.page-about {
  --ch-ink: var(--bright);
  --ch-muted: var(--muted);
  --ch-line: var(--line);
  --ch-line-soft: var(--line-soft);
  background: var(--night);
  color: var(--bright);
}

.page-about .about-hero {
  padding: clamp(96px, 14vh, 152px) 0 clamp(28px, 5vw, 48px);
}

.page-about .about-hero__frame {
  position: relative;
  margin-top: clamp(18px, 3vw, 32px);
  padding: clamp(20px, 3.4vw, 48px);
  display: grid;
  gap: clamp(24px, 4vw, 48px);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background:
    radial-gradient(120% 90% at 100% 0%, rgba(75, 255, 196, 0.08), transparent 58%),
    linear-gradient(180deg, var(--panel), rgba(11, 33, 24, 0.55));
  box-shadow: var(--shadow-soft);
}

.page-about .about-hero__frame::before,
.page-about .about-hero__frame::after {
  content: "";
  position: absolute;
  width: 22px;
  height: 22px;
  border: 1px solid var(--mint-line);
  pointer-events: none;
}

.page-about .about-hero__frame::before {
  top: -1px;
  left: -1px;
  border-right: 0;
  border-bottom: 0;
  border-top-left-radius: var(--radius);
}

.page-about .about-hero__frame::after {
  bottom: -1px;
  right: -1px;
  border-left: 0;
  border-top: 0;
  border-bottom-right-radius: var(--radius);
}

.page-about .about-hero__lead h1 {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(34px, 6.4vw, 68px);
  line-height: 1.06;
  letter-spacing: 0.01em;
  color: var(--bright);
}

.page-about .about-hero__text {
  margin: 18px 0 0;
  max-width: 46ch;
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.8;
  color: var(--ch-muted);
}

.page-about .about-hero__text + .about-hero__text {
  margin-top: 12px;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: clamp(22px, 3vw, 32px);
}

.page-about .about-hero__figure {
  margin: 0;
  align-self: start;
}

.page-about .media__frame {
  overflow: hidden;
  border: 1px solid var(--ch-line);
  border-radius: var(--radius-sm);
  background: var(--raised);
}

.page-about .media__frame img {
  display: block;
  width: 100%;
  height: 100%;
  max-width: 100%;
  object-fit: cover;
}

.page-about .about-hero__figure .media__caption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--muted);
}

/* 章节索引 */
.page-about .about-toc {
  padding: 0 0 clamp(36px, 6vw, 64px);
}

.page-about .about-toc__list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 6px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
}

.page-about .about-toc__item {
  flex: 0 0 auto;
}

.page-about .about-toc__link {
  display: grid;
  grid-template-columns: auto 1fr;
  align-items: center;
  gap: 8px;
  padding: 10px 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  color: var(--bright);
  text-decoration: none;
  background: rgba(18, 49, 39, 0.35);
  transition: border-color 140ms var(--ease), background-color 140ms var(--ease);
}

.page-about .about-toc__num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--mint);
}

.page-about .about-toc__label {
  font-size: 13px;
  letter-spacing: 0.04em;
  white-space: nowrap;
}

.page-about .about-toc__note {
  grid-column: 1 / -1;
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  font-size: 12px;
  line-height: 1.6;
  color: var(--muted);
  transition: max-height 160ms var(--ease), opacity 160ms var(--ease);
}

.page-about .about-toc__link:hover,
.page-about .about-toc__link:focus-visible {
  border-color: var(--mint-line);
  background: var(--raised);
}

.page-about .about-toc__link:hover .about-toc__note,
.page-about .about-toc__link:focus-visible .about-toc__note {
  max-height: 60px;
  opacity: 1;
  margin-top: 2px;
}

/* 章节通用 */
.page-about .about-chapter {
  padding: clamp(48px, 8vw, 96px) 0;
  border-top: 1px solid var(--line-soft);
  scroll-margin-top: 96px;
}

.page-about .about-chapter__grid {
  display: grid;
  gap: clamp(20px, 3vw, 40px);
}

.page-about .about-chapter__aside {
  display: grid;
  gap: 6px;
  align-content: start;
}

.page-about .about-chapter__num {
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(54px, 14vw, 104px);
  line-height: 0.86;
  letter-spacing: -0.02em;
  color: rgba(244, 247, 240, 0.16);
}

.page-about .about-chapter__title {
  margin: 0;
  font-family: var(--font-body);
  font-weight: 600;
  font-size: clamp(22px, 3.2vw, 32px);
  line-height: 1.36;
  letter-spacing: 0.005em;
  color: var(--ch-ink);
}

