.page-about {
  --about-card-bg: rgba(15, 42, 82, 0.72);
  --about-card-line: rgba(232, 237, 242, 0.12);
  --about-gold-soft: rgba(212, 175, 55, 0.18);
  --about-grid-light: rgba(232, 237, 242, 0.05);
  --about-deep-text: #16233A;
  color: var(--color-dark);
}

/* ========== Hero ========== */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: 52px 0 64px;
  background:
    linear-gradient(rgba(11, 27, 58, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(11, 27, 58, 0.05) 1px, transparent 1px),
    var(--color-bg);
  background-size: 34px 34px;
}
.page-about .about-hero::after {
  content: "";
  position: absolute;
  top: -80px;
  right: -80px;
  width: 340px;
  height: 340px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(212, 175, 55, 0.18), transparent 68%);
  pointer-events: none;
}
.page-about .about-hero .breadcrumbs {
  margin-bottom: 36px;
}
.page-about .about-hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 32px;
  align-items: center;
}
.page-about .about-hero .eyebrow {
  color: var(--color-deep-space);
}
.page-about .about-hero h1 {
  margin-top: 14px;
  font-size: clamp(2rem, 5vw, 3.2rem);
  line-height: 1.14;
  font-weight: 900;
  letter-spacing: -0.02em;
  color: var(--color-deep-space);
}
.page-about .about-hero-lead {
  margin-top: 20px;
  max-width: 620px;
  font-size: 1.04rem;
  line-height: 1.8;
  color: var(--about-deep-text);
}
.page-about .about-hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 16px 32px;
  margin-top: 28px;
}
.page-about .about-hero-meta-item {
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.page-about .meta-label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  color: var(--color-muted);
}
.page-about .meta-label::before {
  content: "▹ ";
  color: var(--color-gold);
}
.page-about .about-hero-meta-item strong {
  font-family: var(--font-mono);
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--color-deep-space);
}
.page-about .about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 32px;
}
.page-about .about-hero-visual {
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  background: var(--color-deep-space);
}
.page-about .about-hero-img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* ========== 时间轴 ========== */
.page-about .about-milestones {
  position: relative;
  overflow: hidden;
  padding: 72px 0 80px;
  color: var(--color-light);
  background:
    linear-gradient(var(--about-grid-light) 1px, transparent 1px),
    linear-gradient(90deg, var(--about-grid-light) 1px, transparent 1px),
    var(--color-deep-space);
  background-size: 44px 44px;
}
.page-about .about-milestones::after {
  content: "";
  position: absolute;
  right: -200px;
  bottom: -160px;
  width: 480px;
  height: 480px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(241, 208, 122, 0.08), transparent 70%);
  pointer-events: none;
}
.page-about .about-milestones .content-shell {
  position: relative;
  z-index: 1;
}
.page-about .section-head {
  max-width: 760px;
  margin-bottom: 40px;
}
.page-about .section-head h2 {
  margin-top: 10px;
  font-size: clamp(1.7rem, 3.4vw, 2.5rem);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.01em;
  color: var(--color-deep-space);
}
.page-about .section-head--light h2 {
  color: var(--color-light);
}
.page-about .section-head .eyebrow {
  color: var(--color-deep-space);
}
.page-about .section-head--light .eyebrow {
  color: var(--color-gold);
}
.page-about .section-lead {
  margin-top: 12px;
  font-size: 1rem;
  line-height: 1.75;
  color: var(--color-muted);
}
.page-about .section-head--light .section-lead {
  color: rgba(232, 237, 242, 0.62);
}
.page-about .about-timeline {
  position: relative;
  display: grid;
  gap: 28px;
  margin-top: 48px;
}
.page-about .about-timeline::before {
  content: "";
  position: absolute;
  top: 10px;
  bottom: 10px;
  left: 72px;
  width: 1px;
  background: linear-gradient(to bottom, rgba(212, 175, 55, 0.2), rgba(241, 208, 122, 0.8) 50%, rgba(212, 175, 55, 0.2));
}
.page-about .timeline-svg {
  position: absolute;
  left: 0;
  top: 0;
  width: 220px;
  height: 100%;
  pointer-events: none;
  opacity: 0.9;
  z-index: 0;
}
.page-about .timeline-item {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 72px 1fr;
  gap: 20px;
  align-items: start;
  --tl-shift: 0px;
}
.page-about .timeline-mark {
  position: relative;
}
.page-about .timeline-year {
  display: block;
  text-align: right;
  padding-right: 22px;
  font-family: var(--font-mono);
  font-size: 0.92rem;
  font-weight: 700;
  line-height: 1.4;
  color: var(--color-gold);
}
.page-about .timeline-dot {
  position: absolute;
  right: -6px;
  top: 16px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--color-gold-end);
  box-shadow: 0 0 0 5px var(--about-gold-soft), 0 0 16px rgba(212, 175, 55, 0.5);
}
.page-about .timeline-card {
  background: var(--about-card-bg);
  border: 1px solid var(--about-card-line);
  border-radius: var(--radius);
  padding: 22px 20px 20px;
  transform: translateX(var(--tl-shift));
  transition:
    border-color 0.3s var(--ease),
    box-shadow 0.3s var(--ease),
    transform 0.3s var(--ease),
    background 0.3s var(--ease);
}
.page-about .timeline-item:hover .timeline-card,
.page-about .timeline-item:focus-within .timeline-card {
  border-color: rgba(212, 175, 55, 0.5);
  background: rgba(15, 42, 82, 0.86);
  box-shadow: 0 12px 28px rgba(0, 0, 0, 0.24);
  transform: translateX(var(--tl-shift)) translateY(-2px);
}
.page-about .timeline-tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  color: var(--color-gold-end);
  border: 1px solid rgba(212, 175, 55, 0.4);
  border-radius: 999px;
  padding: 2px 10px;
  margin-bottom: 12px;
}
.page-about .timeline-card h3 {
  font-size: 1.12rem;
  font-weight: 700;
  color: var(--color-light);
  line-height: 1.4;
}
.page-about .timeline-card p {
  margin-top: 8px;
  font-size: 0.92rem;
  line-height: 1.75;
  color: rgba(232, 237, 242, 0.72);
}
.page-about .timeline-link {
  color: var(--color-gold-end);
  text-decoration: underline;
  text-underline-offset: 2px;
}

