.page-about {
  background: var(--c-bg);
  color: var(--c-ink);
  font-family: var(--font-sans);
}

.page-about .about-wrap {
  overflow: clip;
}

.page-about .about-section {
  padding: 56px 0;
  scroll-margin-top: calc(var(--header-h) + 16px);
}

.page-about .about-section h2 {
  font-size: 32px;
  font-weight: 900;
  line-height: 1.25;
  letter-spacing: -0.02em;
  color: var(--c-primary);
  margin: 8px 0 16px;
}

.page-about .about-section h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--c-ink);
  margin: 0 0 8px;
}

.page-about .about-section p {
  line-height: 1.8;
  color: var(--c-ink);
  margin: 0 0 12px;
}

.page-about .mono-label {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--c-muted);
  margin: 0 0 8px;
}

.page-about .stat-num {
  font-family: var(--font-mono);
  font-size: 46px;
  font-weight: 800;
  line-height: 1;
  color: var(--c-primary);
  display: flex;
  align-items: baseline;
  gap: 2px;
  color: var(--c-primary);
}

.page-about .stat-unit {
  font-size: 16px;
  font-weight: 500;
  margin-left: 2px;
  color: var(--c-muted);
}

/* 01 品牌故事 */
.page-about .story {
  background: var(--c-bg);
}

.page-about .story-grid {
  display: grid;
  gap: 36px;
}

.page-about .story-lead {
  font-size: 19px;
  font-weight: 700;
  line-height: 1.75;
  color: var(--c-primary);
  margin-bottom: 14px;
}

.page-about .story-text p:last-of-type {
  margin-bottom: 0;
}

.page-about .story-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 20px 40px;
  margin-top: 28px;
  padding-top: 22px;
  border-top: 1px solid var(--c-line);
}

.page-about .story-meta-num {
  font-family: var(--font-mono);
  font-size: 24px;
  font-weight: 700;
  color: var(--c-warm);
  margin: 0;
}

.page-about .story-media img,
.page-about .system-media img,
.page-about .milestone-media img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: var(--radius-l);
  box-shadow: var(--shadow-m);
  transition: transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .story-media img:hover,
.page-about .system-media img:hover,
.page-about .milestone-media img:hover {
  transform: scale(1.005);
  box-shadow: 0 10px 32px rgba(6, 18, 43, 0.18);
}

/* 02 数据体系 */
.page-about .system {
  background: #FFFFFF;
}

.page-about .system-intro {
  max-width: 720px;
}

.page-about .system-grid {
  display: grid;
  gap: 16px;
  margin-top: 28px;
}

.page-about .system-item {
  border: 1px solid var(--c-line);
  border-radius: var(--radius-m);
  background: var(--c-bg);
  padding: 22px 22px;
  transition: border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .system-item:hover {
  border-color: var(--c-accent);
  box-shadow: var(--shadow-m);
  transform: translateY(-2px);
}

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

.page-about .system-media {
  margin-top: 24px;
}

/* 03 技术架构 */
.page-about .arch {
  background: linear-gradient(160deg, var(--c-primary-deep) 0%, var(--c-primary) 100%);
  color: #FFFFFF;
}

.page-about .arch h2 {
  color: #FFFFFF;
}

.page-about .arch p {
  color: rgba(255, 255, 255, 0.82);
}

.page-about .arch .arch-intro {
  max-width: 720px;
}

.page-about .arch .mono-label {
  color: rgba(255, 255, 255, 0.56);
}

.page-about .arch .section-index--dark {
  color: var(--c-accent);
}

.page-about .arch-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-top: 32px;
}

.page-about .arch-stat {
  border: 1px solid rgba(255, 255, 255, 0.14);
  background: rgba(255, 255, 255, 0.04);
  border-radius: var(--radius-m);
  padding: 18px 16px;
  min-height: 100px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .arch-stat:hover {
  background: rgba(0, 255, 136, 0.08);
  border-color: var(--c-accent);
}

.page-about .arch-stat .stat-num {
  color: var(--c-accent);
  font-size: 38px;
}

.page-about .arch-stat .stat-unit {
  color: rgba(255, 255, 255, 0.62);
}

.page-about .arch-stat .stat-label {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.72);
  margin-top: 8px;
  line-height: 1.5;
  margin-bottom: 0;
}

.page-about .arch-layers {
  margin-top: 28px;
  display: grid;
  gap: 10px;
}

.page-about .layer-item {
  border-left: 2px solid var(--c-accent);
  background: rgba(255, 255, 255, 0.03);
  padding: 16px 18px;
  border-radius: 0 var(--radius-s) var(--radius-s) 0;
  transition: background var(--dur) var(--ease);
}

.page-about .layer-item:hover {
  background: rgba(0, 255, 136, 0.09);
}

.page-about .layer-order {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 700;
  color: var(--c-accent);
  letter-spacing: 0.1em;
  margin: 0;
}

.page-about .layer-item h3 {
  color: #FFFFFF;
  margin-top: 6px;
}

.page-about .layer-item p:last-child {
  font-size: 14px;
  margin-bottom: 0;
}

/* 04 发展里程碑 */
.page-about .milestone {
  background: var(--c-bg);
}

.page-about .timeline {
  margin-top: 32px;
  border-left: 1px solid var(--c-line);
  padding-left: 24px;
}

