/* 核聚变门户网站样式 */
:root {
  --primary-color: #0066cc;
  --secondary-color: #ff6b35;
  --accent-color: #00d4aa;
  --dark-bg: #1a1a2e;
  --darker-bg: #16213e;
  --light-bg: #f8f9fa;
  --text-primary: #333;
  --text-secondary: #666;
  --text-light: #ffffff;
  --border-color: #e0e0e0;
  --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  --shadow-hover: 0 8px 25px rgba(0, 0, 0, 0.15);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  line-height: 1.6;
  color: var(--text-primary);
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
}

/* 头部导航 */
.header {
  background: rgba(26, 26, 46, 0.95);
  backdrop-filter: blur(10px);
  position: fixed;
  top: 0;
  width: 100%;
  z-index: 1000;
  padding: 1rem 0;
  box-shadow: var(--shadow);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0 2rem;
}

.logo {
  font-size: 1.8rem;
  font-weight: bold;
  color: var(--accent-color);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.logo::before {
  content: "⚛️";
  font-size: 2rem;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: 2rem;
}

.nav-menu a {
  color: var(--text-light);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s ease;
  position: relative;
}

.nav-menu a:hover {
  color: var(--accent-color);
}

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

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

/* 主要内容区域 */
.main-content {
  margin-top: 80px;
  min-height: calc(100vh - 80px);
}

/* 英雄区域 */
.hero {
  background: linear-gradient(rgba(26, 26, 46, 0.8), rgba(22, 33, 62, 0.8)),
              url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1000 1000"><defs><radialGradient id="a" cx="50%" cy="50%"><stop offset="0%" stop-color="%2300d4aa" stop-opacity="0.1"/><stop offset="100%" stop-color="%230066cc" stop-opacity="0.05"/></radialGradient></defs><rect width="100%" height="100%" fill="url(%23a)"/></svg>');
  background-size: cover;
  background-position: center;
  padding: 6rem 2rem;
  text-align: center;
  color: var(--text-light);
}

.hero h1 {
  font-size: 3.5rem;
  margin-bottom: 1rem;
  background: linear-gradient(45deg, var(--accent-color), var(--primary-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero p {
  font-size: 1.3rem;
  margin-bottom: 2rem;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
  opacity: 0.9;
}

.cta-button {
  display: inline-block;
  background: linear-gradient(45deg, var(--primary-color), var(--accent-color));
  color: white;
  padding: 1rem 2rem;
  text-decoration: none;
  border-radius: 50px;
  font-weight: bold;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  box-shadow: var(--shadow);
}

.cta-button:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-hover);
}

/* 模块网格 */
.modules-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
  gap: 2rem;
  padding: 4rem 2rem;
  max-width: 1200px;
  margin: 0 auto;
}

.module-card {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-radius: 15px;
  padding: 2rem;
  box-shadow: var(--shadow);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.module-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-hover);
}

.module-card h3 {
  color: var(--primary-color);
  margin-bottom: 1rem;
  font-size: 1.5rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.module-card p {
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  line-height: 1.7;
}

.module-link {
  color: var(--primary-color);
  text-decoration: none;
  font-weight: bold;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  transition: color 0.3s ease;
}

.module-link:hover {
  color: var(--secondary-color);
}

.module-link::after {
  content: "→";
  transition: transform 0.3s ease;
}

.module-link:hover::after {
  transform: translateX(5px);
}

/* 内容页面样式 */
.content-page {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  margin: 2rem;
  border-radius: 15px;
  padding: 3rem;
  box-shadow: var(--shadow);
  max-width: 1200px;
  margin: 2rem auto;
}

.content-page h1 {
  color: var(--primary-color);
  margin-bottom: 2rem;
  font-size: 2.5rem;
  text-align: center;
}

.content-page h2 {
  color: var(--primary-color);
  margin: 2rem 0 1rem 0;
  font-size: 1.8rem;
  border-bottom: 2px solid var(--accent-color);
  padding-bottom: 0.5rem;
}

.content-page h3 {
  color: var(--text-primary);
  margin: 1.5rem 0 1rem 0;
  font-size: 1.3rem;
}

.content-page p {
  margin-bottom: 1rem;
  line-height: 1.8;
  text-align: justify;
}

.content-page ul, .content-page ol {
  margin: 1rem 0 1rem 2rem;
}

.content-page li {
  margin-bottom: 0.5rem;
  line-height: 1.6;
}

/* 时间线样式 */
.timeline {
  position: relative;
  padding: 2rem 0;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 50%;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--accent-color);
  transform: translateX(-50%);
}

.timeline-item {
  position: relative;
  margin: 2rem 0;
  display: flex;
  align-items: center;
}

