.page-about {
  --about-text: #C9D3DE;
  --about-soft: rgba(230, 235, 239, 0.64);
  --about-line: rgba(230, 235, 239, 0.14);
  background: var(--ink-900);
  color: var(--fog);
  padding-bottom: clamp(40px, 6vw, 88px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(20px, 4vw, 40px) 0 clamp(32px, 5vw, 64px);
  border-bottom: 1px solid var(--about-line);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: -30% -20% auto -20%;
  height: 640px;
  pointer-events: none;
  background:
    radial-gradient(45% 55% at 18% 8%, rgba(55, 245, 228, 0.18), transparent 70%),
    radial-gradient(40% 50% at 88% 0%, rgba(155, 92, 255, 0.16), transparent 72%),
    radial-gradient(35% 40% at 58% 26%, rgba(255, 107, 53, 0.09), transparent 70%);
}

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

.page-about .breadcrumbs ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0 0 24px;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.02em;
  color: var(--rock);
}

.page-about .breadcrumbs li + li::before {
  content: "/";
  margin-right: 8px;
  color: rgba(138, 149, 166, 0.5);
}

.page-about .breadcrumbs a {
  color: var(--rock);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.page-about .breadcrumbs a:hover,
.page-about .breadcrumbs a:focus-visible {
  color: var(--cyan);
  border-bottom-color: rgba(55, 245, 228, 0.6);
}

.page-about .hero-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
}

.page-about .hero-copy h1 {
  margin: 0.35em 0 0.5em;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2.1rem, 6vw, 4rem);
  line-height: 1.05;
  letter-spacing: -0.02em;
}

.page-about .hero-copy h1 em {
  font-style: normal;
  color: var(--cyan);
  display: inline-block;
  transform: skew(-4deg);
}

.page-about .lede {
  max-width: 46ch;
  margin: 0 0 26px;
  font-size: clamp(0.98rem, 1.8vw, 1.08rem);
  line-height: 1.85;
  color: var(--about-text);
}

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

.page-about .hero-panel {
  align-self: start;
  padding: 22px;
  border: 1px solid var(--about-line);
  border-radius: var(--radius-lg);
  background: linear-gradient(160deg, var(--ink-800), var(--ink-850));
}

.page-about .panel-label {
  margin: 0 0 16px;
  font-size: 0.74rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--violet);
}

.page-about .hero-stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .hero-stats li {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding-left: 12px;
  border-left: 1px solid rgba(55, 245, 228, 0.28);
}

.page-about .stat-num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(1.5rem, 4vw, 2rem);
  line-height: 1;
  color: var(--cyan);
  font-variant-numeric: tabular-nums;
}

.page-about .stat-unit {
  font-size: 0.62em;
  margin-left: 2px;
}

.page-about .stat-label {
  font-size: 0.74rem;
  line-height: 1.4;
  color: var(--rock);
}

.page-about .panel-note {
  margin: 18px 0 0;
  padding-top: 14px;
  border-top: 1px dashed rgba(230, 235, 239, 0.16);
  font-size: 0.82rem;
  line-height: 1.7;
  color: var(--about-soft);
}

/* ---------- 目录 + 正文骨架 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: 1fr;
  gap: 26px;
  padding-top: clamp(28px, 4vw, 52px);
}

.page-about .about-index {
  display: block;
}

.page-about .index-title {
  display: none;
  margin: 0 0 12px;
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--rock);
}

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

.page-about .index-list a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 15px;
  white-space: nowrap;
  border: 1px solid var(--about-line);
  border-radius: var(--radius-pill);
  background: rgba(16, 26, 44, 0.6);
  color: var(--about-soft);
  font-size: 0.82rem;
  text-decoration: none;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease), background 0.18s var(--ease);
}

.page-about .index-list a .mono {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--cyan);
  opacity: 0.8;
}

.page-about .index-list a:hover,
.page-about .index-list a:focus-visible {
  color: var(--fog);
  border-color: rgba(55, 245, 228, 0.5);
  background: rgba(55, 245, 228, 0.08);
}

.page-about .about-sec {
  padding: clamp(26px, 4vw, 44px) 0;
  border-top: 1px solid var(--about-line);
  scroll-margin-top: calc(var(--header-h) + 20px);
}

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

.page-about .sec-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 16px;
  margin-bottom: 18px;
}

.page-about .sec-num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(1.9rem, 5vw, 3.2rem);
  line-height: 0.9;
  color: rgba(55, 245, 228, 0.34);
  letter-spacing: -0.02em;
}

