.page-about {
  background: var(--navy);
  color: var(--light);
  overflow-x: hidden;
  line-height: 1.7;
}

.page-about *,
.page-about *::before,
.page-about *::after {
  box-sizing: border-box;
}

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

.page-about h1,
.page-about h2,
.page-about h3 {
  font-family: 'PingFang SC', 'Microsoft YaHei', 'Arial Black', sans-serif;
  font-weight: 800;
  line-height: 1.2;
  margin: 0;
}

.page-about p {
  margin: 0 0 1rem;
}

.page-about img {
  max-width: 100%;
  height: auto;
  border-radius: var(--radius);
}

/* 面包屑 */
.about-breadcrumb {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1rem 1.5rem 0;
  font-size: 0.8rem;
  color: var(--muted);
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.about-breadcrumb a {
  color: var(--cyan);
  text-decoration: none;
}

.about-breadcrumb a:hover {
  color: var(--gold);
}

.about-breadcrumb-sep {
  color: var(--muted);
}

.about-breadcrumb-current {
  color: var(--gold);
  font-weight: 600;
}

/* 首屏 Hero */
.about-hero {
  padding: 3.5rem 1.5rem 3rem;
  background: linear-gradient(135deg, var(--navy) 0%, var(--teal) 100%);
  position: relative;
}

.about-hero::after {
  content: "";
  position: absolute;
  right: -10%;
  top: 10%;
  width: 45%;
  height: 80%;
  background: radial-gradient(circle, rgba(77, 208, 225, 0.15) 0%, transparent 70%);
  pointer-events: none;
}

.about-hero-grid {
  max-width: var(--max-width);
  margin: 0 auto;
  display: grid;
  gap: 2.5rem;
  align-items: center;
}

.about-hero-tag {
  display: inline-block;
  padding: 0.3rem 1rem;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--gold);
  border: 1px solid var(--gold);
  border-radius: 999px;
  margin-bottom: 1.25rem;
}

.about-hero h1 {
  font-size: clamp(2.2rem, 5vw, 3.6rem);
  margin-bottom: 1.25rem;
}

.about-hero-lead {
  font-size: 1rem;
  color: var(--muted);
  max-width: 38rem;
  margin-bottom: 2rem;
}

.about-hero-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 2rem;
}

.about-hero-stat {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.about-hero-stat-num {
  font-family: 'Roboto Mono', 'SF Mono', monospace;
  font-size: 1.9rem;
  font-weight: 700;
  color: var(--gold);
}

.about-hero-stat-label {
  font-size: 0.78rem;
  color: var(--muted);
  letter-spacing: 0.06em;
}

/* 印章 */
.about-hero-seal {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 1rem;
}

.about-seal-svg {
  width: min(200px, 60vw);
  height: auto;
  animation: about-seal-breathe 4s ease-in-out infinite;
}

@keyframes about-seal-breathe {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.03); }
}

.about-hero-seal-caption {
  font-size: 0.8rem;
  color: var(--muted);
  letter-spacing: 0.14em;
  text-align: center;
}

/* 章节通用 */
.about-section-index {
  font-family: 'Roboto Mono', 'SF Mono', monospace;
  font-size: 1rem;
  font-weight: 700;
  color: var(--red);
  letter-spacing: 0.1em;
  margin-bottom: 0.35rem;
}

.about-section-label {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--gold);
  text-transform: uppercase;
  margin-bottom: 0.4rem;
}

/* 01 品牌起点 */
.about-origin {
  padding: 4rem 1.5rem;
  background: var(--teal);
}

.about-origin-grid {
  max-width: var(--max-width);
  margin: 0 auto;
  display: grid;
  gap: 2.5rem;
  align-items: center;
}

.about-origin h2 {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  margin-bottom: 1.25rem;
}

.about-origin p {
  color: var(--light);
  opacity: 0.9;
}

.about-origin-quote {
  margin: 1.5rem 0 0;
  padding: 1rem 1.25rem;
  border-left: 4px solid var(--gold);
  background: var(--glass);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-size: 1rem;
  color: var(--gold);
  font-weight: 600;
}

.about-origin-visual {
  position: relative;
}

.about-origin-img {
  width: 100%;
  height: auto;
  object-fit: cover;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.4);
}

/* 02 核心能力 */
.about-capability {
  padding: 4rem 1.5rem;
  background: var(--navy);
}

.about-capability-inner {
  max-width: var(--max-width);
  margin: 0 auto;
}

.about-section-header {
  margin-bottom: 2.5rem;
}

.about-section-header h2 {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  margin-bottom: 0.75rem;
}

