.page-about {
  --about-line: var(--graphite-700);
  --about-gap: clamp(18px, 3vw, 30px);
  --about-shadow: 0 18px 44px rgba(4, 8, 18, .45);
  display: block;
  position: relative;
}

/* ---------- 面包屑与区块标题 ---------- */
.page-about .breadcrumb {
  margin-bottom: clamp(20px, 3vw, 32px);
  font-size: 13px;
}

.page-about .sec-head {
  max-width: 780px;
  margin-bottom: var(--about-gap);
}

.page-about .sec-index {
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--track-orange);
  margin: 0 0 10px;
}

.page-about .sec-title {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(23px, 3.6vw, 32px);
  line-height: 1.16;
  letter-spacing: -.02em;
  color: var(--white-000);
  margin: 0;
}

.page-about .prose-lead {
  margin: 14px 0 0;
  font-size: 16px;
  line-height: 1.75;
  color: var(--slate-200);
}

.page-about .prose p {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.78;
  color: var(--slate-200);
}

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

.page-about a {
  color: var(--signal-cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(37, 240, 212, .38);
  transition: border-color var(--dur-fast) var(--ease), color var(--dur-fast) var(--ease);
}

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

.page-about a:focus-visible {
  outline: 2px solid var(--signal-cyan);
  outline-offset: 3px;
  border-radius: 3px;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding-block: clamp(26px, 4vw, 48px) clamp(40px, 6vw, 76px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, rgba(38, 49, 63, .6) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(38, 49, 63, .6) 1px, transparent 1px);
  background-size: 64px 64px;
  -webkit-mask-image: radial-gradient(120% 78% at 72% 6%, #000 0%, transparent 72%);
  mask-image: radial-gradient(120% 78% at 72% 6%, #000 0%, transparent 72%);
  pointer-events: none;
  z-index: 0;
}

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

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(24px, 4vw, 44px);
  align-items: center;
}

.page-about .about-hero__copy .eyebrow {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: .18em;
  color: var(--signal-cyan);
}

.page-about .about-hero__copy h1 {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(30px, 6vw, 52px);
  line-height: 1.1;
  letter-spacing: -.025em;
  color: var(--white-000);
}

.page-about .about-hero__copy .lead {
  margin: 18px 0 0;
  max-width: 60ch;
  font-size: 16.5px;
  line-height: 1.78;
  color: var(--slate-200);
}

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

.page-about .about-hero__visual svg {
  display: block;
  width: 100%;
  height: auto;
  filter: drop-shadow(0 12px 30px rgba(37, 240, 212, .12));
}

/* ---------- 统计条 ---------- */
.page-about .stat-row {
  margin-top: clamp(30px, 5vw, 52px);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--about-line);
  border: 1px solid var(--about-line);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.page-about .stat {
  position: relative;
  background: var(--panel-600);
  padding: 24px 16px 18px;
}

.page-about .stat::before {
  content: "";
  position: absolute;
  left: 16px;
  top: 14px;
  width: 20px;
  height: 2px;
  border-radius: 2px;
  background: var(--signal-cyan);
}

.page-about .stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(24px, 4.4vw, 34px);
  font-weight: 600;
  letter-spacing: .04em;
  color: var(--white-000);
  line-height: 1.1;
}

.page-about .stat-label {
  display: block;
  margin-top: 8px;
  font-size: 13px;
  letter-spacing: .04em;
  color: var(--muted-400);
}

/* ---------- 媒体容器 ---------- */
.page-about .media-frame {
  margin: 0;
  position: relative;
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--about-line);
  background: var(--charcoal-850);
}

.page-about .media-frame img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .media-frame__label {
  position: absolute;
  left: 14px;
  bottom: 12px;
  padding: 5px 11px;
  border-radius: var(--radius-pill);
  background: rgba(10, 16, 32, .82);
  border: 1px solid var(--about-line);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .1em;
  color: var(--signal-cyan);
}

/* ---------- 01 起点与主张 ---------- */
.page-about .about-origin .origin-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 3.6vw, 40px);
  align-items: start;
}

