/* ==================== 基础样式 ==================== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --primary-color: #3b82f6;
  --primary-dark: #2563eb;
  --primary-light: #60a5fa;
  --secondary-color: #06b6d4;
  --accent-color: #8b5cf6;
  --text-primary: #1e293b;
  --text-secondary: #64748b;
  --text-light: #94a3b8;
  --bg-primary: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 50%, #f0f9ff 100%);
  --bg-secondary: linear-gradient(135deg, #fefce8 0%, #fef3c7 50%, #fefce8 100%);
  --bg-glass: rgba(255, 255, 255, 0.7);
  --bg-glass-hover: rgba(255, 255, 255, 0.9);
  --border-color: rgba(148, 163, 184, 0.2);
  --border-glass: rgba(255, 255, 255, 0.5);
  --shadow-sm: 0 2px 8px rgba(59, 130, 246, 0.08);
  --shadow-md: 0 8px 24px rgba(59, 130, 246, 0.12);
  --shadow-lg: 0 16px 40px rgba(59, 130, 246, 0.15);
  --shadow-xl: 0 24px 60px rgba(59, 130, 246, 0.2);
  --shadow-glass: 0 8px 32px rgba(31, 38, 135, 0.15);
  --radius-sm: 12px;
  --radius-md: 16px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  color: var(--text-primary);
  line-height: 1.7;
  background: linear-gradient(135deg, #e0f2fe 0%, #dbeafe 25%, #e0e7ff 50%, #ddd6fe 75%, #fae8ff 100%);
  background-size: 400% 400%;
  animation: gradientShift 15s ease infinite;
  overflow-x: hidden;
  position: relative;
}

body.is-scrolling,
body.is-scrolling * {
  animation-play-state: paused;
}

@keyframes gradientShift {
  0%, 100% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
}

/* ==================== 背景装饰 ==================== */
.bg-grid {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image: 
    linear-gradient(rgba(37, 99, 235, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(37, 99, 235, 0.03) 1px, transparent 1px);
  background-size: 50px 50px;
  z-index: -1;
  pointer-events: none;
}

.bg-glow {
  position: fixed;
  border-radius: 50%;
  filter: blur(120px);
  opacity: 0.3;
  z-index: -1;
  pointer-events: none;
  animation: float 20s ease-in-out infinite;
}

.bg-glow-1 {
  width: 700px;
  height: 700px;
  background: radial-gradient(circle, rgba(59, 130, 246, 0.4) 0%, rgba(147, 197, 253, 0.2) 50%, transparent 100%);
  top: -250px;
  right: -250px;
}

.bg-glow-2 {
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(139, 92, 246, 0.4) 0%, rgba(196, 181, 253, 0.2) 50%, transparent 100%);
  bottom: -200px;
  left: -200px;
  animation-delay: -10s;
}

@keyframes float {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(30px, -30px) scale(1.1); }
  66% { transform: translate(-20px, 20px) scale(0.9); }
}

/* ==================== 容器 ==================== */
.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 40px;
}

/* ==================== 导航栏 ==================== */
#header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.6);
  backdrop-filter: blur(30px) saturate(180%);
  -webkit-backdrop-filter: blur(30px) saturate(180%);
  border-bottom: 1px solid rgba(255, 255, 255, 0.3);
  transition: var(--transition);
  box-shadow: 0 4px 24px rgba(59, 130, 246, 0.08);
}

#header.scrolled {
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(40px) saturate(200%);
  -webkit-backdrop-filter: blur(40px) saturate(200%);
  border-bottom-color: rgba(148, 163, 184, 0.2);
  box-shadow: 0 8px 32px rgba(59, 130, 246, 0.12);
}

#header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 80px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  transition: var(--transition);
}

.logo:hover {
  transform: translateY(-2px);
}

.logo-icon {
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, #3b82f6 0%, #06b6d4 50%, #8b5cf6 100%);
  background-size: 200% 200%;
  animation: gradientFlow 3s ease infinite;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 20px;
  font-weight: 700;
  box-shadow: 0 8px 24px rgba(59, 130, 246, 0.4), inset 0 1px 0 rgba(255, 255, 255, 0.3);
  position: relative;
  overflow: hidden;
}

.logo-icon::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: linear-gradient(45deg, transparent, rgba(255, 255, 255, 0.3), transparent);
  transform: rotate(45deg);
  animation: shine 3s infinite;
}

@keyframes gradientFlow {
  0%, 100% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
}

@keyframes shine {
  0% { transform: translateX(-100%) translateY(-100%) rotate(45deg); }
  100% { transform: translateX(100%) translateY(100%) rotate(45deg); }
}

.logo-text {
  font-size: 22px;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.5px;
}

.nav-links {
  display: flex;
  gap: 40px;
  list-style: none;
  align-items: center;
}

.nav-links a {
  text-decoration: none;
  color: var(--text-secondary);
  font-size: 15px;
  font-weight: 500;
  position: relative;
  transition: var(--transition);
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 0;
  width: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
  border-radius: 2px;
  transition: var(--transition);
}

.nav-links a:hover {
  color: var(--primary-color);
}

.nav-links a:hover::after {
  width: 100%;
}

.nav-cta {
  padding: 12px 28px;
  background: linear-gradient(135deg, #3b82f6 0%, #06b6d4 50%, #8b5cf6 100%);
  background-size: 200% 200%;
  animation: gradientFlow 3s ease infinite;
  color: white;
  text-decoration: none;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 600;
  transition: var(--transition);
  box-shadow: 0 8px 24px rgba(59, 130, 246, 0.3), inset 0 1px 0 rgba(255, 255, 255, 0.2);
  position: relative;
  overflow: hidden;
}

