/* 全新革命性教育网站样式表 */
/* 采用极简主义设计，深色主题，霓虹效果 */

:root {
  /* 深色主题色彩 */
  --dark-bg: #0f0f1a;
  --darker-bg: #0a0a12;
  --card-bg: #1a1a2e;
  --accent-primary: #00f7ff;
  --accent-secondary: #ff00c8;
  --accent-tertiary: #7a00ff;
  --text-primary: #e0e0ff;
  --text-secondary: #a0a0c0;
  --success: #00ff9d;
  --warning: #ffcc00;
  --danger: #ff3860;
  
  /* 渐变 */
  --gradient-neon: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary), var(--accent-tertiary));
  --gradient-card: linear-gradient(145deg, var(--card-bg), #252540);
  
  /* 阴影 */
  --neon-shadow-primary: 0 0 10px var(--accent-primary), 0 0 20px rgba(0, 247, 255, 0.3);
  --neon-shadow-secondary: 0 0 10px var(--accent-secondary), 0 0 20px rgba(255, 0, 200, 0.3);
  --neon-shadow-tertiary: 0 0 10px var(--accent-tertiary), 0 0 20px rgba(122, 0, 255, 0.3);
  
  /* 圆角 */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 50%;
  
  /* 间距 */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 32px;
  --space-xxl: 48px;
  --space-xxxl: 64px;
  
  /* 字体 */
  --font-primary: 'Segoe UI', 'Roboto', 'Helvetica Neue', sans-serif;
  --font-mono: 'Fira Code', 'Monaco', 'Consolas', monospace;
  
  /* 断点 */
  --breakpoint-sm: 576px;
  --breakpoint-md: 768px;
  --breakpoint-lg: 992px;
  --breakpoint-xl: 1200px;
}

/* 基础重置 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-primary);
  background-color: var(--dark-bg);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
}

/* 容器 */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-md);
}

/* 网格系统 */
.grid {
  display: grid;
  gap: var(--space-lg);
}

.grid-cols-1 { grid-template-columns: 1fr; }
.grid-cols-2 { grid-template-columns: repeat(2, 1fr); }
.grid-cols-3 { grid-template-columns: repeat(3, 1fr); }
.grid-cols-4 { grid-template-columns: repeat(4, 1fr); }

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-sm) var(--space-lg);
  border-radius: var(--radius-md);
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  border: none;
  text-decoration: none;
  font-size: 1rem;
}

.btn-primary {
  background: var(--gradient-neon);
  color: var(--darker-bg);
  box-shadow: var(--neon-shadow-primary);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 20px var(--accent-primary), 0 0 30px rgba(0, 247, 255, 0.5);
}

.btn-secondary {
  background: transparent;
  color: var(--accent-primary);
  border: 1px solid var(--accent-primary);
  box-shadow: var(--neon-shadow-primary);
}

.btn-secondary:hover {
  background: rgba(0, 247, 255, 0.1);
  transform: translateY(-2px);
}

.btn-lg {
  padding: var(--space-md) var(--space-xl);
  font-size: 1.125rem;
}

/* 卡片 */
.card {
  background: var(--gradient-card);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
  transition: all 0.3s ease;
  border: 1px solid rgba(255, 255, 255, 0.05);
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.4);
}

.card-neon {
  position: relative;
  overflow: hidden;
}

.card-neon::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  border-radius: var(--radius-lg);
  padding: 1px;
  background: var(--gradient-neon);
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: destination-out;
  mask-composite: exclude;
  pointer-events: none;
  z-index: 1;
}

/* 标题 */
.section-title {
  font-size: 2.5rem;
  font-weight: 800;
  text-align: center;
  margin-bottom: var(--space-xl);
  background: var(--gradient-neon);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  position: relative;
}

.section-title::after {
  content: '';
  display: block;
  width: 100px;
  height: 4px;
  background: var(--gradient-neon);
  margin: var(--space-md) auto 0;
  border-radius: 2px;
}

.section-subtitle {
  font-size: 1.25rem;
  text-align: center;
  color: var(--text-secondary);
  max-width: 700px;
  margin: 0 auto var(--space-xxl);
}

/* 导航 */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background: rgba(10, 10, 18, 0.9);
  backdrop-filter: blur(10px);
  padding: var(--space-md) 0;
  z-index: 1000;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-logo {
  font-size: 1.75rem;
  font-weight: 800;
  background: var(--gradient-neon);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  text-decoration: none;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: var(--space-lg);
}

.nav-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
  transition: all 0.3s ease;
  position: relative;
}

.nav-link:hover {
  color: var(--accent-primary);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient-neon);
  transition: width 0.3s ease;
}

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

.nav-toggle {
  display: none;
  flex-direction: column;
  cursor: pointer;
}

.nav-toggle span {
  width: 25px;
  height: 3px;
  background: var(--accent-primary);
  margin: 3px 0;
  transition: 0.3s;
}