.about-section-desc {
  color: var(--muted);
  max-width: 42rem;
}

.about-capability-stats {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem;
  margin-bottom: 3rem;
}

.about-stat-card {
  background: var(--glass);
  border-radius: var(--radius);
  padding: 1.75rem 1.5rem;
  border-top: 3px solid var(--gold);
  transition: transform var(--transition), background var(--transition);
}

.about-stat-card:hover {
  transform: translateY(-4px);
  background: rgba(255, 255, 255, 0.12);
}

.about-stat-num {
  display: block;
  font-family: 'Roboto Mono', 'SF Mono', monospace;
  font-size: 2.6rem;
  font-weight: 700;
  color: var(--gold);
  line-height: 1;
  margin-bottom: 0.5rem;
}

.about-stat-label {
  display: block;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--light);
  margin-bottom: 0.5rem;
  letter-spacing: 0.04em;
}

.about-stat-desc {
  font-size: 0.85rem;
  color: var(--muted);
  margin: 0;
}

/* 认证块 */
.about-cert-block {
  display: grid;
  gap: 2rem;
  align-items: center;
  background: rgba(255, 255, 255, 0.04);
  border-radius: var(--radius);
  padding: 2rem 1.5rem;
}

.about-cert-badge {
  display: flex;
  justify-content: center;
}

.about-cert-img {
  width: 100%;
  max-width: 240px;
  height: auto;
  border-radius: 50%;
  border: 2px solid rgba(212, 175, 55, 0.5);
  object-fit: cover;
}

.about-cert-copy h3 {
  font-size: 1.35rem;
  color: var(--gold);
  margin-bottom: 0.75rem;
}

.about-cert-copy p {
  color: var(--light);
  opacity: 0.9;
}

.about-cert-note {
  font-size: 0.85rem;
  color: var(--muted);
}

/* 03 发展脉络 */
.about-evolution {
  padding: 4rem 1.5rem;
  background: linear-gradient(160deg, var(--wine) 0%, var(--navy) 100%);
}

.about-evolution-inner {
  max-width: var(--max-width);
  margin: 0 auto;
}

.about-timeline {
  list-style: none;
  margin: 0;
  padding: 1rem 0 0;
  position: relative;
}

.about-timeline::before {
  content: "";
  position: absolute;
  left: 0.6rem;
  top: 0;
  bottom: 0;
  width: 3px;
  background: linear-gradient(to bottom, var(--gold), var(--red));
  border-radius: 999px;
}

.about-timeline-item {
  position: relative;
  padding: 0 0 2.5rem 2.5rem;
}

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

.about-timeline-marker {
  position: absolute;
  left: -0.75rem;
  top: 0;
  width: 2.7rem;
  height: 2.7rem;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: 'Roboto Mono', 'SF Mono', monospace;
  font-size: 0.68rem;
  font-weight: 700;
  color: var(--navy);
  background: var(--gold);
  box-shadow: 0 0 0 4px rgba(212, 175, 55, 0.2);
  z-index: 1;
  text-align: center;
  line-height: 1;
  padding: 0 0.2rem;
}

.about-timeline-card {
  background: var(--glass);
  border-radius: var(--radius);
  padding: 1.5rem;
  transition: background var(--transition), transform var(--transition);
}

.about-timeline-card:hover {
  background: rgba(255, 255, 255, 0.12);
  transform: translateX(4px);
}

.about-timeline-card h3 {
  font-size: 1.2rem;
  color: var(--gold);
  margin-bottom: 0.6rem;
}

.about-timeline-card p {
  font-size: 0.92rem;
  color: var(--light);
  opacity: 0.88;
  margin-bottom: 0.5rem;
}

.about-timeline-more {
  margin-top: 1rem;
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: var(--radius-sm);
  padding: 0.5rem 0.75rem;
  background: rgba(0, 0, 0, 0.2);
}

.about-timeline-more summary {
  cursor: pointer;
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--cyan);
  list-style: none;
  position: relative;
  padding-left: 1.4rem;
}

.about-timeline-more summary::before {
  content: "+";
  position: absolute;
  left: 0;
  top: -0.1rem;
  font-family: 'Roboto Mono', 'SF Mono', monospace;
  font-size: 1.1rem;
  color: var(--gold);
}

.about-timeline-more[open] summary::before {
  content: "–";
}

.about-timeline-more ul {
  margin: 0.75rem 0 0;
  padding-left: 1.2rem;
  font-size: 0.85rem;
  color: var(--light);
  opacity: 0.85;
}

.about-timeline-more li {
  margin-bottom: 0.35rem;
}

/* 04 数据合作与生态伙伴 */
.about-ecosystem {
  padding: 4rem 1.5rem;
  background: var(--teal);
}

