color: var(--pulse);
}
.page-about .about-crumbs li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--steel);
}

/* 首屏 */
.page-about .about-hero {
  padding-block: clamp(36px, 6vw, 84px) clamp(52px, 8vw, 112px);
}
.page-about .about-hero-grid {
  display: grid;
  gap: clamp(36px, 5vw, 68px);
}
.page-about .about-kicker {
  margin: 0 0 18px;
  color: var(--pulse);
}
.page-about .about-h1 {
  margin: 0 0 clamp(20px, 3vw, 30px);
  font-family: var(--font-display);
  font-weight: 900;
  letter-spacing: -.02em;
}
.page-about .about-h1-sub {
  display: block;
  margin-bottom: 12px;
  font-size: clamp(12px, 1.6vw, 14px);
  font-weight: 500;
  letter-spacing: .38em;
  color: var(--mist);
}
.page-about .about-h1-main {
  display: block;
  font-size: clamp(44px, 10vw, 92px);
  line-height: .96;
}
.page-about .about-lead {
  max-width: 30em;
  margin: 0;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.9;
  color: rgba(242, 237, 227, .86);
}
.page-about .about-hero-actions {
  margin: clamp(24px, 4vw, 36px) 0 0;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .about-hero-side {
  display: block;
}
.page-about .about-annotation {
  display: none;
}
.page-about .about-figures {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
}
.page-about .about-figures li {
  background: var(--harbor);
  padding: 18px 16px 20px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.page-about .about-fig-num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(26px, 4.4vw, 40px);
  line-height: 1;
  color: var(--lemon);
  letter-spacing: -.02em;
}
.page-about .about-fig-unit {
  font-size: .45em;
  margin-left: 2px;
  color: var(--mist);
}
.page-about .about-fig-label {
  font-size: 12px;
  line-height: 1.5;
  color: var(--stone);
}

/* 章节索引条 */
.page-about .about-toc {
  position: sticky;
  top: var(--quickbar-h);
  z-index: 6;
  background: rgba(6, 19, 32, .94);
  border-block: 1px solid var(--line-soft);
}
.page-about .about-toc-inner {
  display: flex;
  align-items: center;
  gap: 18px;
  padding-block: 12px;
  overflow-x: auto;
  scrollbar-width: none;
}
.page-about .about-toc-inner::-webkit-scrollbar {
  display: none;
}
.page-about .about-toc-title {
  flex: none;
  color: var(--steel);
}
.page-about .about-toc-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 22px;
  white-space: nowrap;
}
.page-about .about-toc-list a {
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  font-size: 13px;
  color: var(--stone);
  text-decoration: none;
  transition: color var(--dur) var(--ease);
}
.page-about .about-toc-list a:hover,
.page-about .about-toc-list a:focus-visible {
  color: var(--cream);
}
.page-about .toc-num {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--pulse);
  letter-spacing: .06em;
}

/* 章节通用 */
.page-about .about-sec {
  position: relative;
  padding-block: var(--about-pad);
  overflow: hidden;
}
.page-about .about-sec--cream {
  background: var(--cream);
  color: var(--ink);
}
.page-about .about-sec--harbor {
  background: var(--harbor);
}
.page-about .about-sec-wrap {
  position: relative;
  z-index: 1;
}
.page-about .about-index {
  position: absolute;
  top: -.16em;
  left: -.06em;
  z-index: 0;
  font-family: var(--font-mono);
  font-size: clamp(90px, 21vw, 190px);
  font-weight: 700;
  line-height: .8;
  letter-spacing: -.06em;
  color: var(--pulse);
  opacity: .14;
  pointer-events: none;
  user-select: none;
}
.page-about .about-index--ink {
  color: var(--ink);
  opacity: .1;
}
.page-about .about-sec-head {
  position: relative;
  z-index: 1;
  margin-bottom: clamp(26px, 4vw, 46px);
}
.page-about .about-sec-head h2 {
  margin: 0;
  max-width: 20em;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(25px, 4.4vw, 46px);
  line-height: 1.12;
  letter-spacing: -.015em;
}
.page-about .about-sec-sub {
  margin: 14px 0 0;
  max-width: 32em;
  font-size: 14px;
  line-height: 1.8;
  color: var(--stone);
}
.page-about .about-sec--cream .label-en {
  color: var(--terracotta);
}
.page-about .about-sec--cream .about-sec-sub {
  color: var(--about-ink-soft);
}

