.page-about {
  --about-hairline: var(--ink-600);
  --about-line-num: var(--font-num);
}

.page-about .num {
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  letter-spacing: -0.02em;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: 28px 0 56px;
  background:
    linear-gradient(180deg, var(--ink-900) 0%, var(--ink-800) 62%, var(--ink-800) 100%);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    linear-gradient(112deg, transparent 0 58%, rgba(255, 74, 43, 0.1) 58% 74%, transparent 74%),
    repeating-linear-gradient(112deg, transparent 0 26px, rgba(255, 74, 43, 0.05) 26px 28px);
}

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

.page-about .about-hero__grid {
  display: grid;
  gap: 32px;
  margin: 24px 0 36px;
}

.page-about .about-hero h1 {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(30px, 7vw, 64px);
  line-height: 1.12;
  letter-spacing: -0.03em;
  max-width: 18ch;
}

.page-about .about-hero .lede {
  margin: 20px 0 0;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.8;
  color: var(--text-dim);
}

.page-about .about-keyfacts {
  margin: 0;
  border-top: 3px solid var(--accent);
}

.page-about .about-keyfacts__row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: baseline;
  gap: 12px;
  padding: 12px 0;
  border-bottom: 1px solid var(--about-hairline);
}

.page-about .about-keyfacts dt {
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--text-dim);
  line-height: 1.5;
}

.page-about .about-keyfacts dd {
  margin: 0;
  display: flex;
  align-items: baseline;
  gap: 3px;
  color: var(--text);
}

.page-about .about-keyfacts dd .num {
  font-size: clamp(24px, 5vw, 34px);
  color: var(--accent);
}

.page-about .about-keyfacts dd em {
  font-style: normal;
  font-size: 13px;
  color: var(--text-dim);
}

.page-about .about-hero__media {
  margin: 0;
}

/* ---------- 通用区块骨架 ---------- */
.page-about .about-section {
  position: relative;
  padding: 56px 0;
  border-top: 3px solid var(--about-hairline);
}

.page-about .about-section--band {
  background: linear-gradient(180deg, var(--ink-900) 0%, var(--ink-800) 100%);
}

.page-about .about-section__head {
  display: grid;
  gap: 14px;
  margin-bottom: 36px;
  max-width: 64ch;
}

.page-about .about-section__index {
  margin: 0;
  font-family: var(--font-num);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.18em;
  color: var(--accent);
}

.page-about .about-section__index::before {
  content: "";
  display: inline-block;
  width: 10px;
  height: 10px;
  margin-right: 10px;
  vertical-align: middle;
  background: var(--accent);
  clip-path: polygon(0 0, 100% 0, 100% 60%, 60% 100%, 0 100%);
}

.page-about .about-section__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(24px, 5.2vw, 40px);
  line-height: 1.2;
  letter-spacing: -0.02em;
  max-width: 20ch;
}

.page-about .about-section__lead {
  margin: 0;
  font-size: 16px;
  line-height: 1.78;
  color: var(--text-dim);
  max-width: 64ch;
}

/* ---------- 四条数据线 ---------- */
.page-about .about-lines {
  display: grid;
  gap: 0;
  border-top: 1px solid var(--about-hairline);
}

.page-about .about-line {
  position: relative;
  padding: 26px 0 26px 20px;
  border-bottom: 1px solid var(--about-hairline);
}

.page-about .about-line::before {
  content: "";
  position: absolute;
  left: 0;
  top: 30px;
  width: 6px;
  height: 26px;
  background: var(--accent);
  clip-path: polygon(0 0, 100% 0, 100% 68%, 0 100%);
}

.page-about .about-line--youth::before {
  background: var(--youth);
}

.page-about .about-line--transfer::before {
  background: var(--transfer);
}

.page-about .about-line__tag {
  margin: 0 0 8px;
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--text-dim);
}

.page-about .about-line--youth .about-line__tag {
  color: var(--youth);
}

.page-about .about-line--transfer .about-line__tag {
  color: var(--transfer);
}

.page-about .about-line__title {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-size: clamp(19px, 3.4vw, 24px);
  font-weight: 700;
  line-height: 1.3;
  letter-spacing: -0.01em;
}

.page-about .about-line p {
  margin: 0 0 12px;
  max-width: 58ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-dim);
}

.page-about .about-line__meta {
  margin: 0;
}

.page-about .about-line__meta a {
  display: inline-block;
  font-size: 14px;
  font-weight: 700;
  color: var(--accent);
  text-decoration: none;
  border-bottom: 2px solid var(--accent);
  padding-bottom: 2px;
}

.page-about .about-line__meta a:hover {
  color: var(--accent-soft);
  border-bottom-color: var(--accent-soft);
}

/* ---------- 沿革时间线 ---------- */
.page-about .about-timeline {
  display: grid;
  gap: 0;
  border-top: 3px solid var(--about-hairline);
}

