.page-about {
  --about-accent-soft: rgba(201, 160, 99, 0.2);
  --about-gold-glow: rgba(201, 160, 99, 0.32);
  --about-line-light: rgba(255, 255, 255, 0.09);
  --about-card-bg: rgba(248, 246, 241, 0.06);
  --about-mobile-pad: var(--space-lg) 0;
}

/* ===== 首屏英雄区 ===== */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  background: var(--color-primary);
  color: #ffffff;
  padding: var(--space-md) 0 var(--space-xl);
}

.page-about .hero-bg-grid {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
}

.page-about .hero-diamond {
  position: absolute;
  right: 36px;
  top: 120px;
  width: 56px;
  height: 56px;
  background: linear-gradient(135deg, var(--color-accent-light), var(--color-accent));
  opacity: 0.16;
  transform: rotate(45deg);
  pointer-events: none;
}

.page-about .breadcrumb {
  position: relative;
  z-index: 1;
}

.page-about .hero-layout {
  position: relative;
  z-index: 1;
  display: grid;
  gap: var(--space-lg);
  padding-top: var(--space-md);
}

.page-about .hero-copy h1 {
  margin: 12px 0 20px;
  font-family: var(--font-heading);
  font-size: var(--font-size-hero);
  font-weight: 700;
  line-height: 1.12;
  letter-spacing: -0.01em;
}

.page-about .hero-lead {
  max-width: 640px;
  margin: 0 0 28px;
  font-size: 16px;
  line-height: 1.75;
  color: rgba(255, 255, 255, 0.78);
}

.page-about .hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

.page-about .hero-actions .btn-ghost {
  color: #ffffff;
  border-color: rgba(255, 255, 255, 0.3);
  background: transparent;
}

.page-about .hero-actions .btn-ghost:hover {
  border-color: var(--color-accent);
  color: var(--color-accent-light);
}

.page-about .hero-fact-card {
  position: relative;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  padding: 24px 24px 16px;
  align-self: start;
}

.page-about .hero-fact-card::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 24px;
  right: 24px;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--color-accent), transparent);
}

.page-about .fact-index {
  display: block;
  margin-bottom: 12px;
  font-family: var(--font-body);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-accent-light);
}

.page-about .fact-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.07);
}

.page-about .fact-row:last-child {
  border-bottom: none;
}

.page-about .fact-row dt {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.62);
}

.page-about .fact-row dd {
  margin: 0;
  font-family: var(--font-heading);
  font-size: 18px;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  color: #ffffff;
}

/* ===== 发展脉络 ===== */
.page-about .about-timeline-section {
  position: relative;
  background: var(--color-bg);
  padding: var(--about-mobile-pad);
}

.page-about .timeline-texture {
  position: absolute;
  top: 0;
  right: 0;
  width: 60%;
  height: 100%;
  object-fit: cover;
  object-position: center;
  opacity: 0.07;
  pointer-events: none;
}

.page-about .section-desc {
  margin: 14px 0 0;
  max-width: 560px;
  color: var(--color-text-muted);
  font-size: 15px;
  line-height: 1.7;
}

.page-about .about-timeline {
  position: relative;
  margin: 44px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(180deg, var(--color-accent-light), var(--color-border) 85%);
}

.page-about .about-timeline .timeline-item {
  position: relative;
  padding-left: 34px;
  margin-bottom: var(--space-md);
}

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

.page-about .about-timeline .timeline-dot {
  position: absolute;
  left: 0;
  top: 6px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--color-accent);
  box-shadow: 0 0 0 5px var(--about-accent-soft);
}

.page-about .about-timeline .timeline-item[data-year]:not([data-year=""]) .timeline-dot {
  background: var(--color-accent-light);
  box-shadow: 0 0 0 5px var(--about-gold-glow);
}

.page-about .about-timeline details {
  border-bottom: 1px solid var(--color-border);
  padding: 4px 0 14px;
}

.page-about .about-timeline summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-heading);
  font-size: 21px;
  font-weight: 700;
  color: var(--color-text);
  line-height: 1.4;
  transition: color var(--transition-fast);
}