/* ---------- 02 内容体系 ---------- */
.page-about .cat-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .cat-card {
  position: relative;
  overflow: hidden;
  padding: 22px 20px 24px;
  background: var(--panel-600);
  border: 1px solid var(--about-line);
  border-radius: var(--radius-md);
  transition: transform var(--dur-base) var(--ease), border-color var(--dur-base) var(--ease);
}

.page-about .cat-card::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: linear-gradient(90deg, var(--signal-cyan), rgba(37, 240, 212, 0));
}

.page-about .cat-card--b::before {
  background: linear-gradient(90deg, var(--track-orange), rgba(255, 106, 43, 0));
}

.page-about .cat-card--c::before {
  background: linear-gradient(90deg, var(--volt-violet), rgba(138, 107, 255, 0));
}

.page-about .cat-card--d::before {
  background: linear-gradient(90deg, var(--alert-yellow), rgba(255, 210, 63, 0));
}

.page-about .cat-card:hover {
  transform: translateY(-3px);
  border-color: rgba(37, 240, 212, .5);
}

.page-about .cat-card__code {
  margin: 0 0 12px;
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--muted-400);
}

.page-about .cat-card__title {
  margin: 0 0 10px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(18px, 2.4vw, 20px);
  letter-spacing: -.01em;
  color: var(--white-000);
}

.page-about .cat-card__text {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.72;
  color: var(--slate-200);
}

/* ---------- 03 赛季轨迹 ---------- */
.page-about .season-banner {
  margin-bottom: clamp(26px, 4vw, 40px);
}

.page-about .season-track {
  position: relative;
  padding-left: 26px;
}

.page-about .season-track::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--track-orange), var(--signal-cyan) 55%, rgba(38, 49, 63, .9));
}

.page-about .season-phase {
  position: relative;
  margin-bottom: 12px;
  border-radius: var(--radius-md);
}

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

.page-about .season-phase::before {
  content: "";
  position: absolute;
  left: -24px;
  top: 19px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--ink-900);
  border: 2px solid var(--track-orange);
}

.page-about .season-phase:nth-child(2)::before {
  border-color: var(--signal-cyan);
}

.page-about .season-phase:nth-child(3)::before {
  border-color: var(--volt-violet);
}

.page-about .season-phase > summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 12px;
  padding: 14px 18px;
  background: var(--panel-600);
  border: 1px solid var(--about-line);
  border-radius: var(--radius-md);
  transition: border-color var(--dur-fast) var(--ease);
}

.page-about .season-phase > summary::-webkit-details-marker {
  display: none;
}

.page-about .season-phase > summary:hover {
  border-color: rgba(37, 240, 212, .5);
}

.page-about .season-phase > summary::after {
  content: "＋";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--signal-cyan);
}

.page-about .season-phase[open] > summary::after {
  content: "－";
}

.page-about .season-phase > summary:focus-visible {
  outline: 2px solid var(--signal-cyan);
  outline-offset: 3px;
}

.page-about .season-phase__no {
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--track-orange);
}

.page-about .season-phase__name {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(15.5px, 2.1vw, 18px);
  letter-spacing: -.01em;
  color: var(--white-000);
}

.page-about .season-list {
  list-style: none;
  margin: 14px 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .season-list li {
  position: relative;
  padding-left: 22px;
  font-size: 15.5px;
  line-height: 1.74;
  color: var(--slate-200);
}

.page-about .season-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .66em;
  width: 11px;
  height: 2px;
  border-radius: 2px;
  background: var(--signal-cyan);
}

/* ---------- 04 团队与协作 ---------- */
.page-about .eco-band {
  position: relative;
  padding: clamp(22px, 4vw, 44px);
  border: 1px solid var(--about-line);
  border-radius: var(--radius-lg);
  background:
    radial-gradient(circle at 16% 24%, rgba(37, 240, 212, .11), transparent 46%),
    radial-gradient(circle at 84% 74%, rgba(138, 107, 255, .13), transparent 52%),
    var(--charcoal-850);
}

.page-about .eco-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 3.6vw, 40px);
  align-items: center;
}

.page-about .eco-copy .sec-index {
  color: var(--volt-violet);
}

.page-about .eco-copy .prose-lead {
  margin-bottom: 14px;
}

.page-about .eco-copy p {
  margin: 0 0 14px;
  font-size: 15.5px;
  line-height: 1.78;
  color: var(--slate-200);
}

