.page-about {
  --ab-hair: var(--sx-line);
  --ab-dim: var(--sx-muted);
  --ab-card: rgba(22, 34, 74, 0.62);
  padding-bottom: 72px;
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumb {
  padding-top: 18px;
}

.page-about .breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 13px;
  color: var(--ab-dim);
}

.page-about .breadcrumb__item a {
  color: var(--ab-dim);
  text-decoration: none;
  transition: color 0.24s var(--sx-ease);
}

.page-about .breadcrumb__item a:hover {
  color: var(--sx-lime);
}

.page-about .breadcrumb__item [aria-current="page"] {
  color: var(--sx-text);
}

/* ---------- 通用小标题 ---------- */
.page-about .section__eyebrow {
  margin: 0;
  font-family: var(--sx-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--sx-cyan);
}

.page-about .section__lead {
  margin: 14px 0 0;
  font-size: 15px;
  line-height: 1.9;
  color: var(--ab-dim);
  max-width: 68ch;
}

.page-about h2 {
  font-family: var(--sx-head);
  font-weight: 800;
  font-size: clamp(22px, 4.4vw, 30px);
  line-height: 1.25;
  letter-spacing: -0.01em;
  color: #fff;
  margin: 12px 0 0;
}

.page-about h3 {
  font-family: var(--sx-head);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.4;
  color: var(--sx-text);
  margin: 0 0 8px;
}

.page-about p {
  margin: 0;
}

.page-about a {
  color: var(--sx-lime);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-top: 10px;
}

.page-about .about-hero__head {
  max-width: 840px;
  padding: 20px 0 28px;
}

.page-about .about-hero h1 {
  font-family: var(--sx-head);
  font-weight: 800;
  font-size: clamp(30px, 7.2vw, 50px);
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: #fff;
  margin: 14px 0 18px;
}

.page-about .about-hero__lede {
  font-size: 16px;
  line-height: 1.85;
  color: var(--sx-text);
  max-width: 66ch;
}

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

.page-about .about-hero__figure {
  position: relative;
  margin: 6px var(--sx-gutter) 0;
  border: 1px solid var(--ab-hair);
  border-radius: var(--sx-r-lg);
  overflow: hidden;
  background: var(--sx-glow);
}

.page-about .about-hero__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 1920 / 720;
  object-fit: cover;
}

.page-about .about-hero__figure::after {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: linear-gradient(90deg, var(--sx-cyan), transparent 72%);
}

.page-about .about-figure__caption {
  padding: 10px 16px 14px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--ab-dim);
}

/* ---------- 发展轨迹 ---------- */
.page-about .about-track {
  padding-top: 76px;
}

.page-about .about-track__head {
  max-width: 720px;
  margin-bottom: 36px;
}

.page-about .track-layout {
  display: grid;
  gap: 26px;
}

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

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

.page-about .track-rail__list a {
  display: block;
  padding: 9px 15px;
  border: 1px solid var(--ab-hair);
  border-radius: 999px;
  font-family: var(--sx-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--ab-dim);
  text-decoration: none;
  white-space: nowrap;
  transition: color 0.24s var(--sx-ease), border-color 0.24s var(--sx-ease),
    background-color 0.24s var(--sx-ease);
}

.page-about .track-rail__list a:hover,
.page-about .track-rail__list a.is-current {
  color: var(--sx-night);
  background: var(--sx-lime);
  border-color: var(--sx-lime);
}

.page-about .phase {
  position: relative;
  padding: 0 0 26px 58px;
}

.page-about .phase::before {
  content: "";
  position: absolute;
  left: 16px;
  top: 36px;
  bottom: 0;
  width: 2px;
  background: linear-gradient(180deg, var(--sx-cyan), rgba(47, 227, 196, 0));
}

