.page-about {
  --panel-width: 280px;
  --deco-size: 80px;
  --timeline-dot-size: 16px;
  position: relative;
  background-color: var(--clr-bg, #F5F5F0);
  min-height: 100vh;
  padding: var(--space-lg, 2rem) var(--space-md, 1rem) var(--space-2xl, 5rem);
}

/* 面包屑 */
.page-about .breadcrumb {
  display: flex;
  align-items: center;
  gap: var(--space-sm, 0.5rem);
  font-family: var(--font-body, system-ui, -apple-system, 'Segoe UI', sans-serif);
  font-size: var(--body-size, 1rem);
  color: var(--clr-text-secondary, #4A4A4A);
  margin-bottom: var(--space-xl, 3rem);
  max-width: var(--max-width, 1200px);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-md, 1rem);
}

.page-about .breadcrumb__link {
  color: var(--clr-primary, #0A562B);
  text-decoration: none;
  font-weight: 500;
  transition: color var(--transition, 0.25s ease);
}

.page-about .breadcrumb__link:hover,
.page-about .breadcrumb__link:focus-visible {
  color: var(--clr-gold, #D4AF37);
  outline: 2px solid var(--clr-focus, #D4AF37);
  outline-offset: 2px;
}

.page-about .breadcrumb__sep {
  color: var(--clr-gold, #D4AF37);
  font-weight: 700;
  margin: 0 var(--space-xs, 0.25rem);
}

/* 主布局 */
.page-about .about-layout {
  max-width: var(--max-width, 1200px);
  margin-left: auto;
  margin-right: auto;
  display: flex;
  flex-direction: column;
  gap: var(--space-xl, 3rem);
}

/* 左侧展板 */
.page-about .about-panel {
  background-color: var(--clr-primary, #0A562B);
  padding: var(--space-xl, 3rem) var(--space-lg, 2rem);
  position: relative;
  overflow: hidden;
  border: var(--border-thick, 4px) solid var(--clr-primary-dark, #063A1D);
  box-shadow: var(--shadow-strong, 8px 8px 0 rgba(10, 86, 43, 0.25));
}

.page-about .about-panel__title {
  font-family: var(--font-heading, system-ui, -apple-system, 'Helvetica Neue', sans-serif);
  font-size: 2.5rem;
  font-weight: var(--heading-weight, 900);
  letter-spacing: var(--heading-tracking, -0.02em);
  color: #fff;
  margin: 0;
  line-height: 1.1;
  text-transform: uppercase;
}

.page-about .about-panel__divider {
  width: 80px;
  height: var(--border-thick, 4px);
  background-color: var(--clr-gold, #D4AF37);
  margin: var(--space-lg, 2rem) 0 var(--space-md, 1rem);
}

.page-about .about-panel__sub {
  font-family: var(--font-body, system-ui, -apple-system, 'Segoe UI', sans-serif);
  font-size: 1rem;
  color: var(--clr-gold-light, #E8D488);
  margin: 0;
  font-weight: 500;
  letter-spacing: 0.04em;
}

.page-about .about-panel__deco {
  position: absolute;
  bottom: -20px;
  right: -20px;
  width: var(--deco-size, 80px);
  height: var(--deco-size, 80px);
  border: 4px solid var(--clr-gold, #D4AF37);
  opacity: 0.25;
  transform: rotate(45deg);
  pointer-events: none;
}

/* 右侧内容区 */
.page-about .about-content {
  display: flex;
  flex-direction: column;
  gap: var(--space-2xl, 5rem);
}

/* 通用section */
.page-about .about-section {
  position: relative;
}

.page-about .about-section__title {
  font-family: var(--font-heading, system-ui, -apple-system, 'Helvetica Neue', sans-serif);
  font-size: 1.75rem;
  font-weight: var(--heading-weight, 900);
  letter-spacing: var(--heading-tracking, -0.02em);
  color: var(--clr-primary, #0A562B);
  margin: 0 0 var(--space-lg, 2rem);
  padding-bottom: var(--space-sm, 0.5rem);
  border-bottom: 3px solid var(--clr-gold, #D4AF37);
  display: inline-block;
}

.page-about .about-section__text {
  font-family: var(--font-body, system-ui, -apple-system, 'Segoe UI', sans-serif);
  font-size: 1.05rem;
  color: var(--clr-text, #1A1A1A);
  line-height: 1.7;
  margin: 0 0 var(--space-md, 1rem);
  max-width: 72ch;
}

.page-about .about-section__text strong {
  color: var(--clr-primary, #0A562B);
  font-weight: 700;
}

/* 核心能力 — 时间轴 */
.page-about .capabilities-wrap {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg, 2rem);
}

.page-about .timeline {
  position: relative;
  padding-left: calc(var(--timeline-dot-size, 16px) + var(--space-lg, 2rem));
  flex: 1;
}

.page-about .timeline::before {
  content: '';
  position: absolute;
  left: calc(var(--timeline-dot-size, 16px) / 2);
  top: 0;
  bottom: 0;
  width: 3px;
  background-color: var(--clr-gold, #D4AF37);
  opacity: 0.5;
}

