.page-about {
  --about-idx: 168px;
  --about-gap: clamp(24px, 4vw, 56px);
  max-width: var(--maxw);
  margin-inline: auto;
  padding: 0 var(--gutter) clamp(64px, 9vw, 104px);
  color: var(--mist);
}

.page-about .about-crumbs {
  padding-top: clamp(16px, 3vw, 28px);
  font-size: 13px;
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  padding-block: clamp(24px, 4vw, 48px) clamp(32px, 6vw, 72px);
  border-bottom: 1px solid var(--ink-700);
}

.page-about .about-hero__title {
  margin: 12px 0 0;
  font-family: var(--sans);
  font-weight: 700;
  font-stretch: 87.5%;
  font-size: clamp(1.85rem, 5.2vw, 3.4rem);
  line-height: 1.1;
  letter-spacing: -0.01em;
  max-width: 18em;
  color: var(--mist);
}

.page-about .about-hero__lead {
  margin: 20px 0 0;
  max-width: 38em;
  font-size: 16.5px;
  line-height: 1.78;
  color: var(--dim-dark);
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px 16px;
  margin: 32px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-hero__stats li {
  border-top: 1px solid var(--ink-700);
  padding-top: 12px;
  min-width: 0;
}

.page-about .about-hero__num {
  display: block;
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  font-size: clamp(1.5rem, 3.6vw, 2.1rem);
  line-height: 1.05;
  color: var(--amber);
}

.page-about .about-hero__cap {
  display: block;
  margin-top: 6px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--dim-dark);
}

/* ---------- 主体布局 ---------- */

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

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

/* ---------- 章节索引 ---------- */

.page-about .about-index {
  order: -1;
  padding: 20px 0 12px;
  border-bottom: 1px solid var(--ink-700);
  min-width: 0;
}

.page-about .about-index__title {
  margin: 0 0 10px;
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.1em;
  color: var(--dim-dark);
  text-transform: uppercase;
}

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

.page-about .about-index__list a {
  display: flex;
  gap: 8px;
  align-items: baseline;
  white-space: nowrap;
  padding: 7px 12px;
  border: 1px solid var(--ink-700);
  border-radius: 2px;
  color: var(--dim-dark);
  text-decoration: none;
  font-size: 13px;
  line-height: 1.3;
  transition: border-color 180ms var(--ease), color 180ms var(--ease);
}

.page-about .about-index__list a:hover,
.page-about .about-index__list a:focus-visible {
  border-color: var(--amber);
  color: var(--mist);
}

.page-about .about-index__n {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  font-size: 11px;
  letter-spacing: 0.04em;
  color: var(--amber);
}

/* ---------- 章节通用 ---------- */

.page-about .about-chapter {
  padding-block: clamp(48px, 9vw, 96px);
  border-top: 1px solid var(--ink-700);
  scroll-margin-top: 72px;
  min-width: 0;
}

.page-about .about-flow > .about-chapter:first-child {
  border-top: 0;
  padding-top: clamp(32px, 5vw, 48px);
}

.page-about .about-chapter__year {
  margin: 0 0 6px;
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  font-size: clamp(2.6rem, 11vw, 5.4rem);
  line-height: 0.86;
  letter-spacing: -0.02em;
  color: transparent;
  -webkit-text-stroke: 1.5px var(--ink-700);
}

.page-about .about-chapter__title {
  margin: 0 0 clamp(18px, 3vw, 28px);
  font-family: var(--sans);
  font-weight: 700;
  font-stretch: 87.5%;
  font-size: clamp(1.4rem, 3.4vw, 2.1rem);
  line-height: 1.16;
  letter-spacing: -0.01em;
  color: var(--mist);
  max-width: 26em;
}

.page-about .about-chapter__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 40px);
}

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

.page-about .about-chapter__prose p {
  max-width: 62ch;
  margin: 0 0 1.05em;
  font-size: 16.5px;
  line-height: 1.78;
  color: var(--mist);
  opacity: 0.88;
}

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

.page-about .about-chapter__prose a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(47, 224, 200, 0.4);
}

.page-about .about-chapter__prose a:hover,
.page-about .about-chapter__prose a:focus-visible {
  border-bottom-color: var(--cyan);
}

/* ---------- 图片 ---------- */

.page-about .about-figure {
  margin: 0;
  min-width: 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border-radius: 3px;
  border: 1px solid var(--ink-700);
  filter: saturate(0.92) contrast(1.04);
}

.page-about .about-figure--wide img {
  aspect-ratio: 16 / 9;
}

/* ---------- 覆盖 ---------- */

.page-about .about-coverage {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3.5vw, 32px);
}

.page-about .about-coverage__stats {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 1px;
  background: var(--ink-700);
  border: 1px solid var(--ink-700);
}

.page-about .about-coverage__stats li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 14px;
  align-items: baseline;
  padding: 16px 16px;
  background: var(--ink-800);
  min-width: 0;
}

.page-about .about-coverage__stats .num {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  font-size: clamp(1.5rem, 4vw, 2rem);
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-coverage__stats li > span:last-child {
  font-size: 14px;
  line-height: 1.65;
  color: var(--dim-dark);
}

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

.page-about .about-map {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  grid-auto-rows: clamp(18px, 4.6vw, 28px);
  grid-auto-flow: dense;
  gap: 6px;
  margin: 0 0 14px;
  padding: 0;
  list-style: none;
}