.page-about .about-timeline summary::-webkit-details-marker {
  display: none;
}

.page-about .about-timeline summary::before {
  content: "+";
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 22px;
  height: 22px;
  border: 1px solid var(--color-accent);
  border-radius: 50%;
  font-family: var(--font-body);
  font-size: 14px;
  font-weight: 500;
  color: var(--color-accent);
  flex-shrink: 0;
  line-height: 1;
  transition: transform var(--transition-fast), background var(--transition-fast), color var(--transition-fast);
}

.page-about .about-timeline details[open] summary::before {
  content: "−";
  background: var(--color-accent);
  color: #ffffff;
}

.page-about .about-timeline summary:hover {
  color: var(--color-accent);
}

.page-about .about-timeline details p {
  margin: 12px 0 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--color-text-muted);
  max-width: 620px;
}

/* ===== 核心数据 ===== */
.page-about .about-data-section {
  background: linear-gradient(180deg, var(--color-primary-deep), var(--color-primary) 60%);
  color: #ffffff;
  padding: var(--about-mobile-pad);
}

.page-about .about-data-section .eyebrow {
  color: var(--color-accent-light);
}

.page-about .about-data-section h2 {
  color: #ffffff;
}

.page-about .about-data-section .section-desc {
  color: rgba(255, 255, 255, 0.66);
}

.page-about .data-layout {
  display: grid;
  gap: var(--space-lg);
  margin-top: 32px;
}

.page-about .data-copy {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.page-about .data-chart {
  width: 100%;
  max-width: 460px;
  margin-top: 24px;
  border: 1px solid rgba(255, 255, 255, 0.1);
  object-fit: cover;
}

.page-about .data-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  align-content: start;
}

.page-about .data-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  background: var(--about-card-bg);
  border: 1px solid var(--about-line-light);
  border-left: 3px solid var(--color-accent);
  padding: 18px 20px;
  transition: transform var(--transition-fast), border-color var(--transition-fast), background var(--transition-fast);
}

.page-about .data-card:hover {
  transform: translateY(-3px);
  border-color: var(--color-accent);
  background: rgba(255, 255, 255, 0.09);
}

.page-about .data-info {
  display: flex;
  flex-direction: column;
  gap: 4px;
  min-width: 0;
}

.page-about .data-label {
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: rgba(255, 255, 255, 0.82);
}

.page-about .data-extra {
  font-size: 12px;
  line-height: 1.5;
  color: rgba(255, 255, 255, 0.5);
  opacity: 1;
  transition: opacity var(--transition-fast), max-height var(--transition-slow);
}

.page-about .data-value {
  font-family: var(--font-heading);
  font-size: 42px;
  font-weight: 700;
  line-height: 1;
  color: #ffffff;
  white-space: nowrap;
  font-variant-numeric: tabular-nums;
}

.page-about .data-value span {
  font-size: 0.48em;
  font-weight: 500;
  color: var(--color-accent-light);
  margin-left: 2px;
}

/* ===== 资质与荣誉 ===== */
.page-about .about-honor-section {
  background: var(--color-bg);
  padding: var(--about-mobile-pad);
}

.page-about .honor-layout {
  display: grid;
  gap: var(--space-lg);
  margin-top: 32px;
}

.page-about .honor-badge {
  width: 100%;
  max-width: 360px;
  height: auto;
  object-fit: cover;
  border: 1px solid var(--color-border);
  justify-self: start;
}

.page-about .honor-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 0;
}

.page-about .honor-card {
  display: flex;
  gap: 20px;
  align-items: flex-start;
  padding: 24px 0;
  border-bottom: 1px solid var(--color-border);
  transition: background var(--transition-fast), padding var(--transition-fast);
}

.page-about .honor-card:first-child {
  padding-top: 0;
}

.page-about .honor-card:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.page-about .honor-card:hover {
  padding-left: 8px;
  padding-right: 8px;
  background: rgba(11, 27, 58, 0.03);
}

.page-about .honor-index {
  font-family: var(--font-heading);
  font-size: 32px;
  font-weight: 700;
  color: var(--color-accent);
  line-height: 1;
  flex-shrink: 0;
  min-width: 42px;
}

.page-about .honor-body h3 {
  margin: 0 0 8px;
  font-family: var(--font-heading);
  font-size: 21px;
  font-weight: 700;
  color: var(--color-text);
  line-height: 1.4;
}

.page-about .honor-body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--color-text-muted);
  max-width: 560px;
}

/* ===== 运营原则 ===== */
.page-about .about-principle-section {
  background: var(--color-primary);
  color: #ffffff;
  padding: var(--about-mobile-pad);
}