.page-about .timeline__item {
  position: relative;
  margin-bottom: var(--space-lg, 2rem);
  background-color: #fff;
  border: var(--border-thick, 4px) solid var(--clr-border, #D4AF37);
  box-shadow: var(--shadow-strong, 8px 8px 0 rgba(10, 86, 43, 0.25));
  transition: box-shadow var(--transition, 0.25s ease), transform var(--transition, 0.25s ease);
  list-style: none;
}

.page-about .timeline__item:hover {
  box-shadow: var(--shadow-hover, 12px 12px 0 rgba(10, 86, 43, 0.3));
  transform: translate(-2px, -2px);
}

.page-about .timeline__item[open] .timeline__expand {
  transform: rotate(45deg);
}

.page-about .timeline__header {
  display: flex;
  align-items: center;
  gap: var(--space-sm, 0.5rem);
  padding: var(--space-md, 1rem) var(--space-lg, 2rem);
  cursor: pointer;
  user-select: none;
  font-family: var(--font-heading, system-ui, -apple-system, 'Helvetica Neue', sans-serif);
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--clr-primary, #0A562B);
  letter-spacing: -0.01em;
  position: relative;
}

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

.page-about .timeline__header::marker {
  display: none;
  content: '';
}

.page-about .timeline__dot {
  position: absolute;
  left: calc(-1 * (var(--timeline-dot-size, 16px) + var(--space-lg, 2rem) + var(--timeline-dot-size, 16px) / 2));
  top: 1.2rem;
  width: var(--timeline-dot-size, 16px);
  height: var(--timeline-dot-size, 16px);
  border-radius: 50%;
  background-color: var(--clr-gold, #D4AF37);
  border: 3px solid var(--clr-primary-dark, #063A1D);
  flex-shrink: 0;
  z-index: 1;
}

.page-about .timeline__label {
  flex: 1;
}

.page-about .timeline__expand {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  font-size: 1.5rem;
  font-weight: 300;
  color: var(--clr-gold, #D4AF37);
  transition: transform var(--transition, 0.25s ease);
  line-height: 1;
}

.page-about .timeline__body {
  padding: 0 var(--space-lg, 2rem) var(--space-md, 1rem);
  border-top: 1px solid var(--clr-bg-dark, #E0E0D8);
  padding-top: var(--space-md, 1rem);
}

.page-about .timeline__desc {
  font-family: var(--font-body, system-ui, -apple-system, 'Segoe UI', sans-serif);
  font-size: 0.95rem;
  color: var(--clr-text-secondary, #4A4A4A);
  line-height: 1.6;
  margin: 0 0 var(--space-md, 1rem);
}

.page-about .timeline__link {
  display: inline-block;
}

/* 时间轴按钮 */
.page-about .btn--outline {
  display: inline-flex;
  align-items: center;
  padding: var(--space-sm, 0.5rem) var(--space-md, 1rem);
  font-family: var(--font-body, system-ui, -apple-system, 'Segoe UI', sans-serif);
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--clr-primary, #0A562B);
  background-color: transparent;
  border: 3px solid var(--clr-primary, #0A562B);
  text-decoration: none;
  letter-spacing: 0.02em;
  transition: background-color var(--transition, 0.25s ease), color var(--transition, 0.25s ease), border-color var(--transition, 0.25s ease);
  cursor: pointer;
}

.page-about .btn--outline:hover,
.page-about .btn--outline:focus-visible {
  background-color: var(--clr-primary, #0A562B);
  color: #fff;
  border-color: var(--clr-gold, #D4AF37);
  outline: 2px solid var(--clr-focus, #D4AF37);
  outline-offset: 2px;
}

/* 核心能力配图 */
.page-about .capabilities-visual {
  flex-shrink: 0;
  width: 100%;
  max-width: 800px;
  margin: 0 auto;
}

.page-about .capabilities-img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border: var(--border-thick, 4px) solid var(--clr-border, #D4AF37);
  box-shadow: var(--shadow-strong, 8px 8px 0 rgba(10, 86, 43, 0.25));
}

/* 为什么选择我们 — 卡片网格 */
.page-about .benefits-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-lg, 2rem);
}

.page-about .benefit-card {
  background-color: #fff;
  border: var(--border-thick, 4px) solid var(--clr-border, #D4AF37);
  box-shadow: var(--shadow-strong, 8px 8px 0 rgba(10, 86, 43, 0.25));
  padding: var(--space-lg, 2rem);
  transition: box-shadow var(--transition, 0.25s ease), transform var(--transition, 0.25s ease);
  display: flex;
  flex-direction: column;
  gap: var(--space-sm, 0.5rem);
}

.page-about .benefit-card:hover {
  box-shadow: var(--shadow-hover, 12px 12px 0 rgba(10, 86, 43, 0.3));
  transform: translate(-2px, -2px);
}

