:root {
    --primary-color: #0d47a1;
    --secondary-color: #8e24aa;
    --accent-color: #ff5722;
    --text-color: #ffffff;
    --bg-gradient: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    --card-bg: rgba(255, 255, 255, 0.1);
    --transition: all 0.4s cubic-bezier(0.25, 0.8, 0.25, 1);
  }

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

  body {
    background: var(--bg-gradient);
    color: var(--text-color);
    font-family: 'Roboto', sans-serif;
    line-height: 1.6;
    min-height: 100%;
    overflow-x: hidden;
  }

  .container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
  }

  .header {
    text-align: center;
    padding: 3rem 0;
    position: relative;
    overflow: hidden;
  }

  .header::before {
    content: "";
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
    animation: pulse 15s infinite linear;
    z-index: -1;
  }

  @keyframes pulse {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
  }

  h1, h2, h3, h4 {
    font-weight: 700;
    margin-bottom: 1.5rem;
    line-height: 1.3;
  }

  h1 {
    font-size: 2.5rem;
    background: linear-gradient(90deg, #fff, #81c784);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 1rem;
  }

  h2 {
    font-size: 2rem;
    position: relative;
    padding-bottom: 1rem;
    margin-top: 3rem;
  }

  h2::after {
    content: "";
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100px;
    height: 4px;
    background: linear-gradient(90deg, var(--accent-color), transparent);
    border-radius: 2px;
  }

  h3 {
    font-size: 1.5rem;
    margin-top: 2rem;
    color: #81c784;
  }

  h4 {
    font-size: 1.2rem;
    margin-top: 1.5rem;
    color: #ff9800;
  }

  p {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
  }

  .grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin: 3rem 0;
  }

  .card {
    background: var(--card-bg);
    border-radius: 12px;
    padding: 2rem;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
    backdrop-filter: blur(8px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: var(--transition);
  }

  .card:hover {
    transform: translateY(-10px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.3);
  }

  .img-container {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 1rem;
    margin: 2rem 0;
  }

  .decor-img {
    width: 150px;
    height: 150px;
    border-radius: 12px;
    object-fit: cover;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    transition: var(--transition);
  }

  .decor-img:hover {
    transform: scale(1.05);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.4);
  }

  pre {
    background: rgba(0, 0, 0, 0.3);
    border-radius: 8px;
    padding: 1.5rem;
    overflow: auto;
    margin: 2rem 0;
    border-left: 4px solid var(--accent-color);
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
    line-height: 1.5;
  }

  code {
    color: #81c784;
    font-family: 'Courier New', monospace;
  }

  .note {
    background: rgba(255, 152, 0, 0.1);
    border-left: 4px solid var(--accent-color);
    padding: 1rem;
    margin: 2rem 0;
    border-radius: 0 8px 8px 0;
  }

  .note::before {
    content: "设计提示";
    display: block;
    font-weight: bold;
    margin-bottom: 0.5rem;
    color: var(--accent-color);
  }

  .nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: rgba(13, 71, 161, 0.9);
    backdrop-filter: blur(10px);
    padding: 1rem 2rem;
    z-index: 1000;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.2);
  }

  .nav-list {
    display: flex;
    justify-content: center;
    list-style: none;
    gap: 2rem;
  }

  .nav-link {
    color: white;
    text-decoration: none;
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    transition: var(--transition);
  }

  .nav-link:hover {
    background: rgba(255, 255, 255, 0.2);
  }

  .footer {
    text-align: center;
    padding: 2rem;
    margin-top: 4rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
  }

  @media (max-width: 768px) {
    .grid {
      grid-template-columns: 1fr;
    }
    
    .nav-list {
      gap: 1rem;
      flex-wrap: wrap;
    }
    
    h1 {
      font-size: 2rem;
    }
    
    h2 {
      font-size: 1.7rem;
    }
  }