@media (max-width: 767px) {
  .page-about .timeline-svg {
    display: none;
  }
}

/* ========== 服务规模 ========== */
.page-about .about-scale {
  padding: 72px 0 80px;
  background: #ffffff;
}
.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
  margin-top: 40px;
}
.page-about .about-stat {
  padding: 22px 18px;
  border: 1px solid var(--color-line-light);
  border-radius: var(--radius);
  background: var(--color-bg);
  transition:
    border-color 0.3s var(--ease),
    box-shadow 0.3s var(--ease),
    transform 0.3s var(--ease);
}
.page-about .about-stat:hover {
  border-color: rgba(212, 175, 55, 0.6);
  box-shadow: var(--shadow-sm);
  transform: translateY(-2px);
}
.page-about .stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.7rem, 4vw, 2.5rem);
  font-weight: 700;
  line-height: 1.1;
  color: var(--color-deep-space);
}
.page-about .stat-label {
  display: block;
  margin-top: 8px;
  font-size: 0.88rem;
  color: var(--color-muted);
}
.page-about .about-scale-chart {
  display: grid;
  gap: 28px;
  margin-top: 48px;
  align-items: center;
}
.page-about .about-chart-copy h3 {
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--color-deep-space);
}
.page-about .about-chart-copy p {
  margin-top: 10px;
  color: var(--about-deep-text);
  line-height: 1.8;
}
.page-about .about-chart-visual {
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  background: var(--color-bg);
}
.page-about .about-chart-img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* ========== 团队 ========== */
.page-about .about-team {
  padding: 72px 0 80px;
  background: linear-gradient(150deg, var(--color-aux-space) 0%, var(--color-deep-space) 100%);
  color: var(--color-light);
}
.page-about .about-team-grid {
  display: grid;
  gap: 20px;
  margin-top: 40px;
}
.page-about .team-card {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(232, 237, 242, 0.1);
  border-radius: var(--radius);
  padding: 26px 24px 28px;
  transition:
    border-color 0.3s var(--ease),
    background 0.3s var(--ease),
    transform 0.3s var(--ease),
    box-shadow 0.3s var(--ease);
}
.page-about .team-card:hover,
.page-about .team-card:focus-within {
  border-color: rgba(212, 175, 55, 0.45);
  background: rgba(255, 255, 255, 0.07);
  box-shadow: 0 12px 28px rgba(0, 0, 0, 0.18);
  transform: translateY(-2px);
}
.page-about .team-count {
  display: block;
  font-family: var(--font-mono);
  font-size: 2.8rem;
  font-weight: 700;
  line-height: 1;
  color: var(--color-gold);
}
.page-about .team-unit {
  font-size: 1rem;
  font-weight: 500;
  color: var(--color-gold-end);
  margin-left: 4px;
}
.page-about .team-card h3 {
  margin-top: 16px;
  font-size: 1.18rem;
  font-weight: 700;
  color: var(--color-light);
}
.page-about .team-card p {
  margin-top: 10px;
  font-size: 0.93rem;
  line-height: 1.75;
  color: rgba(232, 237, 242, 0.7);
}