.page-about .timeline-item {
  position: relative;
  padding-bottom: 32px;
}

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

.page-about .timeline-item::before {
  content: "";
  position: absolute;
  left: -31px;
  top: 8px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--c-bg);
  border: 3px solid var(--c-accent);
}

.page-about .timeline-year {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--c-warm);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin: 0 0 8px;
}

.page-about .timeline-content {
  background: #FFFFFF;
  border: 1px solid var(--c-line);
  border-radius: var(--radius-m);
  padding: 18px 20px;
  box-shadow: var(--shadow-s);
  transition: border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .timeline-content:hover {
  border-color: var(--c-accent);
  box-shadow: var(--shadow-m);
}

.page-about .timeline-content h3 {
  font-size: 17px;
  margin-bottom: 6px;
}

.page-about .timeline-content p {
  font-size: 15px;
  line-height: 1.75;
  margin: 0;
}

.page-about .milestone-media {
  margin-top: 28px;
}

/* 05 团队与生态 */
.page-about .team {
  background: #FFFFFF;
}

.page-about .team-grid {
  display: grid;
  gap: 16px;
  margin-top: 28px;
}

.page-about .team-card {
  border: 1px solid var(--c-line);
  border-radius: var(--radius-m);
  background: var(--c-bg);
  padding: 26px 22px;
  transition: border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .team-card:hover {
  border-color: var(--c-warm);
  box-shadow: var(--shadow-m);
}

.page-about .team-card .stat-num {
  font-size: 40px;
  margin-bottom: 10px;
  color: var(--c-primary);
}

.page-about .team-card .stat-unit {
  color: var(--c-muted);
}

.page-about .team-card h3 {
  margin-bottom: 8px;
}

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

.page-about .team-badges {
  display: grid;
  gap: 10px;
  margin-top: 22px;
}

.page-about .badge-item {
  border: 1px solid var(--c-line);
  background: var(--c-orange-tint);
  border-radius: var(--radius-s);
  padding: 14px 16px;
}

.page-about .badge-item p {
  font-size: 15px;
  font-weight: 600;
  color: var(--c-ink);
  margin: 0;
}

.page-about .badge-item .mono-label {
  color: var(--c-warm);
  margin-bottom: 4px;
}

/* 延伸入口 */
.page-about .out {
  background: linear-gradient(135deg, var(--c-primary-deep) 0%, var(--c-primary) 100%);
}

.page-about .out-box {
  padding: 20px 0;
  text-align: center;
}

.page-about .out-box h2 {
  color: #FFFFFF;
  font-size: 32px;
}

.page-about .out-box p:not(.section-index) {
  color: rgba(255, 255, 255, 0.82);
  max-width: 620px;
  margin-left: auto;
  margin-right: auto;
  margin-bottom: 22px;
}

.page-about .out-box .section-index--dark {
  color: var(--c-accent);
}

.page-about .out-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
}

/* ---------- 平板与桌面 ---------- */
@media (min-width: 768px) {
  .page-about .about-section {
    padding: 72px 0;
  }

  .page-about .about-section h2 {
    font-size: 36px;
  }

  .page-about .story-grid {
    grid-template-columns: 1.2fr 1fr;
    align-items: center;
    gap: 44px;
  }

  .page-about .story-meta {
    gap: 28px 48px;
  }

  .page-about .system-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 18px;
  }

  .page-about .arch-stats {
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
  }

  .page-about .arch-layers {
    grid-template-columns: 1fr 1fr;
    gap: 12px;
  }

  .page-about .team-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
  }

  .page-about .team-badges {
    grid-template-columns: 1fr 1fr;
    gap: 14px;
  }

  .page-about .timeline {
    padding-left: 40px;
  }

  .page-about .timeline-item::before {
    left: -47px;
  }
}

@media (min-width: 1024px) {
  .page-about .about-section {
    padding: 92px 0;
  }

  .page-about .about-section h2 {
    font-size: 40px;
    margin-top: 12px;
    margin-bottom: 20px;
  }

  .page-about .story-grid {
    grid-template-columns: 1.1fr 0.9fr;
    gap: 72px;
  }

  .page-about .story-lead {
    font-size: 21px;
  }

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

  .page-about .arch-stats {
    gap: 20px;
    margin-top: 40px;
  }

  .page-about .arch-stat .stat-num {
    font-size: 48px;
  }

  .page-about .arch-layers {
    gap: 16px;
    margin-top: 36px;
  }

  .page-about .layer-item {
    padding: 20px 22px;
  }

  .page-about .timeline {
    padding-left: 56px;
    max-width: 780px;
  }

  .page-about .timeline-item::before {
    left: -63px;
    width: 13px;
    height: 13px;
  }

  .page-about .timeline-content {
    padding: 22px 26px;
  }

  .page-about .team-grid {
    gap: 20px;
  }

  .page-about .team-badges {
    gap: 18px;
    margin-top: 28px;
  }

  .page-about .milestone-media {
    margin-top: 40px;
  }

  .page-about .out-box h2 {
    font-size: 36px;
  }
}