.timeline-item:nth-child(odd) {
  flex-direction: row-reverse;
}

.timeline-content {
  background: rgba(255, 255, 255, 0.9);
  padding: 1.5rem;
  border-radius: 10px;
  box-shadow: var(--shadow);
  width: 45%;
  margin: 0 2rem;
}

.timeline-year {
  background: var(--primary-color);
  color: white;
  padding: 0.5rem 1rem;
  border-radius: 20px;
  font-weight: bold;
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  z-index: 10;
}

/* 论文卡片 */
.paper-card {
  background: rgba(255, 255, 255, 0.9);
  border-radius: 10px;
  padding: 1.5rem;
  margin: 1rem 0;
  box-shadow: var(--shadow);
  transition: transform 0.3s ease;
}

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

.paper-title {
  color: var(--primary-color);
  font-weight: bold;
  margin-bottom: 0.5rem;
}

.paper-authors {
  color: var(--text-secondary);
  font-style: italic;
  margin-bottom: 0.5rem;
}

.paper-journal {
  color: var(--text-secondary);
  font-size: 0.9rem;
}

/* 技术路线对比表 */
.tech-comparison {
  overflow-x: auto;
  margin: 2rem 0;
}

.tech-table {
  width: 100%;
  border-collapse: collapse;
  background: rgba(255, 255, 255, 0.9);
  border-radius: 10px;
  overflow: hidden;
  box-shadow: var(--shadow);
}

.tech-table th {
  background: var(--primary-color);
  color: white;
  padding: 1rem;
  text-align: left;
}

.tech-table td {
  padding: 1rem;
  border-bottom: 1px solid var(--border-color);
}

.tech-table tr:hover {
  background: rgba(0, 212, 170, 0.1);
}

/* 公司卡片 */
.company-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin: 2rem 0;
}

.company-card {
  background: rgba(255, 255, 255, 0.9);
  border-radius: 10px;
  padding: 2rem;
  box-shadow: var(--shadow);
  transition: transform 0.3s ease;
}

.company-card:hover {
  transform: translateY(-3px);
}

.company-name {
  color: var(--primary-color);
  font-size: 1.3rem;
  font-weight: bold;
  margin-bottom: 1rem;
}

/* 导航链接网格 */
.links-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1.5rem;
  margin: 2rem 0;
}

.link-card {
  background: rgba(255, 255, 255, 0.9);
  border-radius: 10px;
  padding: 1.5rem;
  box-shadow: var(--shadow);
  transition: transform 0.3s ease;
  text-decoration: none;
  color: inherit;
}

.link-card:hover {
  transform: translateY(-2px);
  text-decoration: none;
}

.link-title {
  color: var(--primary-color);
  font-weight: bold;
  margin-bottom: 0.5rem;
}

.link-description {
  color: var(--text-secondary);
  font-size: 0.9rem;
}

/* 返回按钮 */
.back-button {
  display: inline-block;
  background: var(--primary-color);
  color: white;
  padding: 0.8rem 1.5rem;
  text-decoration: none;
  border-radius: 25px;
  margin-bottom: 2rem;
  transition: background 0.3s ease;
}

.back-button:hover {
  background: var(--secondary-color);
}

/* 响应式设计 */
@media (max-width: 768px) {
  .nav-menu {
    display: none;
  }
  
  .hero h1 {
    font-size: 2.5rem;
  }
  
  .hero p {
    font-size: 1.1rem;
  }
  
  .modules-grid {
    grid-template-columns: 1fr;
    padding: 2rem 1rem;
  }
  
  .content-page {
    margin: 1rem;
    padding: 2rem 1.5rem;
  }
  
  .timeline::before {
    left: 20px;
  }
  
  .timeline-item {
    flex-direction: column;
    align-items: flex-start;
    padding-left: 50px;
  }
  
  .timeline-content {
    width: 100%;
    margin: 0;
  }
  
  .timeline-year {
    left: 20px;
    transform: none;
  }
}

/* 动画效果 */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.module-card {
  animation: fadeInUp 0.6s ease forwards;
}

.module-card:nth-child(1) { animation-delay: 0.1s; }
.module-card:nth-child(2) { animation-delay: 0.2s; }
.module-card:nth-child(3) { animation-delay: 0.3s; }
.module-card:nth-child(4) { animation-delay: 0.4s; }
.module-card:nth-child(5) { animation-delay: 0.5s; }
.module-card:nth-child(6) { animation-delay: 0.6s; }
.module-card:nth-child(7) { animation-delay: 0.7s; }

/* 滚动条样式 */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: rgba(255, 255, 255, 0.1);
}

::-webkit-scrollbar-thumb {
  background: var(--accent-color);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--primary-color);
}