/* 起点 */
.page-about .about-two-col {
  position: relative;
  z-index: 1;
  display: grid;
  gap: clamp(28px, 4vw, 56px);
}
.page-about .about-copy p {
  margin: 0 0 1.15em;
  max-width: 34em;
  font-size: 15.5px;
  line-height: 1.9;
}
.page-about .about-sec--cream .about-copy p {
  color: var(--about-ink-soft);
}
.page-about .about-copy p:last-child {
  margin-bottom: 0;
}
.page-about .about-quote {
  padding-left: 16px;
  border-left: 2px solid var(--terracotta);
  font-weight: 600;
  color: var(--ink) !important;
}
.page-about .about-figure {
  margin: 0;
  border: 1px solid var(--line-soft);
  overflow: hidden;
}
.page-about .about-sec--cream .about-figure {
  border-color: rgba(10, 18, 25, .22);
}
.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}
.page-about .about-sec--cream .media-frame__caption {
  color: rgba(10, 18, 25, .6);
}

/* 时间轴 */
.page-about .about-timeline-sec {
  isolation: isolate;
}
.page-about .about-banner {
  position: absolute;
  inset: 0;
  z-index: 0;
  overflow: hidden;
}
.page-about .about-banner img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: .26;
}
.page-about .about-banner::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, var(--abyss) 0%, rgba(6, 19, 32, .45) 46%, var(--abyss) 100%);
}
.page-about .about-timeline {
  position: relative;
  z-index: 1;
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.page-about .about-phase-card {
  border: 1px solid var(--line-soft);
  background: rgba(13, 42, 66, .62);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}
.page-about .about-phase-card:hover {
  transform: translateY(-2px);
  border-color: var(--steel);
}
.page-about .about-phase-card[open] {
  border-color: var(--pulse);
}
.page-about .about-phase-summary {
  list-style: none;
  cursor: pointer;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 12px;
  padding: 16px 18px;
}
.page-about .about-phase-summary::-webkit-details-marker {
  display: none;
}
.page-about .about-phase-summary:focus-visible {
  outline: 2px solid var(--pulse);
  outline-offset: 2px;
}
.page-about .about-phase-year {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 18px;
  color: var(--lemon);
  letter-spacing: .02em;
}
.page-about .about-phase-name {
  font-size: 15.5px;
  font-weight: 600;
  color: var(--cream);
}
.page-about .about-phase-caret {
  width: 0;
  height: 0;
  border-left: 5px solid transparent;
  border-right: 5px solid transparent;
  border-top: 6px solid var(--stone);
  transition: transform var(--dur) var(--ease), border-top-color var(--dur) var(--ease);
}
.page-about .about-phase-card[open] .about-phase-caret {
  transform: rotate(180deg);
  border-top-color: var(--pulse);
}
.page-about .about-phase-body {
  padding: 0 18px 18px;
}
.page-about .about-phase-body p {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: var(--stone);
}

/* 团队 */
.page-about .about-team {
  position: relative;
  z-index: 1;
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
  grid-template-columns: minmax(0, 1fr);
}
.page-about .about-team-card {
  border: 1px solid var(--line-soft);
  background: rgba(6, 19, 32, .42);
  padding: 20px 18px 22px;
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.page-about .about-team-card:hover {
  transform: translateY(-4px);
  border-color: var(--steel);
}
.page-about .about-team-id {
  display: block;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .16em;
  color: var(--pulse);
  opacity: .3;
  transition: opacity var(--dur) var(--ease);
}
.page-about .about-team-card:hover .about-team-id {
  opacity: 1;
}
.page-about .about-team-num {
  margin: 10px 0 2px;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(40px, 6vw, 58px);
  line-height: 1;
  color: var(--lemon);
  letter-spacing: -.03em;
}
.page-about .about-team-card h3 {
  margin: 0 0 8px;
  font-size: 17px;
  font-weight: 700;
  letter-spacing: .02em;
}
.page-about .about-team-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: var(--stone);
}

