.page-about {
  --about-hair: rgba(46, 58, 107, 0.9);
  --about-soft-cyan: rgba(43, 232, 210, 0.14);
  --about-soft-orange: rgba(255, 122, 46, 0.14);
  --about-soft-violet: rgba(108, 92, 231, 0.3);

  background: var(--indigo-850);
  color: var(--slate-100);
  overflow-x: hidden;
}

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

/* ---------- 首屏：主题声明 + 导读 ---------- */
.about-masthead {
  position: relative;
  padding-block: clamp(30px, 4.6vw, 56px) clamp(48px, 7vw, 92px);
  border-bottom: 1px solid var(--line-600);
  background:
    radial-gradient(115% 125% at 88% -12%, var(--about-soft-violet), transparent 58%),
    radial-gradient(90% 95% at -14% 112%, rgba(43, 232, 210, 0.12), transparent 60%),
    var(--indigo-850);
  overflow: hidden;
}

.about-masthead::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(233, 238, 250, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(233, 238, 250, 0.045) 1px, transparent 1px);
  background-size: 24px 24px;
  -webkit-mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.92), transparent 76%);
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.92), transparent 76%);
}

.about-masthead .container {
  position: relative;
  z-index: 1;
}

.about-masthead__grid {
  display: grid;
  gap: clamp(30px, 5vw, 52px);
  margin-top: clamp(26px, 4vw, 46px);
}

.about-masthead__title {
  margin: 14px 0 0;
  max-width: 15ch;
  font-size: clamp(34px, 6.4vw, 74px);
  font-weight: 800;
  line-height: 1.05;
  letter-spacing: -0.015em;
  color: var(--slate-100);
}

.about-lead {
  margin: 22px 0 0;
  max-width: 44ch;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
  color: var(--slate-350);
}

.about-masthead__label {
  margin: 0 0 12px;
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--slate-350);
}

.about-toc {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 2px;
}

.about-toc a {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 9px 12px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  color: var(--slate-100);
  font-size: 14px;
  text-decoration: none;
  transition: border-color 180ms var(--ease), background 180ms var(--ease);
}

.about-toc a:hover,
.about-toc a:focus-visible {
  border-color: rgba(43, 232, 210, 0.5);
  background: rgba(43, 232, 210, 0.07);
}

.about-toc .mono {
  font-size: 11px;
  letter-spacing: 0.05em;
  color: var(--cyan-400);
}

/* ---------- 通用章节节奏 ---------- */
.about-section {
  padding-block: clamp(56px, 9vw, 118px);
}

.about-section + .about-section {
  border-top: 1px solid var(--line-600);
}

/* ---------- 时间轴 ---------- */
.about-timeline__visual {
  margin: 0 0 clamp(30px, 5vw, 54px);
}

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

.about-timeline::before {
  content: "";
  position: absolute;
  top: 14px;
  bottom: 14px;
  left: 9px;
  width: 1px;
  background: linear-gradient(180deg, transparent, rgba(43, 232, 210, 0.65) 8%, var(--line-600) 58%, transparent);
}

.about-timeline__item {
  position: relative;
  padding: 10px 0 10px 38px;
}

.about-timeline__item::before {
  content: "";
  position: absolute;
  top: 26px;
  left: 9px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--cyan-400);
  box-shadow: 0 0 0 4px var(--about-soft-cyan);
  transform: translateX(-50%);
  z-index: 2;
}

.about-node {
  border: 1px solid var(--line-600);
  border-radius: var(--radius-lg);
  background: linear-gradient(155deg, rgba(27, 39, 80, 0.96), rgba(16, 24, 56, 0.72));
  transition: border-color 180ms var(--ease), transform 180ms var(--ease);
}

.about-node:hover {
  border-color: rgba(43, 232, 210, 0.55);
  transform: translateY(-2px);
}

.about-node__head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: 10px 14px;
  padding: 16px 18px;
  list-style: none;
  cursor: pointer;
}

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

.about-node__head:focus-visible {
  outline: 2px solid var(--cyan-400);
  outline-offset: -3px;
  border-radius: var(--radius-lg);
}

.about-node__year {
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--cyan-400);
}

.about-node__title {
  font-size: clamp(15px, 2vw, 17px);
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--slate-100);
}

.about-node__mark {
  position: relative;
  width: 18px;
  height: 18px;
  flex: none;
}

.about-node__mark::before,
.about-node__mark::after {
  content: "";
  position: absolute;
  inset: 0;
  margin: auto;
  background: var(--cyan-400);
  transition: transform 220ms var(--ease), opacity 220ms var(--ease);
}

.about-node__mark::before {
  width: 14px;
  height: 2px;
}

.about-node__mark::after {
  width: 2px;
  height: 14px;
}

.about-node[open] .about-node__mark::after {
  transform: scaleY(0);
  opacity: 0;
}