.page-about .about-principle-section .eyebrow {
  color: var(--color-accent-light);
}

.page-about .about-principle-section h2 {
  color: #ffffff;
}

.page-about .about-principle-section .section-desc {
  color: rgba(255, 255, 255, 0.66);
}

.page-about .principle-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin-top: 36px;
}

.page-about .principle-card {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.09);
  border-top: 2px solid var(--color-accent);
  padding: 24px;
}

.page-about .principle-card h3 {
  margin: 0 0 10px;
  font-family: var(--font-heading);
  font-size: 20px;
  font-weight: 700;
  color: #ffffff;
}

.page-about .principle-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.75;
  color: rgba(255, 255, 255, 0.72);
}

.page-about .principle-links {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 20px;
  margin-top: 40px;
  padding-top: 24px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.page-about .links-label {
  margin: 0;
  font-size: 13px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--color-accent-light);
}

.page-about .principle-links a {
  color: rgba(255, 255, 255, 0.82);
  text-decoration: none;
  font-size: 15px;
  border-bottom: 1px dashed rgba(255, 255, 255, 0.3);
  padding-bottom: 2px;
  transition: color var(--transition-fast), border-color var(--transition-fast);
}

.page-about .principle-links a:hover {
  color: var(--color-accent-light);
  border-color: var(--color-accent-light);
}

/* ===== 桌面端布局 ===== */
@media (min-width: 900px) {
  .page-about {
    --about-mobile-pad: var(--space-xl) 0;
  }

  .page-about .hero-layout {
    grid-template-columns: 7fr 4fr;
    gap: 72px;
    align-items: start;
    padding-top: var(--space-lg);
  }

  .page-about .hero-fact-card {
    margin-top: 16px;
  }

  .page-about .about-timeline {
    margin-top: 56px;
    padding: 0 40px;
  }

  .page-about .about-timeline::before {
    left: 50%;
    transform: translateX(-50%);
  }

  .page-about .about-timeline .timeline-item {
    width: 50%;
    padding-left: 0;
    padding-right: 48px;
    text-align: right;
    margin-bottom: 40px;
  }

  .page-about .about-timeline .timeline-item:nth-child(even) {
    margin-left: 50%;
    padding-right: 0;
    padding-left: 48px;
    text-align: left;
  }

  .page-about .about-timeline .timeline-dot {
    left: auto;
    right: -9px;
    top: 8px;
  }

  .page-about .about-timeline .timeline-item:nth-child(even) .timeline-dot {
    right: auto;
    left: -9px;
  }

  .page-about .about-timeline details {
    border-bottom: none;
    padding: 0;
  }

  .page-about .about-timeline summary {
    justify-content: flex-end;
    text-align: right;
    font-size: 23px;
  }

  .page-about .about-timeline .timeline-item:nth-child(even) summary {
    justify-content: flex-start;
    text-align: left;
  }

  .page-about .about-timeline summary::before {
    order: 1;
  }

  .page-about .about-timeline .timeline-item:nth-child(even) summary::before {
    order: 0;
  }

  .page-about .about-timeline details p {
    margin: 12px 0 0 auto;
  }

  .page-about .about-timeline .timeline-item:nth-child(even) details p {
    margin: 12px auto 0 0;
  }

  .page-about .data-layout {
    grid-template-columns: 5fr 7fr;
    gap: 64px;
    align-items: start;
  }

  .page-about .data-chart {
    max-width: 100%;
  }

  .page-about .data-grid {
    grid-template-columns: 1fr 1fr;
    gap: 18px;
  }

  .page-about .data-extra {
    max-height: 0;
    opacity: 0;
    overflow: hidden;
  }

  .page-about .data-card:hover .data-extra,
  .page-about .data-card:focus-within .data-extra {
    max-height: 44px;
    opacity: 1;
  }

  .page-about .honor-layout {
    grid-template-columns: 4fr 8fr;
    gap: 64px;
    align-items: start;
  }

  .page-about .honor-badge {
    position: sticky;
    top: 90px;
    max-width: 340px;
  }

  .page-about .honor-card {
    padding: 28px 0;
  }

  .page-about .principle-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
  }

  .page-about .principle-card {
    padding: 28px 24px;
  }

  .page-about .principle-links {
    gap: 14px 24px;
  }
}