/* 英雄区域 */
.hero {
  padding: 150px 0 100px;
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle, rgba(0, 247, 255, 0.05) 0%, transparent 70%);
  z-index: -1;
}

.hero-content {
  max-width: 700px;
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 900;
  line-height: 1.2;
  margin-bottom: var(--space-lg);
  background: var(--gradient-neon);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.5rem;
  color: var(--text-secondary);
  margin-bottom: var(--space-xl);
  line-height: 1.6;
}

.hero-buttons {
  display: flex;
  gap: var(--space-md);
}

/* 特性区域 */
.features {
  padding: 100px 0;
  background: var(--darker-bg);
}

.features-grid {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.feature-card {
  text-align: center;
  padding: var(--space-xl);
}

.feature-icon {
  width: 80px;
  height: 80px;
  margin: 0 auto var(--space-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 247, 255, 0.1);
  border-radius: var(--radius-full);
  font-size: 2rem;
  color: var(--accent-primary);
  box-shadow: var(--neon-shadow-primary);
}

.feature-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: var(--space-md);
  color: var(--text-primary);
}

.feature-description {
  color: var(--text-secondary);
  line-height: 1.7;
}

/* 课程区域 */
.courses {
  padding: 100px 0;
}

.courses-grid {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.course-card {
  padding: var(--space-xl);
  position: relative;
  overflow: hidden;
}

.course-icon {
  font-size: 3rem;
  margin-bottom: var(--space-lg);
  background: var(--gradient-neon);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.course-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: var(--space-md);
  color: var(--text-primary);
}

.course-description {
  color: var(--text-secondary);
  margin-bottom: var(--space-lg);
  line-height: 1.7;
}

/* CTA区域 */
.cta {
  padding: 100px 0;
  background: var(--darker-bg);
  text-align: center;
}

.cta-content {
  max-width: 700px;
  margin: 0 auto;
}

.cta-title {
  font-size: 2.5rem;
  font-weight: 800;
  margin-bottom: var(--space-lg);
  background: var(--gradient-neon);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.cta-description {
  font-size: 1.25rem;
  color: var(--text-secondary);
  margin-bottom: var(--space-xl);
  line-height: 1.7;
}

/* 页脚 */
.footer {
  background: var(--darker-bg);
  padding: 80px 0 40px;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
}

.footer-grid {
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--space-xl);
  margin-bottom: var(--space-xxl);
}

.footer-column h3 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: var(--space-lg);
  color: var(--text-primary);
  background: var(--gradient-neon);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.footer-column ul {
  list-style: none;
}

.footer-column li {
  margin-bottom: var(--space-sm);
}

.footer-column a {
  color: var(--text-secondary);
  text-decoration: none;
  transition: all 0.3s ease;
}

.footer-column a:hover {
  color: var(--accent-primary);
  padding-left: 5px;
}

.footer-bottom {
  text-align: center;
  padding-top: var(--space-lg);
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  color: var(--text-secondary);
  font-size: 0.875rem;
}

/* 动画 */
@keyframes float {
  0% { transform: translateY(0px); }
  50% { transform: translateY(-20px); }
  100% { transform: translateY(0px); }
}

@keyframes pulse {
  0% { box-shadow: 0 0 0 0 rgba(0, 247, 255, 0.7); }
  70% { box-shadow: 0 0 0 15px rgba(0, 247, 255, 0); }
  100% { box-shadow: 0 0 0 0 rgba(0, 247, 255, 0); }
}

.float-animation {
  animation: float 6s ease-in-out infinite;
}

.pulse-animation {
  animation: pulse 2s infinite;
}

/* 响应式设计 */
@media (max-width: 992px) {
  .hero-title {
    font-size: 3rem;
  }
  
  .section-title {
    font-size: 2rem;
  }
}

@media (max-width: 768px) {
  .nav-menu {
    position: fixed;
    left: -100%;
    top: 70px;
    flex-direction: column;
    background: var(--darker-bg);
    width: 100%;
    text-align: center;
    transition: 0.3s;
    box-shadow: 0 10px 27px rgba(0, 0, 0, 0.05);
    padding: var(--space-lg) 0;
  }
  
  .nav-menu.active {
    left: 0;
  }
  
  .nav-toggle {
    display: flex;
  }
  
  .hero {
    padding: 120px 0 80px;
  }
  
  .hero-title {
    font-size: 2.5rem;
  }
  
  .hero-subtitle {
    font-size: 1.25rem;
  }
  
  .hero-buttons {
    flex-direction: column;
    gap: var(--space-sm);
  }
  
  .section-title {
    font-size: 1.75rem;
  }
  
  .features-grid,
  .courses-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 576px) {
  .container {
    padding: 0 var(--space-sm);
  }
  
  .hero-title {
    font-size: 2rem;
  }
  
  .section-title {
    font-size: 1.5rem;
  }
  
  .card {
    padding: var(--space-md);
  }
}