.page-about .sec-title {
  flex: 1 1 14ch;
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.35rem, 3.2vw, 2.1rem);
  line-height: 1.2;
  letter-spacing: -0.01em;
  color: var(--fog);
}

.page-about .about-sec > p {
  max-width: 62ch;
  margin: 0 0 15px;
  font-size: clamp(0.95rem, 1.6vw, 1.02rem);
  line-height: 1.88;
  color: var(--about-text);
}

/* ---------- 通用条目列表 ---------- */
.page-about .fact-list {
  display: grid;
  gap: 1px;
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
  border-radius: var(--radius-md);
  overflow: hidden;
  background: var(--about-line);
}

.page-about .fact-list li {
  display: grid;
  grid-template-columns: 68px minmax(0, 1fr);
  gap: 12px;
  align-items: baseline;
  padding: 14px 16px;
  background: var(--ink-850);
  font-size: 0.92rem;
  line-height: 1.75;
  color: var(--about-text);
}

.page-about .fact-key {
  font-size: 0.76rem;
  letter-spacing: 0.1em;
  color: var(--cyan);
}

/* ---------- 媒体 ---------- */
.page-about .media-frame {
  margin: 22px 0 24px;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--about-line);
}

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

.page-about .media-caption {
  display: block;
  padding: 12px 16px;
  font-size: 0.8rem;
  line-height: 1.7;
  color: var(--rock);
  background: rgba(16, 26, 44, 0.82);
  border-top: 1px solid var(--about-line);
}

/* ---------- 团队 ---------- */
.page-about .team-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.page-about .team-card {
  padding: 20px 18px;
  border: 1px solid var(--about-line);
  border-radius: var(--radius-md);
  background: linear-gradient(170deg, var(--ink-800), var(--ink-850));
  transition: transform 0.2s var(--ease), border-color 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.page-about .team-card:hover,
.page-about .team-card:focus-visible {
  transform: translateY(-3px);
  border-color: rgba(55, 245, 228, 0.5);
  box-shadow: 0 14px 32px -20px rgba(55, 245, 228, 0.7);
  outline: none;
}

.page-about .team-num {
  margin: 0 0 6px;
  font-size: 2rem;
  font-weight: 700;
  line-height: 1;
  color: var(--cyan);
  font-variant-numeric: tabular-nums;
}

.page-about .team-name {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.02rem;
  color: var(--fog);
}

.page-about .team-text {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.8;
  color: var(--about-text);
}

/* ---------- 流程 ---------- */
.page-about .flow {
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .flow-step {
  padding: 18px;
  border: 1px solid var(--about-line);
  border-left: 2px solid rgba(55, 245, 228, 0.5);
  border-radius: var(--radius-md);
  background: rgba(16, 26, 44, 0.66);
}

.page-about .flow-num {
  display: block;
  margin-bottom: 6px;
  font-size: 0.74rem;
  letter-spacing: 0.14em;
  color: var(--lava);
}

.page-about .flow-title {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1rem;
  color: var(--fog);
}

.page-about .flow-text {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.78;
  color: var(--about-text);
}

/* ---------- 合作网络 ---------- */
.page-about .network-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  margin-top: 22px;
}

.page-about .net-item {
  padding: 18px 16px;
  border: 1px solid var(--about-line);
  border-radius: var(--radius-md);
  background: var(--ink-850);
}

.page-about .net-num {
  margin: 0 0 4px;
  font-size: clamp(1.6rem, 4vw, 2.2rem);
  font-weight: 700;
  line-height: 1;
  color: var(--fog);
  font-variant-numeric: tabular-nums;
}

.page-about .net-item:nth-child(2) .net-num { color: var(--cyan); }
.page-about .net-item:nth-child(3) .net-num { color: var(--clay); }
.page-about .net-item:nth-child(4) .net-num { color: var(--moss-soft); }

.page-about .net-label {
  margin: 0;
  font-size: 0.82rem;
  line-height: 1.5;
  color: var(--rock);
}

.page-about .region-block {
  margin-top: 20px;
  padding: 18px;
  border: 1px solid var(--about-line);
  border-radius: var(--radius-md);
  background: linear-gradient(120deg, rgba(55, 245, 228, 0.06), rgba(155, 92, 255, 0.06));
}

.page-about .region-caption {
  margin: 0 0 14px;
  font-size: 0.84rem;
  line-height: 1.7;
  color: var(--about-soft);
}

.page-about .region-dots {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.page-about .region-dots span {
  width: 16px;
  height: 16px;
  border-radius: 4px;
  background: rgba(55, 245, 228, 0.16);
  border: 1px solid rgba(55, 245, 228, 0.26);
  transition: background 0.18s var(--ease), transform 0.18s var(--ease);
}