.page-about .about-chapter__body p {
  margin: 0 0 14px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ch-muted);
}

.page-about .about-lede {
  font-size: clamp(16px, 1.7vw, 19px) !important;
  line-height: 1.75 !important;
  color: var(--ch-ink) !important;
  padding-left: 14px;
  border-left: 2px solid var(--mint);
}

.page-about .about-chapter__body strong {
  color: var(--ch-ink);
}

/* 01 起点 */
.page-about .about-points {
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 1px;
  background: var(--ch-line);
  border: 1px solid var(--ch-line);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.page-about .about-points li {
  display: grid;
  grid-template-columns: 62px 1fr;
  gap: 12px;
  padding: 13px 16px;
  background: var(--panel);
  font-size: 14px;
  line-height: 1.7;
  color: var(--ch-muted);
}

.page-about .about-points__num {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--mint);
}

/* 02 三重主张（纸面） */
.page-about .about-chapter--paper {
  --ch-ink: var(--brown);
  --ch-muted: rgba(30, 20, 15, 0.74);
  --ch-line: rgba(30, 20, 15, 0.16);
  --ch-line-soft: rgba(30, 20, 15, 0.1);
  background: var(--cream);
  color: var(--brown);
  border-top-color: rgba(30, 20, 15, 0.14);
}

.page-about .about-chapter--paper .about-chapter__num {
  color: rgba(30, 20, 15, 0.16);
}

.page-about .about-chapter--paper .about-points li {
  background: var(--paper-hi);
}

.page-about .about-tenet {
  position: relative;
  padding: 18px 0 20px 22px;
  border-bottom: 1px solid var(--ch-line);
}

.page-about .about-tenet:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .about-tenet__mark {
  position: absolute;
  left: 0;
  top: 24px;
  width: 9px;
  height: 14px;
  border-radius: 2px;
}

.page-about .about-tenet__mark--mint {
  background: var(--mint);
}

.page-about .about-tenet__mark--yellow {
  background: var(--yellow);
}

.page-about .about-tenet__mark--red {
  background: var(--red);
}

.page-about .about-tenet h3 {
  margin: 0 0 8px;
  font-size: clamp(16px, 1.8vw, 18px);
  font-weight: 600;
  letter-spacing: 0.01em;
  color: var(--ch-ink);
}

.page-about .about-tenet p {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: var(--ch-muted);
}

/* 03 时间轴 */
.page-about .about-timeline {
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-timeline__item {
  position: relative;
  padding: 0 0 26px 26px;
  border-left: 1px solid var(--ch-line);
}

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

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: -5px;
  top: 7px;
  width: 9px;
  height: 9px;
  border-radius: 2px;
  background: var(--mint);
}

.page-about .about-timeline__item:nth-child(2)::before,
.page-about .about-timeline__item:nth-child(5)::before {
  background: var(--yellow);
}

.page-about .about-timeline__item:nth-child(3)::before,
.page-about .about-timeline__item:nth-child(6)::before {
  background: var(--red);
}

.page-about .about-timeline__year {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--muted);
}

.page-about .about-timeline__title {
  margin: 4px 0 6px;
  font-size: clamp(16px, 1.8vw, 19px);
  font-weight: 600;
  color: var(--ch-ink);
}

.page-about .about-timeline__item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--ch-muted);
}

.page-about .about-chapter__media {
  margin: clamp(24px, 4vw, 36px) 0 0;
}

.page-about .about-chapter__media .media__caption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--muted);
}

.page-about .about-chapter--paper .about-chapter__media .media__caption {
  color: rgba(30, 20, 15, 0.6);
}

/* 04 校对流程 */
.page-about .about-steps {
  display: grid;
  gap: 1px;
  margin: 22px 0 20px;
  background: var(--ch-line);
  border: 1px solid var(--ch-line);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.page-about .about-step {
  background: var(--paper-hi);
}

.page-about .about-step__summary {
  display: grid;
  grid-template-columns: 34px 1fr;
  align-items: center;
  gap: 10px;
  padding: 15px 16px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .about-step__summary:hover {
  background: rgba(30, 20, 15, 0.05);
}

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

.page-about .about-step__num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--brown);
  opacity: 0.55;
}

.page-about .about-step__name {
  font-size: 15px;
  font-weight: 600;
  color: var(--brown);
}

.page-about .about-step__hint {
  grid-column: 2 / -1;
  font-size: 12px;
  color: rgba(30, 20, 15, 0.6);
}

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

.page-about .about-step__body p {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: rgba(30, 20, 15, 0.74);
}