/* 资料校对 */
.page-about .about-check {
  position: relative;
  z-index: 1;
  display: grid;
  gap: clamp(28px, 4vw, 52px);
}
.page-about .about-steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 22px;
}
.page-about .about-steps li {
  padding-left: 16px;
  border-left: 1px solid rgba(10, 18, 25, .22);
}
.page-about .about-step-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--terracotta);
  margin-bottom: 6px;
}
.page-about .about-steps h3 {
  margin: 0 0 6px;
  font-size: 17px;
  font-weight: 700;
  color: var(--ink);
}
.page-about .about-steps p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--about-ink-soft);
}
.page-about .about-flow {
  margin: 0;
  border: 1px solid rgba(10, 18, 25, .18);
  padding: clamp(16px, 3vw, 26px);
}
.page-about .about-flow-svg {
  display: block;
  width: 100%;
  height: auto;
}
.page-about .about-flow-lines path {
  fill: none;
  stroke: var(--steel);
  stroke-width: 1.5;
}
.page-about .about-flow-lines path:last-child {
  stroke: var(--pulse);
}
.page-about .about-flow-nodes circle {
  fill: var(--cream);
  stroke: var(--steel);
  stroke-width: 1.5;
}
.page-about .about-flow-nodes circle:nth-of-type(4) {
  fill: var(--pulse);
  stroke: none;
}
.page-about .about-flow-nodes rect {
  fill: none;
  stroke: var(--terracotta);
  stroke-width: 1.5;
}
.page-about .about-flow-labels text {
  font-family: var(--font-body);
  font-size: 16px;
  font-weight: 600;
  fill: var(--ink);
}
.page-about .about-flow-labels text + text {
  font-size: 12px;
  font-weight: 400;
  fill: rgba(10, 18, 25, .6);
}

/* 服务范围 */
.page-about .about-reach {
  position: relative;
  z-index: 1;
  display: grid;
  gap: clamp(28px, 4vw, 56px);
}
.page-about .about-reach-copy p {
  margin: 0 0 1.1em;
  max-width: 32em;
  font-size: 15.5px;
  line-height: 1.9;
  color: rgba(242, 237, 227, .84);
}
.page-about .about-reach-link {
  margin-top: 22px;
}
.page-about .about-link {
  display: inline-block;
  font-size: 14.5px;
  font-weight: 600;
  color: var(--pulse);
  text-decoration: none;
  border-bottom: 1px solid rgba(44, 232, 200, .38);
  padding-bottom: 3px;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.page-about .about-link:hover,
.page-about .about-link:focus-visible {
  color: var(--lemon);
  border-color: var(--lemon);
}
.page-about .about-reach-stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
}
.page-about .about-reach-stats li {
  background: var(--abyss);
  padding: 16px 18px;
  display: flex;
  align-items: baseline;
  gap: 14px;
}
.page-about .about-stat-num {
  flex: none;
  min-width: 2.6em;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(24px, 3.4vw, 32px);
  line-height: 1;
  color: var(--lemon);
}
.page-about .about-stat-text {
  font-size: 13px;
  line-height: 1.6;
  color: var(--stone);
}