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

.page-about .phase:last-child::before {
  display: none;
}

.page-about .phase__node {
  position: absolute;
  left: 0;
  top: 0;
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 12px;
  border: 1px solid var(--ab-hair);
  background: var(--sx-panel);
  font-family: var(--sx-mono);
  font-size: 11px;
  font-weight: 700;
  color: var(--sx-cyan);
}

.page-about .phase:nth-child(2) .phase__node {
  width: 38px;
  height: 38px;
  border-radius: 15px;
}

.page-about .phase:nth-child(3) .phase__node {
  width: 30px;
  height: 30px;
  border-radius: 10px;
}

.page-about .phase__body {
  position: relative;
  overflow: hidden;
  padding: 20px 20px 18px;
  border: 1px solid var(--ab-hair);
  border-radius: var(--sx-r);
  background: var(--ab-card);
  transition: border-color 0.24s var(--sx-ease), transform 0.24s var(--sx-ease);
}

.page-about .phase__body::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: linear-gradient(90deg, var(--sx-cyan), rgba(47, 227, 196, 0) 70%);
}

.page-about .phase__body:hover {
  border-color: rgba(124, 255, 107, 0.45);
  transform: translateY(-2px);
}

.page-about .phase__title {
  margin-bottom: 10px;
}

.page-about .phase__text {
  font-size: 15px;
  line-height: 1.85;
  color: var(--ab-dim);
}

.page-about .phase__meta {
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px solid var(--ab-hair);
  font-family: var(--sx-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--sx-amber);
}

/* ---------- 数据带 ---------- */
.page-about .about-stats {
  padding-top: 44px;
}

.page-about .stat-strip {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px 18px;
  padding: 30px 22px;
  border: 1px solid var(--ab-hair);
  border-radius: var(--sx-r-lg);
  background: var(--sx-glow);
  position: relative;
  overflow: hidden;
}

.page-about .stat-strip::after {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: linear-gradient(90deg, var(--sx-cyan), var(--sx-lime), rgba(124, 255, 107, 0));
}

.page-about .stat-strip__item {
  display: flex;
  flex-direction: column;
  gap: 8px;
  min-width: 0;
}

.page-about .stat-strip__num {
  font-family: var(--sx-mono);
  font-size: clamp(30px, 7vw, 46px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--sx-lime);
}

.page-about .stat-strip__label {
  font-size: 13px;
  line-height: 1.6;
  color: var(--ab-dim);
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  padding-top: 76px;
}

.page-about .about-team__head {
  max-width: 760px;
  margin-bottom: 32px;
}

.page-about .team-layout {
  display: grid;
  gap: 24px;
}

.page-about .team-matrix {
  display: grid;
  grid-template-columns: 1fr;
  grid-template-areas:
    "a"
    "b"
    "c"
    "d";
  gap: 14px;
}

.page-about .team-cell--a {
  grid-area: a;
}

.page-about .team-cell--b {
  grid-area: b;
}

.page-about .team-cell--c {
  grid-area: c;
}

.page-about .team-cell--d {
  grid-area: d;
}

.page-about .team-cell {
  position: relative;
  padding: 18px 18px 42px;
  border: 1px solid var(--ab-hair);
  border-radius: var(--sx-r);
  background: var(--ab-card);
  min-width: 0;
  transition: border-color 0.24s var(--sx-ease), background-color 0.24s var(--sx-ease);
}

.page-about .team-cell:hover,
.page-about .team-cell:focus-within {
  border-color: rgba(124, 255, 107, 0.5);
  background: rgba(22, 34, 74, 0.85);
}

.page-about .team-cell__desc {
  font-size: 14px;
  line-height: 1.8;
  color: var(--ab-dim);
}

.page-about .team-cell__note {
  margin-top: 10px;
  font-size: 12px;
  line-height: 1.6;
  color: var(--ab-dim);
  opacity: 0.5;
  transition: opacity 0.24s var(--sx-ease), color 0.24s var(--sx-ease);
}

.page-about .team-cell:hover .team-cell__note,
.page-about .team-cell:focus-within .team-cell__note {
  opacity: 1;
  color: var(--sx-lime);
}

