.page-about .about-hero {
  position: relative;
  padding: 112px 0 44px;
  background:
    radial-gradient(110% 80% at 92% 0%, rgba(255, 106, 26, .12), transparent 62%),
    var(--ink-900);
  overflow: hidden;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background: var(--hair);
}

.page-about .about-hero__grid {
  display: grid;
  gap: 32px;
  margin-top: 26px;
}

.page-about .about-hero__text h1 {
  margin: 14px 0 0;
  font-family: var(--font-head);
  font-size: clamp(34px, 8vw, 60px);
  font-weight: 600;
  line-height: 1.08;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .about-hero__lead {
  margin: 20px 0 0;
  max-width: 46em;
  font-size: 16px;
  line-height: 1.78;
  color: var(--muted-on-dark);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.page-about .about-stats {
  margin: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--hair);
  border: 1px solid var(--hair);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.page-about .about-stats .stat {
  display: flex;
  flex-direction: column-reverse;
  gap: 8px;
  padding: 20px 16px;
  background: var(--ink-800);
}

.page-about .about-stats dd {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 600;
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--paper);
}

.page-about .about-stats dt {
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--muted-on-dark);
}

/* 区块标题 */
.page-about .sec-head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 16px;
  align-items: start;
  margin-bottom: 30px;
}

.page-about .sec-idx {
  font-family: var(--font-mono);
  font-size: 34px;
  font-weight: 600;
  line-height: .95;
  letter-spacing: -.04em;
  color: transparent;
  -webkit-text-stroke: 1px var(--hair-strong);
}

.page-about .sec-head__body h2 {
  margin: 0;
  font-family: var(--font-head);
  font-size: clamp(24px, 4.6vw, 34px);
  font-weight: 600;
  line-height: 1.22;
  letter-spacing: -.01em;
  color: var(--text-on-dark);
}

.page-about .sec-head__body p {
  margin: 10px 0 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--muted-on-dark);
}

/* 01 我们在做的事 */
.page-about .doing-grid {
  display: grid;
  gap: 18px;
}

.page-about .doing-main {
  padding: 24px 22px;
  background: var(--ink-800);
  border: 1px solid var(--hair);
  border-radius: var(--radius-md);
}

.page-about .doing-main h3 {
  margin: 0 0 14px;
  font-family: var(--font-head);
  font-size: 19px;
  font-weight: 600;
  color: var(--paper);
}

.page-about .doing-main p {
  margin: 0 0 14px;
  font-size: 15.5px;
  line-height: 1.8;
  color: var(--muted-on-dark);
}

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

.page-about .doing-side {
  padding: 24px 22px;
  background: var(--orange-tint);
  border: 1px solid rgba(255, 106, 26, .34);
  border-radius: var(--radius-md);
}

.page-about .doing-side__label {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--orange);
}

.page-about .doing-side__big {
  margin: 14px 0 0;
  font-family: var(--font-mono);
  font-size: clamp(30px, 7vw, 40px);
  font-weight: 600;
  line-height: 1.05;
  letter-spacing: -.03em;
  color: var(--paper);
}

.page-about .doing-side__note {
  margin: 14px 0 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--muted-on-dark);
}

.page-about .doing-side__link {
  display: inline-block;
  margin-top: 18px;
  font-size: 14.5px;
  font-weight: 600;
  color: var(--orange);
  text-decoration: none;
  border-bottom: 1px solid rgba(255, 106, 26, .5);
  padding-bottom: 2px;
}

.page-about .doing-side__link:hover,
.page-about .doing-side__link:focus-visible {
  color: var(--paper);
  border-bottom-color: var(--paper);
}

/* 02 为什么用序号 */
.page-about .why-grid {
  display: grid;
  gap: 26px;
}

.page-about .why-text > p {
  margin: 0 0 16px;
  font-size: 15.5px;
  line-height: 1.82;
  color: var(--muted-on-dark);
}

.page-about .why-list {
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--hair);
}

