.page-about {
  --hero-grid-gap: 64px;
  --timeline-dot-size: 16px;
  --service-card-minh: 280px;
  --why-index-size: 40px;
  display: block;
  padding-top: 72px;
}

/* 面包屑 */
.page-about__breadcrumb {
  padding: var(--sp-md) 0 0;
}
.page-about__breadcrumb .breadcrumb {
  display: flex;
  gap: var(--sp-sm);
  list-style: none;
  font-family: var(--font-ui);
  font-size: var(--size-small);
  color: var(--color-neutral-3);
}
.page-about__breadcrumb .breadcrumb__item:not(:last-child)::after {
  content: "/";
  margin-left: var(--sp-sm);
  color: var(--color-border);
}
.page-about__breadcrumb .breadcrumb__link {
  color: var(--color-secondary-2);
  text-decoration: none;
}
.page-about__breadcrumb .breadcrumb__link:hover {
  color: var(--color-accent);
}

/* 首屏 */
.page-about__hero {
  padding: var(--sp-xl) 0 var(--sp-lg);
}
.page-about__hero-inner {
  display: flex;
  flex-direction: column;
  gap: var(--hero-grid-gap);
  align-items: stretch;
}
.page-about__hero-left {
  position: relative;
  order: 2;
}
.page-about__hero-coord {
  position: absolute;
  top: -8px;
  left: 0;
}
.page-about__hero-title {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--size-h1);
  color: var(--color-primary);
  margin: 0 0 var(--sp-xs);
  line-height: 1.1;
}
.page-about__hero-tagline {
  font-family: var(--font-heading);
  font-weight: var(--weight-bold);
  font-size: var(--size-h3);
  color: var(--color-secondary-2);
  margin: 0 0 var(--sp-md);
}
.page-about__hero-desc {
  font-family: var(--font-body);
  font-size: var(--size-body);
  color: var(--color-neutral-3);
  line-height: var(--line-body);
  max-width: 480px;
}
.page-about__hero-right {
  order: 1;
}
.page-about__hero-img {
  width: 100%;
  max-width: 600px;
  height: auto;
  object-fit: cover;
  display: block;
  border-radius: var(--radius);
  box-shadow: 0 2px 8px var(--color-shadow);
}

/* 时间轴 */
.page-about__timeline {
  padding: var(--sp-lg) 0;
  position: relative;
}
.page-about__timeline-coord {
  position: absolute;
  top: var(--sp-lg);
  left: calc((100% - 1200px) / 2 + 16px);
  z-index: 1;
}
.page-about__timeline-intro {
  font-family: var(--font-body);
  font-size: var(--size-body);
  color: var(--color-neutral-3);
  margin-bottom: var(--sp-lg);
  max-width: 600px;
}
.page-about__timeline-list {
  display: flex;
  flex-direction: column;
  gap: var(--sp-lg);
  list-style: none;
  padding: 0;
  margin: 0;
  position: relative;
}
.page-about__timeline-list::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: linear-gradient(to bottom, var(--color-secondary-1), var(--color-primary), var(--color-accent));
}
.page-about__timeline-node {
  display: flex;
  gap: var(--sp-md);
  align-items: flex-start;
  position: relative;
}
.page-about__timeline-dot {
  width: var(--timeline-dot-size);
  height: var(--timeline-dot-size);
  border-radius: 50%;
  background: radial-gradient(circle, var(--color-secondary-1), var(--color-primary));
  flex-shrink: 0;
  margin-top: 4px;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  box-shadow: 0 0 0 2px var(--color-neutral-1);
}
.page-about__timeline-node[data-timeline]:hover .page-about__timeline-dot {
  transform: scale(1.3);
  box-shadow: 0 0 12px var(--color-secondary-1);
}
.page-about__timeline-content {
  font-family: var(--font-body);
}
.page-about__timeline-label {
  font-family: var(--font-heading);
  font-weight: var(--weight-bold);
  font-size: var(--size-h4);
  color: var(--color-secondary-2);
  margin: 0 0 var(--sp-xs);
}
.page-about__timeline-text {
  font-size: var(--size-body);
  color: var(--color-neutral-3);
  line-height: var(--line-body);
  margin: 0;
}