.page-about .team-cell__num {
  position: absolute;
  right: 16px;
  bottom: 12px;
  font-family: var(--sx-mono);
  font-size: 22px;
  font-weight: 700;
  color: rgba(159, 176, 208, 0.35);
}

.page-about .team-figure,
.page-about .source-figure {
  margin: 0;
  border: 1px solid var(--ab-hair);
  border-radius: var(--sx-r-lg);
  overflow: hidden;
  background: var(--sx-glow);
}

.page-about .team-figure img,
.page-about .source-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

/* ---------- 覆盖范围 ---------- */
.page-about .about-coverage {
  padding-top: 76px;
}

.page-about .about-coverage__head {
  max-width: 720px;
  margin-bottom: 30px;
}

.page-about .coverage-grid {
  display: grid;
  gap: 22px;
}

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

.page-about .league-item {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  gap: 14px;
  padding: 18px;
  border: 1px solid var(--ab-hair);
  border-radius: var(--sx-r);
  background: var(--ab-card);
}

.page-about .league-item__num {
  font-family: var(--sx-mono);
  font-size: 14px;
  font-weight: 700;
  color: var(--sx-cyan);
  padding-top: 2px;
}

.page-about .league-item p {
  font-size: 14px;
  line-height: 1.8;
  color: var(--ab-dim);
}

.page-about .coverage-fields {
  padding: 22px 20px;
  border-radius: var(--sx-r);
  background: var(--ab-card);
}

.page-about .coverage-fields__title {
  margin-bottom: 14px;
}

.page-about .field-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 16px;
  padding: 0;
  list-style: none;
}

.page-about .field-list__item {
  padding: 7px 14px;
  border-radius: 999px;
  border: 1px solid rgba(47, 227, 196, 0.4);
  font-family: var(--sx-mono);
  font-size: 12px;
  color: var(--sx-cyan);
}

.page-about .coverage-fields__note {
  font-size: 14px;
  line-height: 1.85;
  color: var(--ab-dim);
}

/* ---------- 资料来源 ---------- */
.page-about .about-source {
  padding-top: 76px;
}

.page-about .source-layout {
  display: grid;
  gap: 26px;
}

.page-about .source-copy h2 {
  margin-bottom: 12px;
}

.page-about .source-list {
  display: grid;
  gap: 14px;
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .source-item {
  position: relative;
  padding: 16px 18px 16px 56px;
  border: 1px solid var(--ab-hair);
  border-left: 2px solid var(--sx-cyan);
  border-radius: var(--sx-r-sm);
  background: var(--ab-card);
  transition: border-left-color 0.24s var(--sx-ease);
}

.page-about .source-item:hover {
  border-left-color: var(--sx-lime);
}

.page-about .source-item__num {
  position: absolute;
  left: 18px;
  top: 17px;
  font-family: var(--sx-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--sx-lime);
}

.page-about .source-item__title {
  font-size: 16px;
  margin-bottom: 6px;
}

.page-about .source-item p {
  font-size: 14px;
  line-height: 1.8;
  color: var(--ab-dim);
}

/* ---------- 使用场景 ---------- */
.page-about .about-usage {
  padding-top: 76px;
}

.page-about .usage-layout {
  display: grid;
  gap: 26px;
}

.page-about .usage-copy h2 {
  margin-bottom: 16px;
}

.page-about .usage-copy p {
  font-size: 15px;
  line-height: 1.9;
  color: var(--ab-dim);
  margin-bottom: 14px;
  max-width: 66ch;
}

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

.page-about .usage-links a {
  text-decoration: none;
  border-bottom: 1px solid rgba(124, 255, 107, 0.5);
}

.page-about .usage-links a:hover {
  border-bottom-color: var(--sx-lime);
}

.page-about .usage-badge {
  padding: 28px 24px;
  border: 1px solid var(--ab-hair);
  border-radius: var(--sx-r-lg);
  background: var(--sx-glow);
  position: relative;
  overflow: hidden;
  align-self: start;
}

