.page-about {
  background: var(--ink);
  color: var(--ice);
  font-family: var(--font-body);
}

.page-about img {
  max-width: 100%;
  height: auto;
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  padding: 26px 0 54px;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(120% 90% at 82% -10%, rgba(34, 245, 200, 0.1) 0%, transparent 58%),
    linear-gradient(180deg, var(--ink) 0%, var(--forest) 100%);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(var(--line-soft) 1px, transparent 1px),
    linear-gradient(90deg, var(--line-soft) 1px, transparent 1px);
  background-size: 56px 56px;
  -webkit-mask-image: radial-gradient(90% 72% at 62% 0%, #000 0%, transparent 74%);
  mask-image: radial-gradient(90% 72% at 62% 0%, #000 0%, transparent 74%);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 12px;
  pointer-events: none;
  background-image: repeating-linear-gradient(90deg, rgba(34, 245, 200, 0.26) 0 1px, transparent 1px 40px);
}

.page-about .about-hero .shell {
  position: relative;
  z-index: 1;
}

.page-about .about-hero__eyebrow {
  margin: 20px 0 0;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--cyan);
  text-transform: uppercase;
}

.page-about .about-hero__title {
  max-width: 16em;
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(32px, 7vw, 60px);
  line-height: 1.06;
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .about-hero__title em {
  font-style: normal;
  color: var(--cyan);
}

.page-about .about-hero__lede {
  max-width: 720px;
  margin: 20px 0 0;
  font-size: 16px;
  line-height: 1.78;
  color: var(--ice);
  opacity: 0.9;
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: 34px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .stat {
  padding: 16px 18px;
  background: var(--moss);
}

.page-about .stat__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: 0.01em;
  color: var(--cyan);
}

.page-about .stat__label {
  display: block;
  margin-top: 8px;
  font-size: 13px;
  color: var(--ice);
  opacity: 0.78;
}

/* ---------- 主体骨架 ---------- */

.page-about .about-body {
  padding: 44px 0 64px;
}

.page-about .about-body__grid {
  gap: 32px 44px;
  align-items: start;
}

.page-about .about-nav {
  position: sticky;
  top: 88px;
}

.page-about .about-nav__list {
  list-style: none;
  margin: 14px 0 0;
  padding: 0;
}

.page-about .about-nav__list li + li {
  margin-top: 2px;
}

.page-about .about-nav__list a {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 7px 10px;
  font-size: 13.5px;
  line-height: 1.5;
  color: var(--idx);
  text-decoration: none;
  border-left: 2px solid transparent;
  transition: color 0.18s var(--ease), background 0.18s var(--ease), border-color 0.18s var(--ease);
}

.page-about .about-nav__list a:hover {
  color: var(--ice);
  border-left-color: var(--cyan);
  background: rgba(34, 245, 200, 0.06);
}

.page-about .about-nav__num {
  font-size: 12px;
  color: var(--cyan);
  opacity: 0.75;
}

/* ---------- 章节通用 ---------- */

.page-about .about-sec {
  padding: 40px 0 46px;
  border-top: 1px solid var(--line);
  scroll-margin-top: 110px;
}

.page-about .about-sec:first-child {
  padding-top: 0;
  border-top: 0;
}

.page-about .about-sec__idx {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--cyan);
}

.page-about .about-sec__title {
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(23px, 3.6vw, 35px);
  line-height: 1.2;
  letter-spacing: -0.015em;
  color: var(--paper);
}

.page-about .about-sec__lede {
  max-width: 720px;
  margin: 14px 0 0;
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--ice);
  opacity: 0.86;
}

.page-about .about-sec__head--after {
  margin-top: 30px;
}

/* ---------- 四件事 ---------- */

.page-about .works {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: 28px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .work {
  padding: 22px 20px 24px;
  background: var(--forest);
  transition: background 0.2s var(--ease);
}

.page-about .work:hover {
  background: var(--moss);
}

.page-about .work__no {
  display: block;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.18em;
  color: var(--cyan);
  opacity: 0.85;
}

.page-about .work h3 {
  margin: 10px 0 10px;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .work p {
  margin: 0 0 15px;
  font-size: 14.5px;
  line-height: 1.72;
  color: var(--ice);
  opacity: 0.85;
}

.page-about .work__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .work__meta li {
  padding: 3px 8px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.04em;
  color: var(--cyan);
  border: 1px solid rgba(34, 245, 200, 0.28);
  border-radius: 2px;
}

/* ---------- 档案流程（分段切换） ---------- */

.page-about .dossier,
.page-about .team {
  position: relative;
  margin-top: 28px;
}

.page-about .dossier__radio,
.page-about .team__radio {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: 0;
  opacity: 0;
  pointer-events: none;
}