/* 服务卡片 */
.page-about__services {
  padding: var(--sp-lg) 0;
  position: relative;
}
.page-about__services-coord {
  position: absolute;
  top: var(--sp-lg);
  left: calc((100% - 1200px) / 2 + 16px);
  z-index: 1;
}
.page-about__services-grid {
  margin-top: var(--sp-md);
  display: grid;
  gap: var(--sp-lg);
  grid-template-columns: 1fr;
}
.page-about__service-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  text-decoration: none;
  color: inherit;
  min-height: var(--service-card-minh);
  padding: var(--sp-lg) var(--sp-md);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-neutral-1);
  box-shadow: 0 1px 4px var(--color-shadow);
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}
.page-about__service-card:hover {
  border-color: var(--color-primary);
  box-shadow: 0 4px 16px var(--color-shadow);
}
.page-about__service-icon {
  width: 120px;
  height: 120px;
  object-fit: contain;
  display: block;
  margin-bottom: var(--sp-md);
}
.page-about__service-title {
  font-family: var(--font-heading);
  font-weight: var(--weight-bold);
  font-size: var(--size-h4);
  color: var(--color-secondary-2);
  margin: 0 0 var(--sp-sm);
}
.page-about__service-body {
  font-family: var(--font-body);
  font-size: var(--size-body);
  color: var(--color-neutral-3);
  line-height: var(--line-body);
  max-width: 280px;
  margin: 0;
}

/* 为什么选择我们 */
.page-about__why {
  padding: var(--sp-lg) 0;
  position: relative;
}
.page-about__why-coord {
  position: absolute;
  top: var(--sp-lg);
  left: calc((100% - 1200px) / 2 + 16px);
  z-index: 1;
}
.page-about__why-list {
  display: flex;
  flex-direction: column;
  gap: var(--sp-lg);
  margin-top: var(--sp-md);
}
.page-about__why-item {
  display: flex;
  flex-direction: column;
  gap: var(--sp-sm);
  padding: var(--sp-md);
  border-left: 4px solid var(--color-secondary-1);
  background: var(--color-neutral-2);
  border-radius: var(--radius);
}
.page-about__why-index {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--why-index-size);
  color: var(--color-primary);
  line-height: 1;
}
.page-about__why-heading {
  font-family: var(--font-heading);
  font-weight: var(--weight-bold);
  font-size: var(--size-h4);
  color: var(--color-secondary-2);
  margin: 0;
}
.page-about__why-text {
  font-family: var(--font-body);
  font-size: var(--size-body);
  color: var(--color-neutral-3);
  line-height: var(--line-body);
  margin: 0;
}

/* CTA 区域 */
.page-about__cta {
  padding: var(--sp-lg) 0 var(--sp-xl);
  background: var(--color-neutral-2);
  border-top: 1px solid var(--color-border);
}
.page-about__cta-text {
  font-family: var(--font-body);
  font-size: var(--size-body);
  color: var(--color-neutral-3);
  text-align: center;
  margin: 0 0 var(--sp-sm);
}
.page-about__cta-info {
  font-family: var(--font-ui);
  font-size: var(--size-ui);
  color: var(--color-secondary-2);
  text-align: center;
  margin: 0;
}

/* 通用标题 */
.page-about__section-title {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--size-h2);
  color: var(--color-secondary-2);
  margin: 0 0 var(--sp-md);
  position: relative;
  display: inline-block;
}
.page-about__section-title::after {
  content: "";
  display: block;
  width: 60px;
  height: 3px;
  background: var(--color-primary);
  margin-top: var(--sp-sm);
}

/* 桌面布局 */
@media (min-width: 768px) {
  .page-about__hero-inner {
    flex-direction: row;
    align-items: center;
  }
  .page-about__hero-left {
    flex: 1;
    order: 1;
  }
  .page-about__hero-right {
    flex: 1;
    order: 2;
  }
  .page-about__hero-img {
    max-width: 100%;
  }
  .page-about__timeline-list {
    flex-direction: row;
    gap: var(--sp-xl);
    justify-content: space-between;
  }
  .page-about__timeline-list::before {
    left: 0;
    right: 0;
    top: 7px;
    bottom: auto;
    width: auto;
    height: 2px;
  }
  .page-about__timeline-node {
    flex-direction: column;
    align-items: center;
    text-align: center;
    flex: 1;
  }
  .page-about__timeline-dot {
    margin-top: 0;
  }
  .page-about__services-grid {
    grid-template-columns: 1fr 1fr 1fr;
  }
  .page-about__why-list {
    flex-direction: row;
    gap: var(--sp-xl);
  }
  .page-about__why-item {
    flex: 1;
  }
}
@media (min-width: 1200px) {
  .page-about__hero-title {
    font-size: 56px;
  }
}
@media (max-width: 767px) {
  .page-about__timeline-coord,
  .page-about__services-coord,
  .page-about__why-coord {
    position: static;
    display: block;
    margin-bottom: var(--sp-sm);
  }
}