.page-about .region-dots span:nth-child(3n) {
  background: rgba(216, 205, 187, 0.16);
  border-color: rgba(216, 205, 187, 0.28);
}

.page-about .region-dots span:hover {
  background: var(--cyan);
  transform: scale(1.18);
}

/* ---------- 时间轴 ---------- */
.page-about .version-figure {
  margin-top: 18px;
}

.page-about .version-figure img {
  max-height: 260px;
}

.page-about .timeline {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: 76%;
  gap: 12px;
  margin: 0;
  padding: 4px 0 12px;
  list-style: none;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
}

.page-about .timeline li {
  scroll-snap-align: start;
  padding: 18px 16px;
  border: 1px solid var(--about-line);
  border-radius: var(--radius-md);
  background: var(--ink-850);
  transition: border-color 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.page-about .timeline li::before {
  content: "";
  display: block;
  width: 28px;
  height: 2px;
  margin-bottom: 12px;
  border-radius: 2px;
  background: var(--cyan);
  box-shadow: 0 0 12px rgba(55, 245, 228, 0.75);
}

.page-about .timeline li:hover,
.page-about .timeline li:focus-visible {
  border-color: rgba(55, 245, 228, 0.5);
  box-shadow: 0 14px 30px -22px rgba(55, 245, 228, 0.8);
  outline: 2px solid var(--violet);
  outline-offset: 3px;
}

.page-about .tl-year {
  margin: 0 0 6px;
  font-size: 0.78rem;
  letter-spacing: 0.1em;
  color: var(--cyan);
}

.page-about .tl-title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1rem;
  color: var(--fog);
}

.page-about .tl-text {
  margin: 0;
  font-size: 0.86rem;
  line-height: 1.78;
  color: var(--about-text);
}

/* ---------- 原则 ---------- */
.page-about .principles {
  margin-top: 6px;
  padding: clamp(22px, 4vw, 38px);
  border-radius: var(--radius-xl);
  background: linear-gradient(150deg, var(--clay), #C7B9A2);
  color: #1F170E;
}

.page-about .principles-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .principles-list li {
  padding-left: 16px;
  border-left: 3px solid rgba(31, 23, 14, 0.35);
}

.page-about .principles-list h3 {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1rem;
  color: #17110A;
}

.page-about .principles-list p {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.8;
  color: rgba(26, 18, 10, 0.82);
}

/* ---------- 结尾 ---------- */
.page-about .about-outro {
  margin-top: clamp(32px, 5vw, 60px);
  padding: clamp(26px, 4vw, 46px) 0 0;
  border-top: 1px solid var(--about-line);
}

.page-about .outro-inner {
  position: relative;
}

.page-about .outro-title {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.4rem, 3.4vw, 2.1rem);
  line-height: 1.2;
  color: var(--fog);
}

.page-about .outro-text {
  max-width: 52ch;
  margin: 0 0 22px;
  font-size: 0.94rem;
  line-height: 1.85;
  color: var(--about-text);
}

.page-about .outro-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

/* ---------- 中等屏 ---------- */
@media (min-width: 700px) {
  .page-about .hero-grid {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 0.85fr);
    align-items: end;
    gap: 40px;
  }

  .page-about .team-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    align-items: start;
  }

  .page-about .team-card:nth-child(2) {
    margin-top: 18px;
  }

  .page-about .team-card:nth-child(3) {
    margin-top: 36px;
  }

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

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

  .page-about .principles-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 24px;
  }

  .page-about .timeline {
    grid-auto-columns: 44%;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 1000px) {
  .page-about .about-body {
    grid-template-columns: 196px minmax(0, 1fr);
    gap: 52px;
    align-items: start;
  }

  .page-about .about-index {
    position: sticky;
    top: calc(var(--header-h) + 28px);
  }

  .page-about .index-title {
    display: block;
  }

  .page-about .index-list {
    flex-direction: column;
    gap: 4px;
    padding: 0;
    overflow: visible;
  }

  .page-about .index-list a {
    width: 100%;
    padding: 9px 12px;
    border-color: transparent;
    border-radius: var(--radius-md);
    background: transparent;
  }

  .page-about .index-list a:hover,
  .page-about .index-list a:focus-visible {
    border-color: rgba(55, 245, 228, 0.4);
  }

  .page-about .timeline {
    grid-auto-flow: row;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    grid-auto-columns: auto;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .fact-list li {
    grid-template-columns: 76px minmax(0, 1fr);
    padding: 16px 20px;
  }
}
</main>