* { margin: 0; padding: 0; box-sizing: border-box; }
body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background-color: var(--light);
  color: var(--dark);
  line-height: 1.6;
}
/* 导航与卡片样式 */
.navbar-light .navbar-nav .nav-link {
  color: var(--dark-gray);
  font-weight: 500;
  padding: 0.5rem 1rem;
  transition: 0.2s;
}
.navbar-light .navbar-nav .nav-link:hover {
  color: var(--primary);
}
.btn-primary-custom {
  background-color: var(--primary);
  border: none;
  color: #fff;
  font-weight: 600;
  padding: 10px 28px;
  border-radius: 60px;
  transition: all 0.2s;
  box-shadow: 0 2px 8px rgba(59, 130, 246, 0.25);
}
.btn-primary-custom:hover {
  background-color: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(59, 130, 246, 0.35);
  color: #fff;
}
.btn-outline-custom {
  background: transparent;
  border: 1.5px solid var(--medium-gray);
  color: var(--dark);
  border-radius: 60px;
  padding: 10px 28px;
  font-weight: 500;
  transition: 0.2s;
}
.btn-outline-custom:hover {
  border-color: var(--primary);
  background: var(--primary-light);
  color: var(--primary);
}
.section-title {
  font-weight: 700;
  font-size: 2.5rem;
  letter-spacing: -0.02em;
  color: var(--dark);
}
.section-sub {
  color: var(--dark-gray);
  font-size: 1.15rem;
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
}
.card-glass {
  background: #ffffff;
  border: 1px solid var(--medium-gray);
  border-radius: 24px;
  box-shadow: var(--shadow-light);
  transition: all 0.25s ease;
  height: 100%;
}
.card-glass:hover {
  box-shadow: var(--shadow);
  border-color: var(--primary);
  transform: translateY(-4px);
}
.icon-box-light {
  width: 64px;
  height: 64px;
  border-radius: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--primary-light);
  color: var(--primary);
  font-size: 2rem;
  transition: 0.3s;
}
.badge-soft-blue {
  background: var(--primary-light);
  color: var(--primary);
  padding: 6px 16px;
  border-radius: 40px;
  font-weight: 500;
  font-size: 0.85rem;
}
.case-stat {
  font-size: 2.4rem;
  font-weight: 700;
  color: var(--dark);
  letter-spacing: -0.02em;
}
.case-stat-label {
  color: var(--dark-gray);
  font-size: 0.95rem;
}
.footer-link {
  color: var(--dark-gray);
  text-decoration: none;
  transition: 0.2s;
}
.footer-link:hover {
  color: var(--primary);
}
.border-bottom-light {
  border-bottom: 1px solid var(--medium-gray);
}
/* 亮色背景区块 */
.bg-white-section {
  background: #ffffff;
}
.bg-light-section {
  background: var(--light);
}
@media (max-width: 768px) {
  .section-title { font-size: 2rem; }
  .hero-title { font-size: 2.2rem !important; }
}

@keyframes pulseGlow {
  0% { transform: scale(1); opacity: 0.2; }
  50% { transform: scale(1.2); opacity: 0.6; }
  100% { transform: scale(1); opacity: 0.2; }
}
html { scroll-behavior: smooth; }

/* AIoT Hero Section */
.hero-aiot {
  background-image: url('../images/4.png');
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  padding: 160px 0 60px; /* Account for fixed navbar */
  min-height: 700px;
  position: relative;
  background-color: #f8faff; /* fallback */
  overflow: hidden;
}

.hero-aiot .tag-blue {
  background-color: #e6f0ff;
  color: #0d6efd;
  font-weight: 500;
  padding: 8px 16px;
  font-size: 0.9rem;
}

.hero-aiot .tag-purple {
  background-color: #f3e8ff;
  color: #7c3aed;
  font-weight: 500;
  padding: 8px 16px;
  font-size: 0.9rem;
}

.hero-aiot .tag-green {
  background-color: #d1fae5;
  color: #059669;
  font-weight: 500;
  padding: 8px 16px;
  font-size: 0.9rem;
}

.hero-aiot .hero-title {
  font-size: 2.8rem;
  line-height: 1.4;
  color: #1a1a1a;
  letter-spacing: -0.02em;
}

.hero-aiot .text-primary-gradient {
  color: #0d6efd;
}

.hero-aiot .hero-subtitle {
  font-size: 1.15rem;
  color: #4b5563;
}

.hero-aiot .features-grid {
  display: flex;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.hero-aiot .feature-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  font-size: 0.9rem;
  color: #4b5563;
  font-weight: 600;
  background: transparent;
  padding: 12px 16px;
  border-radius: 16px;
  box-shadow: none;
  backdrop-filter: none;
  background-color: white;
}

.hero-aiot .feature-icon-wrapper {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
  background: transparent;
  box-shadow: none;
  color: var(--primary);
}

.hero-aiot .right-graphic {
  max-width: 110%;
  margin-left: -5%;
  animation: float 6s ease-in-out infinite;
}

@keyframes float {
  0% { transform: translateY(-15px); }
  50% { transform: translateY(5px); }
  100% { transform: translateY(-15px); }
}

.hero-aiot .stats-card {
  background: #ffffff;
  border-radius: 24px;
  padding: 30px 40px;
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.06);
  position: relative;
  z-index: 10;
}

.hero-aiot .stat-icon {
  font-size: 1.8rem;
  width: 48px;
  height: 48px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-aiot .solution-badge-green {
  background-color: #d1fae5;
  color: #059669;
  padding: 8px 16px;
  font-weight: 500;
  border-radius: 8px;
}

.hero-aiot .solution-badge-blue {
  background-color: #e0f2fe;
  color: #0284c7;
  padding: 8px 16px;
  font-weight: 500;
  border-radius: 8px;
}

.hero-aiot .solution-badge-orange {
  background-color: #ffedd5;
  color: #ea580c;
  padding: 8px 16px;
  font-weight: 500;
  border-radius: 8px;
}

@media (max-width: 991px) {
  .hero-aiot {
    padding-top: 160px;
  }
  .hero-aiot .right-graphic {
    max-width: 100%;
    margin-left: 0;
    margin-top: 40px;
  }
  .hero-aiot .hero-title {
    font-size: 2.2rem;
  }
  .hero-aiot .stats-card {
    padding: 20px;
  }
  .hero-aiot .stats-card .border-start {
    border-left: none !important;
    padding-top: 20px;
    border-top: 1px solid #dee2e6;
  }
}