.about-node__body {
  padding: 0 18px 18px;
  border-top: 1px solid rgba(46, 58, 107, 0.6);
  margin-top: 0;
  padding-top: 14px;
}

.about-node__body p {
  margin: 0;
  max-width: 46ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--slate-350);
}

/* ---------- 每天在做的事 ---------- */
.about-daily {
  display: grid;
  gap: 22px;
}

.about-daily__card {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 24px 22px 26px;
  border-top: 3px solid rgba(43, 232, 210, 0.5);
}

.about-daily__card:nth-child(2) {
  border-top-color: rgba(255, 122, 46, 0.62);
}

.about-daily__card:nth-child(3) {
  border-top-color: rgba(108, 92, 231, 0.72);
}

.about-daily__cue {
  margin: 0;
  font-size: 13px;
  letter-spacing: 0.02em;
  color: var(--cyan-400);
}

.about-daily__card:nth-child(2) .about-daily__cue {
  color: var(--orange-500);
}

.about-daily__card:nth-child(3) .about-daily__cue {
  color: #A99BFF;
}

/* ---------- 数据带 ---------- */
.about-metrics__bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: clamp(22px, 3vw, 34px);
}

.about-metrics__grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  border: 1px solid var(--line-600);
  border-radius: var(--radius-lg);
  background: var(--line-600);
  overflow: hidden;
}

.about-metric {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 20px 18px;
  background: var(--indigo-850);
  transition: background 180ms var(--ease);
}

.about-metric:hover {
  background: var(--indigo-700);
}

.about-metric__value {
  font-size: clamp(24px, 3.6vw, 36px);
  font-weight: 500;
  line-height: 1;
  color: var(--cyan-400);
}

.about-metric__label {
  font-size: 13px;
  line-height: 1.6;
  color: var(--slate-350);
}

/* ---------- 团队 ---------- */
.about-team__visual {
  margin: 0 0 clamp(30px, 4.5vw, 48px);
}

.about-roles {
  margin: 0;
  padding: 0;
  list-style: none;
}

.about-role {
  display: grid;
  gap: 6px;
  padding: 20px 0;
  border-top: 1px solid var(--line-600);
  transition: border-color 180ms var(--ease);
}

.about-role:last-child {
  border-bottom: 1px solid var(--line-600);
}

.about-role:hover {
  border-top-color: rgba(43, 232, 210, 0.6);
}

.about-role__name {
  font-size: 16px;
  font-weight: 700;
  color: var(--slate-100);
}

.about-role__count {
  font-size: 13px;
  color: var(--orange-500);
}

.about-role__desc {
  margin: 0;
  max-width: 64ch;
  font-size: 15px;
  line-height: 1.75;
  color: var(--slate-350);
}

/* ---------- 覆盖范围 ---------- */
.about-coverage__grid {
  display: grid;
  gap: clamp(30px, 5vw, 54px);
}

.about-coverage__title {
  margin: 12px 0 0;
  font-size: clamp(25px, 3.8vw, 40px);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.012em;
  color: var(--slate-100);
}

.about-coverage__body .prose {
  margin-top: 20px;
}

.about-coverage__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
}

.about-coverage__tags li {
  padding: 7px 14px;
  border: 1px solid var(--line-600);
  border-radius: var(--radius-pill);
  font-size: 13px;
  color: var(--slate-350);
}

.about-coverage__visual {
  margin: 0;
  aspect-ratio: 4 / 3;
}

/* ---------- 合作与认可 ---------- */
.about-partners__grid {
  display: grid;
  gap: 20px;
}

.about-partner {
  position: relative;
  padding: 24px 22px;
  border: 1px solid var(--line-600);
  border-radius: var(--radius-lg);
  background: linear-gradient(160deg, rgba(27, 39, 80, 0.7), rgba(16, 24, 56, 0.4));
  transition: border-color 180ms var(--ease), transform 180ms var(--ease);
}

.about-partner:hover {
  border-color: rgba(43, 232, 210, 0.5);
  transform: translateY(-2px);
}

.about-partner__index {
  display: block;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--cyan-400);
}

.about-partner__title {
  margin: 12px 0 8px;
  font-size: 18px;
  font-weight: 700;
  color: var(--slate-100);
}

.about-partner__text {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--slate-350);
}

.about-honors {
  margin-top: clamp(34px, 5vw, 56px);
  padding-top: clamp(24px, 3.5vw, 36px);
  border-top: 1px dashed var(--line-600);
}

.about-honors__title {
  margin: 0 0 18px;
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 0.12em;
  color: var(--slate-350);
}

.about-honors__list {
  display: grid;
  gap: 14px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.about-honor {
  display: flex;
  align-items: center;
  gap: 16px;
}