.about-ecosystem-grid {
  max-width: var(--max-width);
  margin: 0 auto;
  display: grid;
  gap: 2.5rem;
  align-items: center;
}

.about-ecosystem h2 {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  margin-bottom: 1rem;
}

.about-ecosystem p {
  color: var(--light);
  opacity: 0.9;
}

.about-ecosystem-list {
  margin: 1.25rem 0;
  padding-left: 1.25rem;
  color: var(--light);
  opacity: 0.9;
  font-size: 0.92rem;
}

.about-ecosystem-list li {
  margin-bottom: 0.6rem;
}

.about-ecosystem-visual img {
  width: 100%;
  height: auto;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.4);
}

/* 05 治理与合规 */
.about-compliance {
  padding: 4rem 1.5rem;
  background: var(--navy);
}

.about-compliance-card {
  max-width: var(--max-width);
  margin: 0 auto;
  background: var(--glass);
  border-radius: var(--radius);
  padding: 2.5rem 1.75rem;
  border-left: 4px solid var(--gold);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.3);
}

.about-compliance h2 {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  margin-bottom: 1rem;
}

.about-compliance-lead {
  font-size: 1.1rem;
  color: var(--light);
  font-weight: 600;
  opacity: 0.95;
}

.about-compliance-list {
  margin: 1.25rem 0;
  padding-left: 1.25rem;
  color: var(--light);
  opacity: 0.88;
  font-size: 0.92rem;
}

.about-compliance-list li {
  margin-bottom: 0.6rem;
}

.about-compliance-trust {
  font-size: 0.85rem;
  color: var(--muted);
  margin-top: 1rem;
  border-top: 1px solid rgba(255, 255, 255, 0.15);
  padding-top: 1rem;
}

/* 06 CTA */
.about-cta {
  padding: 4rem 1.5rem;
  background: linear-gradient(135deg, var(--wine) 0%, #4a0d18 100%);
}

.about-cta-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  text-align: center;
}

.about-cta h2 {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  margin-bottom: 0.75rem;
}

.about-cta p {
  color: var(--light);
  opacity: 0.85;
  max-width: 36rem;
  margin: 0 auto 2rem;
}

.about-cta-links {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: center;
}

/* ========== 桌面端 ========== */
@media (min-width: 768px) {
  .about-hero {
    padding: 5rem 2rem 4rem;
  }

  .about-hero-grid {
    grid-template-columns: 1.1fr 0.9fr;
    gap: 4rem;
  }

  .about-origin {
    padding: 5.5rem 2rem;
  }

  .about-origin-grid {
    grid-template-columns: 1.1fr 0.9fr;
    gap: 4rem;
  }

  .about-capability {
    padding: 5.5rem 2rem;
  }

  .about-capability-stats {
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
  }

  .about-cert-block {
    grid-template-columns: 0.7fr 1.3fr;
    padding: 3rem;
  }

  .about-evolution {
    padding: 5.5rem 2rem;
  }

  .about-timeline {
    padding: 1rem 0 0;
  }

  .about-timeline::before {
    left: 50%;
    margin-left: -1.5px;
  }

  .about-timeline-item {
    width: 50%;
    padding: 0 0 3.5rem 0;
  }

  .about-timeline-item:nth-child(odd) {
    padding-right: 3.5rem;
  }

  .about-timeline-item:nth-child(even) {
    margin-left: 50%;
    padding-left: 3.5rem;
  }

  .about-timeline-marker {
    left: auto;
    right: -1.35rem;
    width: 2.9rem;
    height: 2.9rem;
    font-size: 0.78rem;
  }

  .about-timeline-item:nth-child(even) .about-timeline-marker {
    left: -1.35rem;
    right: auto;
  }

  .about-timeline-card {
    padding: 1.75rem;
  }

  .about-ecosystem {
    padding: 5.5rem 2rem;
  }

  .about-ecosystem-grid {
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
  }

  .about-compliance {
    padding: 5.5rem 2rem;
  }

  .about-compliance-card {
    padding: 3.5rem 3rem;
  }

  .about-cta {
    padding: 5rem 2rem;
  }

  .about-cta-links {
    gap: 1.25rem;
  }
}

@media (min-width: 1024px) {
  .about-capability-stats {
    grid-template-columns: repeat(4, 1fr);
  }

  .about-security-grid {
    grid-template-columns: 1fr 1fr;
  }

  .about-hero-grid {
    grid-template-columns: 1.2fr 0.8fr;
  }

  .about-stat-num {
    font-size: 3rem;
  }
}