/* ========== 资质 ========== */
.page-about .about-cert {
  padding: 72px 0 80px;
  background: var(--color-bg);
}
.page-about .about-cert-grid {
  display: grid;
  gap: 28px;
  margin-top: 40px;
}
.page-about .cert-visual {
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  background: #ffffff;
}
.page-about .cert-img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}
.page-about .image-caption {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding: 12px 16px;
  border-top: 1px solid var(--color-line-light);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--color-muted);
}
.page-about .cert-list {
  display: grid;
  gap: 12px;
  align-content: center;
}
.page-about .cert-item {
  background: #ffffff;
  border: 1px solid var(--color-line-light);
  border-radius: var(--radius);
  padding: 18px 20px;
  transition:
    border-color 0.3s var(--ease),
    box-shadow 0.3s var(--ease);
}
.page-about .cert-item:hover,
.page-about .cert-item:focus-within {
  border-color: rgba(212, 175, 55, 0.5);
  box-shadow: var(--shadow-sm);
}
.page-about .cert-item summary {
  cursor: pointer;
  font-weight: 700;
  color: var(--color-dark);
  list-style: none;
  display: flex;
  align-items: center;
  gap: 12px;
}
.page-about .cert-item summary::-webkit-details-marker {
  display: none;
}
.page-about .cert-item summary::before {
  content: "+";
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--color-deep-space);
  color: var(--color-gold);
  font-family: var(--font-mono);
  font-size: 0.9rem;
  line-height: 1;
  flex-shrink: 0;
  transition: transform 0.3s var(--ease);
}
.page-about .cert-item[open] summary::before {
  transform: rotate(45deg);
}
.page-about .cert-item p {
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px solid var(--color-line-light);
  color: var(--color-muted);
  font-size: 0.92rem;
  line-height: 1.7;
}

/* ========== 合作与生态 ========== */
.page-about .about-ecosystem {
  padding: 72px 0 80px;
  background: #ffffff;
}
.page-about .about-eco-list {
  margin-top: 40px;
  display: grid;
}
.page-about .eco-item {
  display: grid;
  gap: 6px;
  padding: 22px 4px;
  border-bottom: 1px solid var(--color-line-light);
}
.page-about .eco-item:first-child {
  border-top: 1px solid var(--color-line-light);
}
.page-about .eco-item dt {
  font-weight: 800;
  font-size: 1.05rem;
  color: var(--color-deep-space);
}
.page-about .eco-item dt::before {
  content: "◆";
  color: var(--color-gold);
  font-size: 0.72rem;
  margin-right: 8px;
  vertical-align: 2px;
}
.page-about .eco-item dd {
  margin: 0;
  font-size: 0.95rem;
  line-height: 1.75;
  color: var(--about-deep-text);
}
.page-about .eco-item a {
  color: var(--color-deep-space);
  font-weight: 600;
  text-decoration: underline;
  text-underline-offset: 2px;
  text-decoration-color: rgba(212, 175, 55, 0.55);
}

/* ========== 底部连接区 ========== */
.page-about .about-connect {
  padding: 72px 0 88px;
  background: var(--color-bg);
}
.page-about .about-connect-panel {
  position: relative;
  overflow: hidden;
  padding: 40px 28px 36px;
  border-radius: var(--radius);
  background: #ffffff;
  box-shadow: var(--shadow-sm);
}
.page-about .about-connect-panel::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--color-gold), var(--color-gold-end), var(--color-vivid-orange));
}
.page-about .about-connect .eyebrow {
  color: var(--color-deep-space);
}
.page-about .about-connect-copy h2 {
  margin-top: 10px;
  font-size: clamp(1.5rem, 3vw, 2.1rem);
  font-weight: 800;
  line-height: 1.3;
  color: var(--color-deep-space);
}
.page-about .about-connect-copy p {
  margin-top: 14px;
  color: var(--color-muted);
  line-height: 1.75;
  font-size: 0.95rem;
}
.page-about .about-connect-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

/* ========== 桌面端增强 ========== */
@media (min-width: 768px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, 1fr);
    gap: 18px;
  }
  .page-about .about-team-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
  }
  .page-about .about-scale-chart {
    grid-template-columns: 1fr 1.3fr;
    gap: 40px;
  }
  .page-about .about-cert-grid {
    grid-template-columns: 0.9fr 1.1fr;
    gap: 40px;
  }
  .page-about .about-connect-panel {
    padding: 48px 44px;
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 28px;
    align-items: center;
  }
  .page-about .about-connect-links {
    margin-top: 0;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding: 72px 0 88px;
  }
  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 6fr);
    gap: 56px;
  }
  .page-about .about-timeline {
    gap: 40px;
  }
  .page-about .timeline-item {
    grid-template-columns: 160px 1fr;
    gap: 32px;
  }
  .page-about .about-timeline::before {
    left: 160px;
  }
  .page-about .timeline-year {
    font-size: 1.05rem;
  }
  .page-about .timeline-card {
    padding: 26px 28px 24px;
  }
  .page-about .timeline-item:nth-of-type(2) {
    --tl-shift: 24px;
  }
  .page-about .timeline-item:nth-of-type(3) {
    --tl-shift: 48px;
  }
  .page-about .timeline-item:nth-of-type(4) {
    --tl-shift: 72px;
  }
}