.page-about .about-map li {
  border-radius: 62% 38% 55% 45% / 40% 55% 45% 60%;
  background: var(--ink-700);
  opacity: 0.9;
}

.page-about .about-map li:nth-child(1) {
  grid-column: span 3;
  grid-row: span 2;
  background: var(--amber);
  opacity: 1;
}

.page-about .about-map li:nth-child(2) {
  grid-column: span 2;
  grid-row: span 2;
  background: var(--ink-700);
}

.page-about .about-map li:nth-child(3) { grid-column: span 1; grid-row: span 1; }
.page-about .about-map li:nth-child(4) { grid-column: span 2; grid-row: span 1; }
.page-about .about-map li:nth-child(5) { grid-column: span 1; grid-row: span 2; }
.page-about .about-map li:nth-child(6) { grid-column: span 2; grid-row: span 1; }
.page-about .about-map li:nth-child(7) { grid-column: span 3; grid-row: span 1; }
.page-about .about-map li:nth-child(8) { grid-column: span 2; grid-row: span 1; }
.page-about .about-map li:nth-child(9) { grid-column: span 1; grid-row: span 1; }
.page-about .about-map li:nth-child(10) { grid-column: span 3; grid-row: span 1; }
.page-about .about-map li:nth-child(11) { grid-column: span 2; grid-row: span 1; }

.page-about .about-coverage__note {
  margin: 0;
  max-width: 46ch;
  font-size: 14px;
  line-height: 1.7;
  color: var(--dim-dark);
}

.page-about .about-coverage ~ .about-figure,
.page-about .about-coverage + .about-figure {
  margin-top: clamp(24px, 4vw, 36px);
}

/* ---------- 团队旁注 ---------- */

.page-about .about-aside {
  margin: 0;
  padding: 0 0 0 16px;
  border-left: 2px solid var(--cyan);
  min-width: 0;
}

.page-about .about-aside__k {
  margin: 0 0 8px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--cyan);
  text-transform: uppercase;
}

.page-about .about-aside p:last-child {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--dim-dark);
}

/* ---------- 确认流程 ---------- */

.page-about .about-steps {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 10px;
}

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

.page-about .about-step details {
  background: var(--ink-800);
  border: 1px solid var(--ink-700);
  border-radius: 3px;
}

.page-about .about-step:last-child details {
  border-left: 3px solid var(--clay);
}

.page-about .about-step summary {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 15px 18px;
  cursor: pointer;
  list-style: none;
  font-family: var(--sans);
  font-weight: 700;
  font-size: 16px;
  line-height: 1.4;
  color: var(--mist);
}

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

.page-about .about-step summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--mono);
  font-weight: 500;
  color: var(--dim-dark);
}

.page-about .about-step details[open] summary::after {
  content: "−";
  color: var(--amber);
}

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

.page-about .about-step__n {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.06em;
  color: var(--amber);
}

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

.page-about .about-step__body {
  padding: 0 18px 18px;
  border-top: 1px solid var(--ink-700);
  margin-top: 0;
}

.page-about .about-step__body p {
  max-width: 62ch;
  margin: 14px 0 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--dim-dark);
}

/* ---------- 坚持的几件事 ---------- */

.page-about .about-principles {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 22px;
}

.page-about .about-principles li {
  padding-top: 16px;
  border-top: 2px solid var(--ink-700);
  min-width: 0;
}

.page-about .about-principles li:nth-child(1) {
  border-top-color: var(--amber);
}

.page-about .about-principles h3 {
  margin: 0 0 8px;
  font-family: var(--sans);
  font-weight: 700;
  font-size: 1.02rem;
  line-height: 1.4;
  color: var(--mist);
}

.page-about .about-principles p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--dim-dark);
}

.page-about .about-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(26px, 4vw, 36px);
}

/* ---------- 平板与桌面 ---------- */

@media (min-width: 700px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

  .page-about .about-principles {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 24px;
  }
}

@media (min-width: 900px) {
  .page-about .about-layout {
    grid-template-columns: var(--about-idx) minmax(0, 1fr);
    gap: var(--about-gap);
    align-items: start;
  }

  .page-about .about-index {
    position: sticky;
    top: 24px;
    order: 0;
    padding: 40px 16px 0 0;
    border-bottom: 0;
    border-right: 1px solid var(--ink-700);
  }

  .page-about .about-index__list {
    flex-direction: column;
    gap: 2px;
    overflow-x: visible;
    padding-bottom: 0;
  }

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

  .page-about .about-index__list a:hover,
  .page-about .about-index__list a:focus-visible {
    border-left-color: var(--amber);
    color: var(--mist);
  }

  .page-about .about-coverage {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    align-items: start;
  }

  .page-about .about-coverage ~ .about-figure {
    margin-top: clamp(28px, 4vw, 44px);
  }
}

@media (min-width: 1000px) {
  .page-about .about-chapter__grid--media {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: start;
  }

  .page-about .about-figure--offset {
    margin-top: 48px;
  }

  .page-about .about-chapter__grid--split {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: start;
  }

  .page-about .about-chapter__grid--reverse {
    grid-template-columns: minmax(0, 4fr) minmax(0, 6fr);
    align-items: start;
  }

  .page-about .about-chapter__grid--reverse .about-chapter__prose {
    padding-top: 8px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index__list a {
    transition: none;
  }
}
<<<END>>>