.nav-cta::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
  transition: left 0.5s;
}

.nav-cta:hover::before {
  left: 100%;
}

.nav-cta:hover {
  transform: translateY(-3px);
  box-shadow: 0 12px 32px rgba(59, 130, 246, 0.4), inset 0 1px 0 rgba(255, 255, 255, 0.3);
}

.mobile-menu-btn {
  display: none;
  flex-direction: column;
  gap: 6px;
  cursor: pointer;
}

.mobile-menu-btn span {
  width: 28px;
  height: 3px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: var(--transition);
}

/* ==================== 按钮样式 ==================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 16px 32px;
  border-radius: var(--radius-md);
  font-size: 16px;
  font-weight: 600;
  text-decoration: none;
  transition: var(--transition);
  cursor: pointer;
  border: none;
  outline: none;
}

.btn-primary {
  background: linear-gradient(135deg, #3b82f6 0%, #06b6d4 50%, #8b5cf6 100%);
  background-size: 200% 200%;
  animation: gradientFlow 3s ease infinite;
  color: white;
  box-shadow: 0 8px 24px rgba(59, 130, 246, 0.3), inset 0 1px 0 rgba(255, 255, 255, 0.2);
  position: relative;
  overflow: hidden;
}

.btn-primary::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
  transition: left 0.5s;
}

.btn-primary:hover::before {
  left: 100%;
}

.btn-primary:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px rgba(59, 130, 246, 0.4), inset 0 1px 0 rgba(255, 255, 255, 0.3);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  color: var(--primary-color);
  border: 2px solid rgba(59, 130, 246, 0.3);
  box-shadow: 0 4px 16px rgba(59, 130, 246, 0.1), inset 0 1px 0 rgba(255, 255, 255, 0.5);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.95);
  border-color: var(--primary-color);
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(59, 130, 246, 0.2), inset 0 1px 0 rgba(255, 255, 255, 0.7);
}

/* ==================== 区块标题 ==================== */
.section-header {
  text-align: center;
  max-width: 800px;
  margin: 0 auto 80px;
}

.section-tag {
  display: inline-block;
  padding: 10px 24px;
  background: rgba(255, 255, 255, 0.7);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid rgba(59, 130, 246, 0.3);
  color: var(--primary-color);
  border-radius: 24px;
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 20px;
  letter-spacing: 0.5px;
  box-shadow: 0 4px 16px rgba(59, 130, 246, 0.15), inset 0 1px 0 rgba(255, 255, 255, 0.5);
  position: relative;
  overflow: hidden;
}

.section-tag::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, rgba(59, 130, 246, 0.1), rgba(139, 92, 246, 0.1));
  opacity: 0;
  transition: opacity 0.3s;
}

.section-tag:hover::before {
  opacity: 1;
}

.section-header h2 {
  font-size: 42px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 20px;
  line-height: 1.2;
  letter-spacing: -1px;
}

.section-header p {
  font-size: 18px;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* ==================== 卡片样式 ==================== */
.card {
  background: rgba(255, 255, 255, 0.7);
  backdrop-filter: blur(30px) saturate(180%);
  -webkit-backdrop-filter: blur(30px) saturate(180%);
  border-radius: var(--radius-lg);
  padding: 40px;
  border: 1px solid rgba(255, 255, 255, 0.5);
  box-shadow: 0 8px 32px rgba(59, 130, 246, 0.1), inset 0 1px 0 rgba(255, 255, 255, 0.6);
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, rgba(59, 130, 246, 0.05), rgba(139, 92, 246, 0.05));
  opacity: 0;
  transition: opacity 0.3s;
}

.card:hover::before {
  opacity: 1;
}

.card:hover {
  transform: translateY(-12px);
  background: rgba(255, 255, 255, 0.85);
  box-shadow: 0 16px 48px rgba(59, 130, 246, 0.2), inset 0 1px 0 rgba(255, 255, 255, 0.8);
  border-color: rgba(59, 130, 246, 0.3);
}

/* ==================== 响应式 ==================== */
@media (max-width: 1024px) {
  .container {
    padding: 0 30px;
  }
  
  .section-header h2 {
    font-size: 36px;
  }
}

@media (max-width: 768px) {
  .container {
    padding: 0 20px;
  }
  
  #header .container {
    height: 70px;
  }
  
  .nav-links {
    position: fixed;
    top: 70px;
    left: 0;
    width: 100%;
    background: white;
    flex-direction: row;
    flex-wrap: wrap;
    padding: 20px 16px 24px;
    gap: 10px 12px;
    box-shadow: var(--shadow-lg);
    transform: translateX(-100%);
    transition: var(--transition);
    justify-content: center;
  }
  
  .nav-links.active {
    transform: translateX(0);
  }

  .nav-links li {
    flex: 0 1 calc(33.333% - 8px);
    display: flex;
    justify-content: center;
  }

  .nav-links a {
    width: 100%;
    text-align: center;
    padding: 10px 12px;
    border-radius: 12px;
    background: rgba(59, 130, 246, 0.08);
    color: var(--text-primary);
  }

  .nav-links a::after {
    display: none;
  }

  .nav-links a:hover {
    transform: translateY(-2px);
    background: rgba(59, 130, 246, 0.15);
    color: var(--primary-color);
  }
  
  .nav-cta {
    display: none;
  }
  
  .mobile-menu-btn {
    display: flex;
  }
  
  .section-header h2 {
    font-size: 32px;
  }
  
  .section-header p {
    font-size: 16px;
  }
}