.page-about .about-era {
  border-bottom: 1px solid var(--about-hairline);
}

.page-about .about-era__summary {
  display: grid;
  grid-template-columns: 58px minmax(0, 1fr) 18px;
  align-items: center;
  gap: 14px;
  padding: 20px 0;
  cursor: pointer;
  list-style: none;
}

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

.page-about .about-era__summary:hover .about-era__name {
  color: var(--accent-soft);
}

.page-about .about-era__year {
  font-family: var(--font-num);
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--accent);
}

.page-about .about-era__name {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--text);
  transition: color 180ms var(--ease);
}

.page-about .about-era__toggle {
  position: relative;
  justify-self: end;
  width: 16px;
  height: 16px;
}

.page-about .about-era__toggle::before,
.page-about .about-era__toggle::after {
  content: "";
  position: absolute;
  background: var(--accent);
  transition: transform 200ms var(--ease);
}

.page-about .about-era__toggle::before {
  left: 0;
  top: 7px;
  width: 16px;
  height: 2px;
}

.page-about .about-era__toggle::after {
  left: 7px;
  top: 0;
  width: 2px;
  height: 16px;
}

.page-about .about-era[open] .about-era__toggle::after {
  transform: scaleY(0);
}

.page-about .about-era__body {
  padding: 0 0 24px;
  max-width: 66ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-dim);
}

.page-about .about-era__body p {
  margin: 0;
}

/* ---------- 团队分工矩阵 ---------- */
.page-about .about-team__filter {
  margin-bottom: 28px;
}

.page-about .about-team__matrix {
  display: grid;
  gap: 1px;
  background: var(--about-hairline);
  border: 1px solid var(--about-hairline);
}

.page-about .about-team__cell {
  display: grid;
  align-content: start;
  gap: 10px;
  padding: 24px 20px 28px;
  background: var(--ink-700);
}

.page-about .about-team__cell.is-filtered {
  display: none;
}

.page-about .about-team__cell--youth {
  background: linear-gradient(180deg, var(--ink-700) 0%, rgba(43, 227, 168, 0.09) 100%);
  box-shadow: inset 3px 0 0 0 var(--youth);
}

.page-about .about-team__cell--transfer {
  background: linear-gradient(180deg, var(--ink-700) 0%, rgba(255, 194, 74, 0.09) 100%);
  box-shadow: inset 3px 0 0 0 var(--transfer);
}

.page-about .about-team__count {
  display: flex;
  align-items: baseline;
  gap: 4px;
  margin: 0;
  color: var(--text);
}

.page-about .about-team__count .num {
  font-size: clamp(38px, 8vw, 48px);
  line-height: 1;
  color: var(--text);
}

.page-about .about-team__cell--youth .about-team__count .num {
  color: var(--youth);
}

.page-about .about-team__cell--transfer .about-team__count .num {
  color: var(--transfer);
}

.page-about .about-team__count em {
  font-style: normal;
  font-size: 13px;
  color: var(--text-dim);
}

.page-about .about-team__cell h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  line-height: 1.35;
}

.page-about .about-team__cell p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text-dim);
}

/* ---------- 赛后复核 ---------- */
.page-about .about-review {
  display: grid;
  gap: 32px;
}

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

.page-about .about-steps > li {
  position: relative;
  padding: 0 0 28px 20px;
  border-left: 2px solid var(--about-hairline);
}

.page-about .about-steps > li:last-child {
  padding-bottom: 0;
}

.page-about .about-steps > li::before {
  content: "";
  position: absolute;
  left: -9px;
  top: 3px;
  width: 15px;
  height: 15px;
  background: var(--accent);
  clip-path: polygon(0 0, 100% 0, 100% 66%, 66% 100%, 0 100%);
}

.page-about .about-steps__time {
  display: inline-block;
  margin-bottom: 6px;
  font-family: var(--font-num);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.14em;
  color: var(--accent);
}

.page-about .about-steps h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
}

.page-about .about-steps p {
  margin: 0;
  max-width: 58ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-dim);
}

.page-about .about-review__media {
  margin: 0;
}

/* ---------- 内容协作 ---------- */
.page-about .about-partners {
  display: grid;
  gap: 32px;
}

.page-about .about-partners__media {
  margin: 0;
}

.page-about .about-partners__stats {
  display: grid;
  gap: 1px;
  background: var(--about-hairline);
  border: 1px solid var(--about-hairline);
  margin-bottom: 26px;
}

.page-about .about-partners__stat {
  display: grid;
  gap: 4px;
  padding: 18px 18px 20px;
  background: var(--ink-700);
  box-shadow: inset 3px 0 0 0 var(--youth);
}

.page-about .about-partners__stat--transfer {
  box-shadow: inset 3px 0 0 0 var(--transfer);
}

.page-about .about-partners__stat .num {
  font-size: clamp(34px, 7vw, 46px);
  line-height: 1;
  color: var(--youth);
}

.page-about .about-partners__stat--transfer .num {
  color: var(--transfer);
}

.page-about .about-partners__stat-label {
  font-size: 14px;
  line-height: 1.6;
  color: var(--text-dim);
}