/* 05 规模 */
.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 22px 0;
  background: var(--ch-line);
  border: 1px solid var(--ch-line);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.page-about .about-stats__cell {
  display: grid;
  gap: 4px;
  padding: 16px 14px;
  background: var(--panel);
}

.page-about .about-stats__num {
  font-family: var(--font-mono);
  font-size: clamp(22px, 3.4vw, 30px);
  line-height: 1.1;
  color: var(--mint);
  letter-spacing: -0.01em;
}

.page-about .about-stats__label {
  font-size: 12px;
  line-height: 1.6;
  color: var(--muted);
}

.page-about .about-team {
  border-top: 1px solid var(--ch-line);
  padding-top: 18px;
}

.page-about .about-team h3 {
  margin: 0 0 12px;
  font-size: 15px;
  font-weight: 600;
  color: var(--ch-ink);
  letter-spacing: 0.02em;
}

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

.page-about .about-team__list li {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 10px 0;
  border-bottom: 1px solid var(--ch-line-soft);
  font-size: 14px;
  color: var(--ch-muted);
}

.page-about .about-team__list li:last-child {
  border-bottom: 0;
}

.page-about .about-team__count {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--ch-ink);
}

/* 06 合作 */
.page-about .about-partner-grid {
  display: grid;
  gap: 1px;
  margin-top: 22px;
  background: var(--ch-line);
  border: 1px solid var(--ch-line);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.page-about .about-partner {
  padding: 18px 16px;
  background: var(--paper-hi);
}

.page-about .about-partner h3 {
  margin: 0 0 8px;
  font-size: 15px;
  font-weight: 600;
  color: var(--brown);
}

.page-about .about-partner p {
  margin: 0 0 10px;
  font-size: 13.5px;
  line-height: 1.8;
  color: rgba(30, 20, 15, 0.74);
}

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

.page-about .about-inline-link {
  color: var(--brown);
  text-decoration: none;
  border-bottom: 1px solid var(--red);
  padding-bottom: 1px;
  font-size: 13.5px;
}

.page-about .about-inline-link:hover,
.page-about .about-inline-link:focus-visible {
  color: #8c2318;
  border-bottom-color: var(--brown);
}

.page-about .about-closing {
  margin-top: clamp(26px, 4vw, 40px);
  padding: 20px;
  border: 1px solid rgba(30, 20, 15, 0.2);
  border-radius: var(--radius-sm);
  background: rgba(247, 243, 231, 0.7);
  display: grid;
  gap: 16px;
  justify-items: start;
}

.page-about .about-closing p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: rgba(30, 20, 15, 0.8);
}

/* 焦点可见 */
.page-about a:focus-visible,
.page-about summary:focus-visible {
  outline: 2px solid var(--mint);
  outline-offset: 3px;
}

.page-about .about-chapter--paper a:focus-visible,
.page-about .about-chapter--paper summary:focus-visible {
  outline-color: var(--brown);
}

@media (min-width: 880px) {
  .page-about .about-hero__frame {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    align-items: start;
  }

  .page-about .about-toc__list {
    display: grid;
    grid-template-columns: repeat(6, minmax(0, 1fr));
    gap: 10px;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .about-toc__item {
    flex: initial;
  }

  .page-about .about-toc__link {
    border-radius: var(--radius-sm);
    grid-template-columns: auto 1fr;
    align-items: baseline;
  }

  .page-about .about-toc__label {
    white-space: normal;
  }

  .page-about .about-chapter__grid {
    grid-template-columns: minmax(0, 0.82fr) minmax(0, 1.55fr);
    gap: clamp(32px, 5vw, 80px);
    align-items: start;
  }

  .page-about .about-chapter__aside {
    position: sticky;
    top: 104px;
  }

  .page-about .about-chapter__num {
    font-size: clamp(72px, 9vw, 132px);
  }

  .page-about .about-points li {
    grid-template-columns: 74px 1fr;
  }

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

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

  .page-about .about-step__summary {
    grid-template-columns: 40px minmax(0, 1fr) auto;
    gap: 14px;
  }

  .page-about .about-step__hint {
    grid-column: auto;
    text-align: right;
  }

  .page-about .about-timeline {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: clamp(28px, 4vw, 48px);
  }
}

@media (min-width: 1180px) {
  .page-about .about-timeline {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-timeline__item:nth-child(3n) {
    padding-right: 0;
  }

  .page-about .about-closing {
    grid-template-columns: 1fr auto;
    align-items: center;
    justify-items: stretch;
    padding: 26px 28px;
  }
}

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