.page-about .eco-points {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .eco-points li {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--about-line);
  background: rgba(27, 36, 50, .72);
  font-size: 15px;
  line-height: 1.6;
  color: var(--slate-200);
}

.page-about .eco-points__num {
  flex: 0 0 auto;
  font-size: 18px;
  font-weight: 600;
  letter-spacing: .04em;
  color: var(--signal-cyan);
}

/* ---------- 05 内容维护 ---------- */
.page-about .audit-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .audit-card {
  padding: 22px 20px;
  border-radius: var(--radius-md);
  border: 1px solid var(--about-line);
  background: linear-gradient(160deg, rgba(37, 240, 212, .07), rgba(27, 36, 50, .9) 42%);
}

.page-about .audit-card__num {
  margin: 0 0 10px;
  font-size: clamp(28px, 4.6vw, 38px);
  font-weight: 600;
  letter-spacing: .04em;
  line-height: 1;
  color: var(--white-000);
}

.page-about .audit-card:nth-child(2) .audit-card__num {
  color: var(--alert-yellow);
}

.page-about .audit-card:nth-child(3) .audit-card__num {
  color: var(--track-orange);
}

.page-about .audit-card:nth-child(4) .audit-card__num {
  color: var(--volt-violet);
}

.page-about .audit-card__title {
  margin: 0 0 10px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 17.5px;
  letter-spacing: -.01em;
  color: var(--white-000);
}

.page-about .audit-card__text {
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--slate-200);
}

.page-about .audit-foot {
  margin: clamp(22px, 3.4vw, 32px) 0 0;
  padding-top: 18px;
  border-top: 1px solid var(--about-line);
  font-size: 15px;
  line-height: 1.75;
  color: var(--muted-400);
}

/* ---------- 06 长期维护 ---------- */
.page-about .commit-card {
  padding: clamp(22px, 4vw, 42px);
  border-radius: var(--radius-lg);
  border: 1px solid var(--about-line);
  background:
    linear-gradient(115deg, rgba(255, 106, 43, .12) 0%, rgba(10, 16, 32, 0) 42%),
    var(--panel-600);
}

.page-about .commit-copy p {
  margin: 14px 0 0;
  max-width: 68ch;
  font-size: 16px;
  line-height: 1.78;
  color: var(--slate-200);
}

.page-about .commit-list {
  list-style: none;
  margin: clamp(22px, 3.4vw, 30px) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--about-line);
  border: 1px solid var(--about-line);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.page-about .commit-list li {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 14px;
  padding: 14px 16px;
  background: var(--charcoal-850);
  font-size: 15px;
  line-height: 1.6;
  color: var(--slate-200);
}

.page-about .commit-k {
  flex: 0 0 auto;
  font-size: 12.5px;
  letter-spacing: .14em;
  color: var(--track-orange);
}

.page-about .commit-actions {
  margin-top: clamp(22px, 3.4vw, 30px);
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 700px) {
  .page-about .stat-row {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

@media (min-width: 860px) {
  .page-about .cat-grid {
    grid-template-columns: repeat(12, minmax(0, 1fr));
  }

  .page-about .cat-card--a {
    grid-column: span 5;
  }

  .page-about .cat-card--b {
    grid-column: span 7;
  }

  .page-about .cat-card--c {
    grid-column: span 7;
  }

  .page-about .cat-card--d {
    grid-column: span 5;
  }
}

@media (min-width: 960px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, .88fr);
    gap: clamp(32px, 4vw, 60px);
  }

  .page-about .origin-grid {
    grid-template-columns: minmax(0, .92fr) minmax(0, 1.08fr);
    gap: clamp(30px, 4vw, 54px);
  }

  .page-about .eco-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.06fr);
  }

  .page-about .eco-grid .media-frame {
    order: 2;
  }

  .page-about .season-track {
    padding-left: 34px;
  }

  .page-about .season-track::before {
    left: 9px;
  }

  .page-about .season-phase::before {
    left: -31px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .cat-card,
  .page-about .season-phase > summary {
    transition: none;
  }

  .page-about .cat-card:hover {
    transform: none;
  }
}