.page-about .about-partners__list {
  list-style: none;
  margin: 0 0 22px;
  padding: 0;
  display: grid;
  gap: 16px;
}

.page-about .about-partners__list li {
  position: relative;
  padding-left: 18px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-dim);
}

.page-about .about-partners__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  width: 8px;
  height: 2px;
  background: var(--accent);
}

.page-about .about-partners__list strong {
  color: var(--text);
  font-weight: 700;
  margin-right: 6px;
}

.page-about .about-partners__link {
  margin: 0;
}

.page-about .about-partners__link a {
  display: inline-block;
  font-size: 14px;
  font-weight: 700;
  color: var(--accent);
  text-decoration: none;
  border-bottom: 2px solid var(--accent);
  padding-bottom: 2px;
}

.page-about .about-partners__link a:hover {
  color: var(--accent-soft);
  border-bottom-color: var(--accent-soft);
}

.page-about .about-icons {
  display: grid;
  grid-template-columns: repeat(7, minmax(0, 1fr));
  gap: 4px;
  margin-top: 36px;
}

.page-about .about-icons__cell {
  display: block;
  aspect-ratio: 1;
  background: var(--ink-700);
  border: 1px solid var(--about-hairline);
  position: relative;
}

.page-about .about-icons__cell::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  width: 8px;
  height: 8px;
  transform: translate(-50%, -50%) rotate(45deg);
  background: var(--youth);
}

.page-about .about-icons__cell--school::after {
  background: var(--transfer);
}

/* ---------- 长期投入方向 ---------- */
.page-about .about-focus {
  display: grid;
  gap: 0;
  border-top: 1px solid var(--about-hairline);
}

.page-about .about-focus__col {
  padding: 24px 0;
  border-bottom: 1px solid var(--about-hairline);
}

.page-about .about-focus__col h3 {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  line-height: 1.35;
}

.page-about .about-focus__col p {
  margin: 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-dim);
}

/* ---------- 备案与服务地区 ---------- */
.page-about .about-legal {
  display: grid;
  gap: 1px;
  background: var(--about-hairline);
  border: 1px solid var(--about-hairline);
}

.page-about .about-legal__item {
  display: grid;
  gap: 6px;
  padding: 16px 18px;
  background: var(--ink-700);
}

.page-about .about-legal__key {
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--text-dim);
}

.page-about .about-legal__value {
  font-size: 15px;
  line-height: 1.7;
  color: var(--text);
  word-break: break-word;
}

.page-about .about-legal__note {
  margin: 22px 0 0;
  max-width: 66ch;
  font-size: 14px;
  line-height: 1.8;
  color: var(--text-dim);
}

.page-about .about-legal__links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 22px;
  margin: 16px 0 0;
}

.page-about .about-legal__links a {
  font-size: 14px;
  font-weight: 700;
  color: var(--accent);
  text-decoration: none;
  border-bottom: 2px solid var(--accent);
  padding-bottom: 2px;
}

.page-about .about-legal__links a:hover {
  color: var(--accent-soft);
  border-bottom-color: var(--accent-soft);
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-icons {
    grid-template-columns: repeat(14, minmax(0, 1fr));
  }
}

@media (min-width: 720px) {
  .page-about .about-era__summary {
    grid-template-columns: 74px minmax(0, 1fr) 18px;
    gap: 24px;
  }

  .page-about .about-era__year {
    font-size: 26px;
  }

  .page-about .about-era__name {
    font-size: 19px;
  }

  .page-about .about-era__body {
    padding-left: 98px;
  }

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

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

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

  .page-about .about-legal__item--wide {
    grid-column: 1 / -1;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding: 36px 0 72px;
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1fr) 288px;
    gap: 64px;
    align-items: start;
    margin: 32px 0 48px;
  }

  .page-about .about-section {
    padding: 88px 0;
  }

  .page-about .about-section__head {
    margin-bottom: 48px;
  }

  .page-about .about-lines {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: 56px;
  }

  .page-about .about-line:nth-child(even) {
    margin-top: 48px;
  }

  .page-about .about-line {
    border-bottom: 1px solid var(--about-hairline);
  }

  .page-about .about-review {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    gap: 56px;
    align-items: start;
  }

  .page-about .about-partners {
    grid-template-columns: minmax(0, 0.82fr) minmax(0, 1.18fr);
    gap: 56px;
    align-items: start;
  }

  .page-about .about-focus {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    column-gap: 0;
    border-bottom: 1px solid var(--about-hairline);
  }

  .page-about .about-focus__col {
    padding: 28px 28px 32px 0;
    border-bottom: none;
    border-right: 1px solid var(--about-hairline);
  }

  .page-about .about-focus__col:last-child {
    border-right: none;
    padding-right: 0;
  }
}

@media (min-width: 1080px) {
  .page-about .about-team__matrix {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1fr) 320px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-era__name,
  .page-about .about-era__toggle::before,
  .page-about .about-era__toggle::after {
    transition: none;
  }
}
</main>