.page-about .benefit-card__icon {
  width: 60px;
  height: 60px;
  margin-bottom: var(--space-sm, 0.5rem);
  flex-shrink: 0;
}

.page-about .benefit-card__icon img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.page-about .benefit-card__icon--alt svg {
  display: block;
  width: 100%;
  height: 100%;
}

.page-about .benefit-card__title {
  font-family: var(--font-heading, system-ui, -apple-system, 'Helvetica Neue', sans-serif);
  font-size: 1.2rem;
  font-weight: var(--heading-weight, 900);
  letter-spacing: var(--heading-tracking, -0.02em);
  color: var(--clr-primary, #0A562B);
  margin: 0;
}

.page-about .benefit-card__text {
  font-family: var(--font-body, system-ui, -apple-system, 'Segoe UI', sans-serif);
  font-size: 0.95rem;
  color: var(--clr-text-secondary, #4A4A4A);
  line-height: 1.6;
  margin: 0;
}

/* 服务承诺 */
.page-about .commitment-content {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg, 2rem);
  background-color: #fff;
  border: var(--border-thick, 4px) solid var(--clr-border, #D4AF37);
  box-shadow: var(--shadow-strong, 8px 8px 0 rgba(10, 86, 43, 0.25));
  padding: var(--space-lg, 2rem);
}

.page-about .commitment__text {
  flex: 1;
}

.page-about .commitment__text p {
  font-family: var(--font-body, system-ui, -apple-system, 'Segoe UI', sans-serif);
  font-size: 1rem;
  color: var(--clr-text, #1A1A1A);
  line-height: 1.7;
  margin: 0 0 var(--space-md, 1rem);
  max-width: 72ch;
}

.page-about .commitment__text p strong {
  color: var(--clr-primary, #0A562B);
}

.page-about .commitment__contact {
  list-style: none;
  padding: 0;
  margin: 0 0 var(--space-lg, 2rem);
  display: flex;
  flex-direction: column;
  gap: var(--space-sm, 0.5rem);
}

.page-about .commitment__contact li {
  font-family: var(--font-body, system-ui, -apple-system, 'Segoe UI', sans-serif);
  font-size: 0.95rem;
  color: var(--clr-text-secondary, #4A4A4A);
  line-height: 1.5;
}

.page-about .commitment__contact li strong {
  color: var(--clr-primary, #0A562B);
  font-weight: 600;
  display: inline-block;
  min-width: 4em;
}

.page-about .commitment__visual {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-md, 1rem);
}

.page-about .commitment__visual svg {
  display: block;
  max-width: 120px;
  height: auto;
}

/* 滚动显现 */
.page-about [data-reveal] {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.page-about [data-reveal].revealed {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  .page-about [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }
  .page-about .benefit-card,
  .page-about .timeline__item,
  .page-about .btn--outline {
    transition: none;
  }
  .page-about .timeline__item:hover,
  .page-about .benefit-card:hover {
    transform: none;
    box-shadow: var(--shadow-strong, 8px 8px 0 rgba(10, 86, 43, 0.25));
  }
}

/* 桌面端布局 ≥768px */
@media (min-width: 768px) {
  .page-about {
    padding: var(--space-xl, 3rem) var(--space-lg, 2rem) var(--space-2xl, 5rem);
  }

  .page-about .about-layout {
    flex-direction: row;
    align-items: flex-start;
    gap: var(--space-xl, 3rem);
  }

  .page-about .about-panel {
    width: var(--panel-width, 280px);
    flex-shrink: 0;
    position: sticky;
    top: var(--space-lg, 2rem);
    padding: var(--space-xl, 3rem) var(--space-lg, 2rem);
    min-height: 360px;
    display: flex;
    flex-direction: column;
    justify-content: center;
  }

  .page-about .about-panel__title {
    font-size: 3.2rem;
  }

  .page-about .about-panel__sub {
    font-size: 1.1rem;
  }

  .page-about .about-content {
    flex: 1;
    min-width: 0;
  }

  .page-about .about-section__title {
    font-size: 2rem;
  }

  .page-about .capabilities-wrap {
    flex-direction: row;
    align-items: flex-start;
    gap: var(--space-xl, 3rem);
  }

  .page-about .timeline {
    flex: 1;
  }

  .page-about .capabilities-visual {
    width: 380px;
    flex-shrink: 0;
    margin-top: var(--space-sm, 0.5rem);
  }

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

  .page-about .commitment-content {
    flex-direction: row;
    align-items: flex-start;
    gap: var(--space-xl, 3rem);
  }

  .page-about .commitment__visual {
    width: 160px;
    justify-content: flex-end;
  }
}

/* 大桌面端 ≥1024px */
@media (min-width: 1024px) {
  .page-about .about-panel__title {
    font-size: 3.8rem;
  }

  .page-about .about-section__title {
    font-size: 2.25rem;
  }

  .page-about .capabilities-visual {
    width: 480px;
  }

  .page-about .benefits-grid {
    gap: var(--space-xl, 3rem);
  }
}

.page-about {
  --heading-tracking: normal;
  --heading-weight: 600;
}