.page-about .why-list li {
  display: grid;
  grid-template-columns: 52px minmax(0, 1fr);
  gap: 14px;
  padding: 14px 0;
  border-bottom: 1px solid var(--hair);
  font-size: 15px;
  line-height: 1.72;
  color: var(--text-on-dark);
}

.page-about .why-list__num {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--teal);
  padding-top: 3px;
}

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

/* 时间线 */
.page-about .tl-figure {
  margin: 0 0 26px;
}

.page-about .timeline {
  display: grid;
  gap: 14px;
}

.page-about .tl-entry {
  background: var(--ink-800);
  border: 1px solid var(--hair);
  border-radius: var(--radius-md);
  transition: border-color .22s var(--ease), background .22s var(--ease);
}

.page-about .tl-entry:hover {
  border-color: var(--hair-strong);
}

.page-about .tl-entry[open] {
  border-color: rgba(255, 106, 26, .42);
  background: var(--ink-700);
}

.page-about .tl-entry > summary {
  display: grid;
  grid-template-columns: 32px minmax(0, 1fr) 24px;
  grid-template-areas:
    "idx year toggle"
    "idx name toggle";
  gap: 4px 14px;
  align-items: center;
  padding: 18px 18px;
  cursor: pointer;
  list-style: none;
}

.page-about .tl-entry > summary::-webkit-details-marker {
  display: none;
}

.page-about .tl-idx {
  grid-area: idx;
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 600;
  color: var(--gray-300);
  align-self: center;
}

.page-about .tl-year {
  grid-area: year;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .1em;
  color: var(--orange);
}

.page-about .tl-name {
  grid-area: name;
  font-family: var(--font-head);
  font-size: 16.5px;
  font-weight: 500;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .tl-toggle {
  grid-area: toggle;
  display: grid;
  place-items: center;
  width: 24px;
  height: 24px;
  font-size: 14px;
  color: var(--muted-on-dark);
  border: 1px solid var(--hair-strong);
  border-radius: var(--pill);
  transition: transform .22s var(--ease), color .22s var(--ease), border-color .22s var(--ease);
}

.page-about .tl-entry[open] .tl-toggle {
  transform: rotate(45deg);
  color: var(--orange);
  border-color: rgba(255, 106, 26, .55);
}

.page-about .tl-body {
  padding: 0 18px 20px;
}

.page-about .tl-body p {
  margin: 0 0 12px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted-on-dark);
}

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

.page-about .tl-entry--current .tl-idx {
  color: var(--orange);
}

/* 04 团队分工 */
.page-about .team-band {
  display: grid;
  gap: 14px;
}

.page-about .team {
  position: relative;
  padding: 24px 22px 22px;
  background: var(--ink-800);
  border: 1px solid var(--hair);
  border-radius: var(--radius-md);
  transition: background .22s var(--ease), border-color .22s var(--ease);
}

.page-about .team:hover,
.page-about .team:focus-within {
  background: var(--ink-700);
  border-color: rgba(255, 106, 26, .42);
}

.page-about .team-num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: .14em;
  color: var(--gray-300);
}

.page-about .team h3 {
  margin: 10px 0 0;
  font-family: var(--font-head);
  font-size: 19px;
  font-weight: 600;
  color: var(--paper);
}

.page-about .team-desc {
  margin: 12px 0 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--muted-on-dark);
}

.page-about .team-kws {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 18px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .team-kws li {
  padding: 5px 11px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--gray-300);
  background: rgba(195, 206, 216, .08);
  border-radius: var(--pill);
  transition: color .22s var(--ease), background .22s var(--ease);
}

.page-about .team:hover .team-kws li {
  color: var(--orange);
  background: var(--orange-tint);
}

.page-about .team-figure {
  margin: 22px 0 0;
}

.page-about .team-foot {
  margin: 22px 0 0;
  padding: 16px 0 0;
  border-top: 1px solid var(--hair);
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--muted-on-dark);
}

/* 05 取舍标准 */
.page-about .criteria {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 0;
  border-top: 1px solid var(--hair);
}