.page-about .usage-badge::after {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: linear-gradient(90deg, var(--sx-orange), rgba(255, 122, 47, 0));
}

.page-about .usage-badge__num {
  display: block;
  font-family: var(--sx-mono);
  font-size: clamp(36px, 8vw, 54px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--sx-orange);
}

.page-about .usage-badge__label {
  display: block;
  margin-top: 10px;
  font-size: 14px;
  color: var(--sx-text);
}

.page-about .usage-badge__note {
  margin-top: 14px;
  padding-top: 14px;
  border-top: 1px solid var(--ab-hair);
  font-size: 13px;
  line-height: 1.8;
  color: var(--ab-dim);
}

/* ---------- 结尾 ---------- */
.page-about .about-cta {
  margin-top: 76px;
  padding: 32px 22px;
  border: 1px solid var(--ab-hair);
  border-radius: var(--sx-r-lg);
  background: var(--sx-glow);
}

.page-about .about-cta h2 {
  max-width: 26ch;
}

.page-about .about-cta__text {
  margin-top: 14px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ab-dim);
  max-width: 60ch;
}

/* ---------- 平板 ---------- */
@media (min-width: 640px) {
  .page-about .about-hero__figure {
    margin-left: auto;
    margin-right: auto;
    max-width: calc(var(--sx-shell) + 40px);
    padding: 0 20px;
    border: 0;
    border-radius: 0;
    background: none;
    overflow: visible;
  }

  .page-about .about-hero__figure img {
    border-radius: var(--sx-r-lg);
    border: 1px solid var(--ab-hair);
  }

  .page-about .about-hero__figure::after {
    display: none;
  }

  .page-about .team-matrix {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    grid-template-areas:
      "a b"
      "c d";
  }

  .page-about .stat-strip {
    padding: 36px 30px;
    gap: 26px;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 900px) {
  .page-about {
    padding-bottom: 96px;
  }

  .page-about .about-track {
    padding-top: 96px;
  }

  .page-about .track-layout {
    grid-template-columns: 212px minmax(0, 1fr);
    gap: 46px;
    align-items: start;
  }

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

  .page-about .track-rail__list {
    display: block;
    overflow: visible;
    padding: 0;
    border-left: 1px solid var(--ab-hair);
  }

  .page-about .track-rail__list li + li {
    margin-top: 4px;
  }

  .page-about .track-rail__list a {
    border: 0;
    border-radius: 0 999px 999px 0;
    border-left: 2px solid transparent;
    margin-left: -1px;
    padding: 10px 14px;
    white-space: normal;
  }

  .page-about .track-rail__list a:hover,
  .page-about .track-rail__list a.is-current {
    background: rgba(124, 255, 107, 0.1);
    color: var(--sx-lime);
    border-left-color: var(--sx-lime);
  }

  .page-about .phase:nth-child(even) {
    margin-left: 8%;
  }

  .page-about .about-stats {
    padding-top: 64px;
  }

  .page-about .stat-strip {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    padding: 44px 40px;
  }

  .page-about .about-team,
  .page-about .about-coverage,
  .page-about .about-source,
  .page-about .about-usage {
    padding-top: 96px;
  }

  .page-about .team-layout {
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 0.85fr);
    gap: 30px;
    align-items: start;
  }

  .page-about .coverage-grid {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 0.9fr);
    gap: 26px;
    align-items: start;
  }

  .page-about .source-layout {
    grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.2fr);
    gap: 40px;
    align-items: start;
  }

  .page-about .usage-layout {
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 0.8fr);
    gap: 40px;
    align-items: center;
  }

  .page-about .about-cta {
    padding: 48px 44px;
  }
}

@media (min-width: 1200px) {
  .page-about .about-hero {
    padding-top: 24px;
  }

  .page-about .phase:nth-child(even) {
    margin-left: 12%;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }
}