.page-about {
  --page-bg: var(--bg-light);
  background: var(--page-bg);
  position: relative;
  overflow-x: hidden;
}

/* 面包屑 – 仅调整间距 */
.page-about .breadcrumb {
  padding-top: 24px;
  padding-bottom: 16px;
}
.page-about .breadcrumb-sep {
  margin: 0 8px;
  color: var(--text-medium);
}

/* ===== 首屏分屏 ===== */
.page-about .hero-split {
  display: flex;
  flex-direction: column;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 20px 48px;
}
@media (min-width: 768px) {
  .page-about .hero-split {
    flex-direction: row;
    align-items: center;
    min-height: 70vh;
  }
}
.page-about .hero-text {
  flex: 1 1 50%;
  padding: 32px 0;
}
.page-about .hero-text h1 {
  font-family: var(--font-headings);
  font-size: 2.8rem;
  line-height: 1.1;
  color: var(--primary);
  margin-bottom: 24px;
  position: relative;
}
.page-about .hero-text h1::after {
  content: '';
  display: block;
  width: 80px;
  height: 4px;
  background: var(--accent);
  margin-top: 12px;
}
.page-about .hero-text p {
  font-family: var(--font-body);
  font-size: 1.05rem;
  color: var(--text-medium);
  line-height: 1.7;
  margin-bottom: 16px;
}
.page-about .hero-visual {
  flex: 1 1 50%;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 24px 0;
}
.page-about .hero-visual img {
  max-width: 100%;
  height: auto;
  border-radius: var(--radius);
  box-shadow: var(--shadow-md);
  object-fit: cover;
}

/* ==== tooltip 关键词 ==== */
.page-about .tooltip-word {
  position: relative;
  color: var(--accent);
  border-bottom: 1px dashed var(--accent);
  cursor: default;
}
.page-about .tooltip-word::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: 120%;
  left: 50%;
  transform: translateX(-50%);
  white-space: nowrap;
  background: var(--primary-dark);
  color: var(--text-on-primary);
  padding: 6px 12px;
  border-radius: var(--radius);
  font-size: 0.85rem;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition);
  z-index: 10;
}
.page-about .tooltip-word:hover::after {
  opacity: 1;
}

/* ===== 主题带 ===== */
.page-about .theme-stripe {
  background: var(--accent);
  padding: 16px 20px;
  margin: 0 auto;
  max-width: var(--container-max);
  border-radius: 0;
  position: relative;
  overflow: hidden;
}
.page-about .theme-stripe span {
  display: block;
  font-family: var(--font-headings);
  font-size: 1.6rem;
  color: var(--text-on-primary);
  text-align: center;
  position: relative;
  z-index: 1;
}
.page-about .theme-stripe::before {
  content: '';
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 100%;
  background: repeating-linear-gradient(45deg, transparent, transparent 20px, rgba(0,0,0,0.1) 20px, rgba(0,0,0,0.1) 21px);
}

/* ===== 核心功能卡片（翻转） ===== */
.page-about .cards-section {
  padding: 48px 20px;
}
.page-about .card-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
  justify-content: center;
  max-width: var(--container-max);
  margin: 0 auto;
}
.page-about .flip-card {
  width: 280px;
  height: 320px;
  perspective: 1000px;
  cursor: default;
}
.page-about .flip-inner {
  position: relative;
  width: 100%;
  height: 100%;
  transition: transform 0.6s ease;
  transform-style: preserve-3d;
}
.page-about .flip-card:hover .flip-inner,
.page-about .flip-card:focus-within .flip-inner {
  transform: rotateY(180deg);
}
.page-about .flip-front,
.page-about .flip-back {
  position: absolute;
  width: 100%;
  height: 100%;
  backface-visibility: hidden;
  border-radius: var(--radius);
  background: var(--bg-white);
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 24px;
  text-align: center;
  border: 1px solid var(--border);
}
.page-about .flip-back {
  transform: rotateY(180deg);
  background: var(--primary);
  color: var(--text-on-primary);
}
.page-about .flip-back p {
  font-family: var(--font-body);
  font-size: 0.95rem;
  line-height: 1.5;
}
.page-about .card-icon {
  font-size: 3rem;
  margin-bottom: 12px;
}
.page-about .flip-front h3 {
  font-family: var(--font-headings);
  font-size: 1.4rem;
  color: var(--primary);
}
@media (min-width: 768px) {
  .page-about .card-grid {
    gap: 32px;
  }
  .page-about .flip-card {
    width: 300px;
    height: 340px;
  }
}

/* ===== 数据精准性 ===== */
.page-about .data-precision {
  padding: 48px 20px;
  background: var(--bg-white);
  border-top: 2px dashed var(--border);
  border-bottom: 2px dashed var(--border);
}
.page-about .precision-content {
  display: flex;
  flex-direction: column;
  gap: 24px;
  max-width: var(--container-max);
  margin: 0 auto;
}
.page-about .precision-text {
  flex: 1;
}
.page-about .precision-text p {
  font-family: var(--font-body);
  color: var(--text-medium);
  line-height: 1.75;
  margin-bottom: 16px;
}
.page-about .precision-text .btn {
  margin-top: 8px;
}
.page-about .precision-image {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
}
.page-about .precision-image img {
  max-width: 100%;
  height: auto;
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  object-fit: cover;
}
@media (min-width: 768px) {
  .page-about .precision-content {
    flex-direction: row;
    align-items: center;
  }
}

/* ===== 持续改进 ===== */
.page-about .continuous-improvement {
  padding: 48px 20px;
}
.page-about .improvement-content {
  display: flex;
  flex-direction: column;
  gap: 24px;
  max-width: var(--container-max);
  margin: 0 auto;
}
.page-about .improvement-image {
  flex: 0 0 auto;
  display: flex;
  justify-content: center;
}
.page-about .improvement-image img {
  max-width: 100%;
  height: auto;
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  object-fit: cover;
}
.page-about .improvement-text {
  flex: 1;
}
.page-about .improvement-text p {
  font-family: var(--font-body);
  color: var(--text-medium);
  line-height: 1.75;
  margin-bottom: 16px;
}
.page-about .improvement-text a {
  color: var(--accent);
  text-decoration: underline;
  font-weight: bold;
}
.page-about .improvement-text .btn {
  margin-top: 8px;
}
@media (min-width: 768px) {
  .page-about .improvement-content {
    flex-direction: row;
    align-items: center;
  }
  .page-about .improvement-image {
    order: 1;
  }
  .page-about .improvement-text {
    order: 0;
  }
}

/* ===== 底部数据流背景 ===== */
.page-about .data-bg {
  height: 120px;
  background: 
    linear-gradient(135deg, var(--primary) 25%, transparent 25%) -50px 0,
    linear-gradient(225deg, var(--primary) 25%, transparent 25%) -50px 0,
    linear-gradient(315deg, var(--primary) 25%, transparent 25%),
    linear-gradient(45deg, var(--primary) 25%, transparent 25%);
  background-size: 40px 40px;
  background-color: var(--bg-light);
  margin-top: -2px;
  opacity: 0.12;
}

/* ===== 响应式微调 ===== */
@media (max-width: 767px) {
  .page-about .hero-text h1 {
    font-size: 2rem;
  }
  .page-about .theme-stripe span {
    font-size: 1.2rem;
  }
  .page-about .flip-card {
    width: 100%;
    max-width: 340px;
    height: 300px;
  }
  .page-about .data-bg {
    height: 80px;
  }
}