.page-about .dossier__tabs,
.page-about .team__tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--line);
}

.page-about .dossier__tab,
.page-about .team__tab {
  padding: 9px 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--idx);
  background: transparent;
  border: 1px solid var(--line);
  cursor: pointer;
  -webkit-user-select: none;
  user-select: none;
  transition: color 0.18s var(--ease), background 0.18s var(--ease), border-color 0.18s var(--ease);
}

.page-about .dossier__tab:hover,
.page-about .team__tab:hover {
  color: var(--ice);
  border-color: rgba(207, 230, 223, 0.34);
}

.page-about #ds-1:checked ~ .dossier__tabs label[for="ds-1"],
.page-about #ds-2:checked ~ .dossier__tabs label[for="ds-2"],
.page-about #ds-3:checked ~ .dossier__tabs label[for="ds-3"],
.page-about #ds-4:checked ~ .dossier__tabs label[for="ds-4"],
.page-about #tm-1:checked ~ .team__tabs label[for="tm-1"],
.page-about #tm-2:checked ~ .team__tabs label[for="tm-2"],
.page-about #tm-3:checked ~ .team__tabs label[for="tm-3"] {
  color: var(--ink);
  background: var(--cyan);
  border-color: var(--cyan);
}

.page-about .dossier__stage {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
  padding-top: 24px;
}

.page-about .dossier__panel,
.page-about .team__panel {
  display: none;
}

.page-about #ds-1:checked ~ .dossier__stage .dossier__panel[data-step="1"],
.page-about #ds-2:checked ~ .dossier__stage .dossier__panel[data-step="2"],
.page-about #ds-3:checked ~ .dossier__stage .dossier__panel[data-step="3"],
.page-about #ds-4:checked ~ .dossier__stage .dossier__panel[data-step="4"],
.page-about #tm-1:checked ~ .team__panels .team__panel[data-group="1"],
.page-about #tm-2:checked ~ .team__panels .team__panel[data-group="2"],
.page-about #tm-3:checked ~ .team__panels .team__panel[data-group="3"] {
  display: block;
}

.page-about .dossier__panel h3,
.page-about .team__panel h3 {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-size: 21px;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .dossier__panel p,
.page-about .team__panel p {
  margin: 0 0 16px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ice);
  opacity: 0.88;
}

.page-about .dossier__panel ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .dossier__panel li {
  position: relative;
  margin-bottom: 9px;
  padding-left: 18px;
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--ice);
  opacity: 0.84;
}

.page-about .dossier__panel li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 8px;
  height: 1px;
  background: var(--cyan);
}

.page-about .team__panels {
  padding-top: 22px;
}

.page-about .team__panel {
  max-width: 720px;
}

/* ---------- 图片块 ---------- */

.page-about .about-fig {
  position: relative;
  margin: 0;
}

.page-about .about-fig img {
  display: block;
  width: 100%;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  border: 1px solid var(--line);
  filter: saturate(0.94) contrast(1.04);
}

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

.page-about .about-fig--square img {
  aspect-ratio: 1 / 1;
}

.page-about .about-fig__cap {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.04em;
  color: var(--idx);
}

.page-about .timeline__fig {
  max-width: 420px;
  margin: 34px 0 0;
}

/* ---------- 时间线 ---------- */

.page-about .timeline {
  position: relative;
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 15px;
  top: 16px;
  bottom: 16px;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan) 0%, rgba(34, 245, 200, 0.14) 62%, transparent 100%);
}

.page-about .timeline__item {
  position: relative;
  padding-left: 46px;
}

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 17px;
  width: 9px;
  height: 9px;
  box-sizing: content-box;
  border-radius: 50%;
  border: 2px solid var(--cyan);
  background: var(--ink);
}

.page-about .timeline__item[data-now="true"]::before {
  border-color: var(--orange);
  background: var(--orange);
  box-shadow: 0 0 0 4px rgba(255, 106, 43, 0.18);
}

.page-about .tl__sum {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 10px 0;
  cursor: pointer;
  list-style: none;
  color: inherit;
}

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

.page-about .tl__sum::marker {
  content: "";
}

.page-about .tl__sum::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--idx);
}

.page-about .tl[open] .tl__sum::after {
  content: "–";
  color: var(--cyan);
}

.page-about .tl__year {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.06em;
  color: var(--cyan);
}

.page-about .tl__name {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  color: var(--paper);
  transition: color 0.18s var(--ease);
}

.page-about .tl__sum:hover .tl__name {
  color: var(--cyan);
}

.page-about .tl__body {
  max-width: 660px;
  padding: 4px 0 18px;
}

.page-about .tl__body p {
  margin: 0;
  font-size: 14.8px;
  line-height: 1.8;
  color: var(--ice);
  opacity: 0.86;
}