/* 三件事 */
.page-about .about-creed {
  padding-block: var(--about-pad);
  background: linear-gradient(160deg, var(--harbor) 0%, var(--abyss) 62%);
  border-top: 1px solid var(--line-soft);
}
.page-about .about-creed-label {
  margin: 0 0 14px;
  color: var(--pulse);
}
.page-about .about-creed-title {
  margin: 0 0 clamp(28px, 4vw, 46px);
  max-width: 18em;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(24px, 4.2vw, 44px);
  line-height: 1.14;
  letter-spacing: -.015em;
}
.page-about .about-creed-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 26px;
}
.page-about .about-creed-list li {
  padding-top: 16px;
  border-top: 1px solid var(--steel);
}
.page-about .about-creed-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--terracotta);
  margin-bottom: 10px;
}
.page-about .about-creed-list h3 {
  margin: 0 0 8px;
  font-size: 19px;
  font-weight: 700;
  letter-spacing: .01em;
}
.page-about .about-creed-list p {
  margin: 0;
  max-width: 24em;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--stone);
}

/* 继续阅读 */
.page-about .about-next {
  padding-block: clamp(48px, 6vw, 84px) clamp(56px, 7vw, 96px);
  background: var(--abyss);
  border-top: 1px solid var(--line-soft);
}
.page-about .about-next-title {
  margin: 0 0 24px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(20px, 2.6vw, 26px);
  letter-spacing: .01em;
}
.page-about .about-next-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
}
.page-about .about-next-list a {
  display: flex;
  flex-direction: column;
  gap: 7px;
  padding: 20px 18px 22px;
  background: var(--abyss);
  text-decoration: none;
  color: var(--cream);
  transition: background var(--dur) var(--ease);
}
.page-about .about-next-list a:hover,
.page-about .about-next-list a:focus-visible {
  background: var(--harbor);
}
.page-about .about-next-name {
  font-size: 16px;
  font-weight: 700;
}
.page-about .about-next-desc {
  font-size: 13px;
  line-height: 1.7;
  color: var(--stone);
}
.page-about .about-next-list .label-en {
  color: var(--pulse);
}

/* 响应式 */
@media (min-width: 640px) {
  .page-about .about-team {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-next-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .page-about .about-creed-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 22px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: start;
  }
  .page-about .about-hero-side {
    display: flex;
    gap: 22px;
    align-items: flex-start;
    justify-content: flex-end;
  }
  .page-about .about-annotation {
    display: block;
    margin: 0;
    padding-top: 8px;
    writing-mode: vertical-rl;
    font-size: 11px;
    letter-spacing: .3em;
    color: var(--stone);
    white-space: nowrap;
  }
  .page-about .about-figures {
    flex: 1 1 auto;
    max-width: 260px;
  }
  .page-about .about-two-col {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
    align-items: start;
  }
  .page-about .about-check {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: center;
  }
  .page-about .about-reach {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, .9fr);
    align-items: start;
  }
  .page-about .about-timeline {
    flex-direction: row;
    gap: 0;
    align-items: flex-start;
  }
  .page-about .about-phase {
    position: relative;
    flex: 1 1 0;
    padding: 36px 14px 0 0;
  }
  .page-about .about-phase::before {
    content: "";
    position: absolute;
    top: 8px;
    left: 0;
    right: 0;
    height: 1px;
    background: var(--line);
  }
  .page-about .about-phase:last-child::before {
    background: linear-gradient(90deg, var(--line), transparent);
  }
  .page-about .about-phase::after {
    content: "";
    position: absolute;
    top: 3px;
    left: 0;
    width: 11px;
    height: 11px;
    border-radius: 50%;
    background: var(--terracotta);
    transition: background var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
  }
  .page-about .about-phase:has(details[open])::after {
    background: var(--pulse);
    box-shadow: 0 0 0 4px rgba(44, 232, 200, .16);
  }
}

@media (min-width: 1024px) {
  .page-about .about-team {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 1100px) {
  .page-about .about-next-list {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about * {
    transition-duration: .01ms !important;
    animation-duration: .01ms !important;
  }
  .page-about .about-phase-card:hover,
  .page-about .about-team-card:hover {
    transform: none;
  }
}
<<<END>>>
</main>