:root {
    --primary-color: #1E275F; /* 深蓝色 */
    --secondary-color: #6F34B8; /* 紫色 */
    --accent-color: #FF6F91; /* 珊瑚橙 */
    --light-color: #FFFFFF;
    --dark-color: #000000;
    --gradient-bg: linear-gradient(135deg, #1E275F, #6F34B8);
    --font-primary: 'Roboto', sans-serif;
    --font-secondary: 'Helvetica', sans-serif;
    --transition-speed: 0.3s;
  }

  body {
    margin: 0;
    padding: 0;
    background: var(--gradient-bg);
    color: var(--light-color);
    font-family: var(--font-primary);
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
  }

  header {
    background: rgba(30, 39, 95, 0.9);
    padding: 20px 40px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: sticky;
    top: 0;
    z-index: 1000;
  }

  header h1 {
    font-size: 2rem;
    color: var(--accent-color);
    text-shadow: 2px 2px 5px rgba(255, 255, 255, 0.3);
  }

  nav a {
    color: var(--light-color);
    margin-left: 20px;
    text-decoration: none;
    transition: color var(--transition-speed);
  }

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

  .container {
    flex: 1;
    padding: 40px 20px;
    max-width: 1200px;
    margin: 0 auto;
  }

  .intro {
    background: rgba(111, 52, 184, 0.8);
    padding: 30px;
    border-radius: 10px;
    margin-bottom: 40px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
  }

  .intro h2 {
    font-size: 2.5rem;
    margin-bottom: 20px;
    color: var(--light-color);
    text-align: center;
    text-shadow: 1px 1px 3px rgba(0,0,0,0.3);
  }

  .intro p {
    font-size: 1.1rem;
    color: var(--light-color);
    text-align: justify;
  }

  article {
    background: rgba(255, 255, 255, 0.05);
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
    margin-bottom: 40px;
  }

  article h2, article h3 {
    font-family: var(--font-primary);
    color: var(--accent-color);
    text-shadow: 1px 1px 3px rgba(0,0,0,0.3);
  }

  article h2 {
    font-size: 2rem;
    margin-bottom: 20px;
  }

  article h3 {
    font-size: 1.5rem;
    margin-top: 30px;
    margin-bottom: 15px;
  }

  article p {
    font-family: var(--font-secondary);
    font-size: 1rem;
    color: var(--light-color);
    margin-bottom: 15px;
    text-align: justify;
  }

  article pre {
    background: rgba(30, 39, 95, 0.9);
    padding: 15px;
    border-radius: 5px;
    overflow-x: auto;
    margin-bottom: 20px;
  }

  article code {
    color: var(--accent-color);
    font-family: 'Courier New', Courier, monospace;
    font-size: 0.95rem;
  }

  table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
  }

  table, th, td {
    border: 1px solid var(--accent-color);
  }

  th, td {
    padding: 10px;
    text-align: left;
    color: var(--light-color);
  }

  th {
    background: rgba(111, 52, 184, 0.7);
  }

  .sample-data {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 20px;
    margin-bottom: 40px;
  }

  .sample-card {
    background: rgba(30, 39, 95, 0.8);
    padding: 20px;
    border-radius: 10px;
    text-align: center;
    transition: transform var(--transition-speed);
  }

  .sample-card:hover {
    transform: scale(1.05);
  }

  .sample-card img {
    width: 100%;
    height: auto;
    border-radius: 5px;
    margin-bottom: 15px;
  }

  .sample-card p {
    color: var(--light-color);
    font-size: 1rem;
  }

  footer {
    background: rgba(30, 39, 95, 0.9);
    text-align: center;
    padding: 20px;
    color: var(--light-color);
    font-size: 0.9rem;
  }

  /* Button styles */
  .btn {
    background: var(--accent-color);
    color: var(--dark-color);
    padding: 10px 20px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: transform var(--transition-speed), background-color var(--transition-speed);
    font-size: 1rem;
  }

  .btn:hover {
    transform: scale(1.1);
    background: #FF3E7E;
  }

  /* Responsive Design */
  @media (max-width: 1440px) {
    header, .container, footer {
      padding: 20px;
    }

    .intro h2 {
      font-size: 2rem;
    }

    article h2 {
      font-size: 1.8rem;
    }

    article h3 {
      font-size: 1.3rem;
    }
  }

  @media (max-width: 1200px) {
    .container {
      padding: 30px 15px;
    }

    .sample-data {
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    }
  }

  @media (max-width: 1024px) {
    header {
      flex-direction: column;
      align-items: flex-start;
    }

    nav {
      margin-top: 10px;
    }
  }

  @media (max-width: 768px) {
    .intro, article {
      padding: 20px;
    }

    .sample-card {
      padding: 15px;
    }
  }

  @media (max-width: 480px) {
    header h1 {
      font-size: 1.5rem;
    }

    .intro h2 {
      font-size: 1.8rem;
    }

    article h2 {
      font-size: 1.5rem;
    }

    article h3 {
      font-size: 1.1rem;
    }

    .btn {
      padding: 8px 16px;
      font-size: 0.9rem;
    }
  }

  @media (max-width: 320px) {
    header, .container, footer {
      padding: 10px;
    }

    .intro h2 {
      font-size: 1.5rem;
    }

    article h2 {
      font-size: 1.3rem;
    }

    article h3 {
      font-size: 1rem;
    }

    .btn {
      padding: 6px 12px;
      font-size: 0.8rem;
    }
  }