.about-honor__badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 64px;
  padding: 5px 12px;
  border: 1px solid rgba(43, 232, 210, 0.4);
  border-radius: var(--radius-pill);
  font-size: 13px;
  color: var(--cyan-400);
}

.about-honor__text {
  font-size: 15px;
  color: var(--slate-100);
}

/* ---------- 下一步 ---------- */
.about-next__panel {
  display: grid;
  gap: clamp(28px, 4vw, 44px);
  padding: clamp(24px, 4.2vw, 52px);
  border: 1px solid var(--line-600);
  border-radius: var(--radius-lg);
  background:
    radial-gradient(95% 130% at 100% 0%, var(--about-soft-orange), transparent 60%),
    radial-gradient(85% 130% at 0% 100%, rgba(43, 232, 210, 0.1), transparent 62%),
    var(--indigo-700);
}

.about-next__title {
  margin: 12px 0 0;
  font-size: clamp(24px, 3.4vw, 36px);
  font-weight: 800;
  line-height: 1.22;
  letter-spacing: -0.012em;
  color: var(--slate-100);
}

.about-next__text {
  margin: 16px 0 0;
  max-width: 42ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--slate-350);
}

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

.about-next__list {
  display: grid;
  gap: 20px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.about-next__list li {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 4px 14px;
}

.about-next__list .mono {
  grid-row: span 2;
  padding-top: 3px;
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--cyan-400);
}

.about-next__list strong {
  font-size: 16px;
  color: var(--slate-100);
}

.about-next__list p {
  margin: 0;
  font-size: 14px;
  line-height: 1.72;
  color: var(--slate-350);
}

.about-next__links {
  margin-top: clamp(34px, 5vw, 56px);
}

.about-next__links-lead {
  margin: 0;
  font-size: 14px;
  color: var(--slate-350);
}

.about-linkrow {
  display: grid;
  gap: 10px;
  margin: 18px 0 0;
  padding: 0;
  list-style: none;
}

.about-linkrow a {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 13px 16px;
  border: 1px solid var(--line-600);
  border-radius: var(--radius-md);
  color: var(--slate-100);
  font-size: 14px;
  text-decoration: none;
  transition: border-color 180ms var(--ease), background 180ms var(--ease);
}

.about-linkrow a::before {
  content: "";
  width: 6px;
  height: 6px;
  flex: none;
  border-radius: 50%;
  background: var(--cyan-400);
}

.about-linkrow a:hover,
.about-linkrow a:focus-visible {
  border-color: rgba(43, 232, 210, 0.55);
  background: rgba(43, 232, 210, 0.06);
}

/* ---------- 中屏 ---------- */
@media (min-width: 760px) {
  .about-daily {
    gap: 24px;
  }

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

  .about-role {
    grid-template-columns: 180px 88px minmax(0, 1fr);
    align-items: baseline;
    gap: 0 20px;
  }
}

/* ---------- 大屏 ---------- */
@media (min-width: 940px) {
  .about-masthead__grid {
    grid-template-columns: minmax(0, 8fr) minmax(0, 3fr);
    gap: clamp(32px, 6vw, 84px);
    align-items: end;
  }

  .about-timeline::before {
    left: 50%;
    top: 12px;
    bottom: 12px;
  }

  .about-timeline__item {
    width: 50%;
    padding: 16px 0;
  }

  .about-timeline__item::before {
    left: auto;
    right: -5px;
    top: 32px;
    transform: none;
  }

  .about-timeline__item:nth-child(odd) {
    padding-right: 46px;
  }

  .about-timeline__item:nth-child(even) {
    margin-left: 50%;
    padding-left: 46px;
  }

  .about-timeline__item:nth-child(even)::before {
    right: auto;
    left: -5px;
  }

  .about-daily {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 26px;
    align-items: start;
  }

  .about-daily__card:nth-child(2) {
    margin-top: 30px;
  }

  .about-daily__card:nth-child(3) {
    margin-top: 60px;
  }

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

  .about-coverage__grid {
    grid-template-columns: minmax(0, 8fr) minmax(0, 4fr);
    gap: clamp(36px, 6vw, 82px);
    align-items: start;
  }

  .about-coverage__visual {
    aspect-ratio: 3 / 4;
  }

  .about-next__panel {
    grid-template-columns: minmax(0, 5fr) minmax(0, 6fr);
    gap: clamp(32px, 5vw, 76px);
    align-items: start;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-node,
  .page-about .about-partner,
  .page-about .about-metric,
  .page-about .about-toc a,
  .page-about .about-linkrow a {
    transition: none;
  }

  .page-about .about-node:hover,
  .page-about .about-partner:hover {
    transform: none;
  }
}