/* ---------- 团队 ---------- */

.page-about .team__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-bottom: 26px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .team__stat {
  padding: 18px;
  background: var(--forest);
}

.page-about .team__stat--lead {
  grid-column: 1 / -1;
  background: var(--moss);
}

.page-about .team__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 34px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: 0.01em;
  color: var(--cyan);
}

.page-about .team__stat--lead .team__num {
  font-size: 48px;
  color: var(--paper);
}

.page-about .team__lb {
  display: block;
  margin-top: 9px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--ice);
  opacity: 0.8;
}

/* ---------- 合作来源 ---------- */

.page-about .sources {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  margin-top: 26px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .source {
  padding: 24px 20px;
  background: var(--forest);
}

.page-about .source h3 {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .source__num {
  display: inline-block;
  margin-right: 6px;
  padding: 2px 8px;
  font-size: 14px;
  color: var(--ink);
  background: var(--orange);
  border-radius: 2px;
}

.page-about .source p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--ice);
  opacity: 0.86;
}

.page-about .sources__note {
  max-width: 720px;
  margin: 20px 0 0;
  padding-left: 16px;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--ice);
  opacity: 0.82;
  border-left: 2px solid var(--cyan);
}

/* ---------- 长期价值 ---------- */

.page-about .reasons {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.page-about .reason {
  padding: 22px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .reason__no {
  display: block;
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--cyan);
}

.page-about .reason h3 {
  margin: 10px 0 10px;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  color: var(--paper);
}

.page-about .reason p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--ice);
  opacity: 0.85;
}

/* ---------- 结尾行动区 ---------- */

.page-about .about-outro {
  position: relative;
  padding: 46px 0 64px;
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, var(--forest) 0%, var(--ink) 100%);
}

.page-about .about-outro::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--cyan) 0%, transparent 68%);
}

.page-about .about-outro__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(23px, 3.4vw, 33px);
  line-height: 1.22;
  letter-spacing: -0.015em;
  color: var(--paper);
}

.page-about .about-outro__lede {
  max-width: 660px;
  margin: 14px 0 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--ice);
  opacity: 0.86;
}

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

/* ---------- 响应式 ---------- */

@media (min-width: 720px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

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

@media (min-width: 900px) {
  .page-about .dossier__stage {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
    gap: 40px;
    align-items: start;
  }
}

@media (min-width: 1024px) {
  .page-about .about-hero {
    padding: 34px 0 66px;
  }

  .page-about .about-body {
    padding: 52px 0 76px;
  }

  .page-about .about-sec {
    padding: 46px 0 54px;
  }

  .page-about .team__stats {
    grid-template-columns: 1.4fr 1fr 1fr;
  }

  .page-about .team__stat--lead {
    grid-column: auto;
  }

  .page-about .reasons {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    border-bottom: 1px solid var(--line);
  }

  .page-about .reason {
    padding: 26px 24px 10px;
    border-bottom: 0;
    border-right: 1px solid var(--line);
  }

  .page-about .reason:first-child {
    padding-left: 0;
  }

  .page-about .reason:last-child {
    padding-right: 0;
    border-right: 0;
  }
}

@media (max-width: 1023px) {
  .page-about .about-body__grid {
    gap: 26px;
  }

  .page-about .about-nav {
    position: static;
  }

  .page-about .about-nav__list {
    display: flex;
    flex-wrap: nowrap;
    gap: 4px;
    min-width: 0;
    overflow-x: auto;
    padding-bottom: 6px;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: thin;
  }

  .page-about .about-nav__list li {
    flex: 0 0 auto;
  }

  .page-about .about-nav__list li + li {
    margin-top: 0;
  }

  .page-about .about-nav__list a {
    white-space: nowrap;
    padding: 7px 12px;
    border-left: 0;
    border-bottom: 2px solid transparent;
    background: rgba(18, 52, 45, 0.55);
  }

  .page-about .about-nav__list a:hover {
    border-left-color: transparent;
    border-bottom-color: var(--cyan);
  }
}

@media (max-width: 560px) {
  .page-about .about-hero__stats {
    grid-template-columns: minmax(0, 1fr);
  }

  .page-about .dossier__tab,
  .page-about .team__tab {
    flex: 1 1 100%;
    text-align: center;
  }

  .page-about .timeline__item {
    padding-left: 38px;
  }

  .page-about .tl__sum {
    flex-wrap: wrap;
    gap: 6px 12px;
  }

  .page-about .about-outro__actions .btn {
    flex: 1 1 100%;
    text-align: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-nav__list a,
  .page-about .dossier__tab,
  .page-about .team__tab,
  .page-about .work,
  .page-about .tl__name {
    transition: none;
  }
}