.page-about .criterion {
  display: grid;
  grid-template-columns: 46px minmax(0, 1fr);
  gap: 6px 16px;
  padding: 22px 0;
  border-bottom: 1px solid var(--hair);
}

.page-about .criterion__num {
  grid-row: span 2;
  font-family: var(--font-mono);
  font-size: 20px;
  font-weight: 600;
  line-height: 1.2;
  color: var(--orange);
}

.page-about .criterion h3 {
  margin: 0;
  font-family: var(--font-head);
  font-size: 17.5px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--text-on-dark);
}

.page-about .criterion p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted-on-dark);
}

/* 06 收尾承诺 */
.page-about .about-closing {
  padding: 52px 0 64px;
  background: var(--gray-100);
  color: var(--ink-900);
}

.page-about .closing-grid {
  display: grid;
  gap: 28px;
}

.page-about .about-closing h2 {
  margin: 0 0 16px;
  font-family: var(--font-head);
  font-size: clamp(23px, 4.6vw, 32px);
  font-weight: 600;
  line-height: 1.24;
  letter-spacing: -.01em;
  color: var(--ink-900);
}

.page-about .about-closing p {
  margin: 0 0 14px;
  font-size: 15.5px;
  line-height: 1.8;
  color: #3C4E60;
}

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

.page-about .closing-card {
  padding: 22px 20px;
  background: var(--paper);
  border: 1px solid rgba(16, 38, 58, .1);
  border-radius: var(--radius-md);
}

.page-about .closing-card__label {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--orange-deep);
}

.page-about .closing-link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 13px 0;
  font-size: 15px;
  font-weight: 500;
  color: var(--ink-900);
  text-decoration: none;
  border-bottom: 1px solid rgba(16, 38, 58, .12);
  transition: color .2s var(--ease), padding-left .2s var(--ease);
}

.page-about .closing-link:last-child {
  border-bottom: 0;
}

.page-about .closing-link:hover,
.page-about .closing-link:focus-visible {
  color: var(--orange-deep);
  padding-left: 6px;
}

.page-about .closing-link--accent {
  color: var(--orange-deep);
  font-weight: 600;
}

/* 平板及以上 */
@media (min-width: 720px) {
  .page-about .about-hero {
    padding: 126px 0 56px;
  }

  .page-about .doing-grid {
    grid-template-columns: minmax(0, 1.45fr) minmax(0, 1fr);
    gap: 20px;
  }

  .page-about .doing-main,
  .page-about .doing-side {
    padding: 28px 26px;
  }

  .page-about .sec-head {
    gap: 22px;
  }

  .page-about .sec-idx {
    font-size: 46px;
  }

  .page-about .about-stats dd {
    font-size: 34px;
  }

  .page-about .criterion {
    grid-template-columns: 64px minmax(0, 1fr);
    gap: 8px 22px;
    padding: 26px 0;
  }

  .page-about .criterion__num {
    font-size: 24px;
  }
}

@media (min-width: 940px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: 52px;
    align-items: end;
  }

  .page-about .about-stats .stat {
    padding: 22px 18px;
  }

  .page-about .why-grid {
    grid-template-columns: minmax(0, 6fr) minmax(0, 5fr);
    gap: 44px;
    align-items: start;
  }

  .page-about .tl-entry > summary {
    grid-template-columns: 56px 92px minmax(0, 1fr) 26px;
    grid-template-areas: "idx year name toggle";
    gap: 18px;
    padding: 22px 26px;
  }

  .page-about .tl-idx {
    font-size: 17px;
  }

  .page-about .tl-name {
    font-size: 17.5px;
  }

  .page-about .tl-body {
    padding: 0 26px 22px 26px;
    max-width: 62em;
  }

  .page-about .team-band {
    grid-template-columns: 1.16fr 1fr .84fr;
    gap: 18px;
  }

  .page-about .team {
    padding: 28px 24px;
  }

  .page-about .team-figure {
    margin-top: 26px;
  }

  .page-about .closing-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    gap: 48px;
    align-items: start;
  }

  .page-about .about-closing {
    padding: 62px 0 78px;
  }
}
<<<END>>>