* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
  }
  
  body {
    font-family: 'Arial', sans-serif;
    background-color: #f4f4f4;
  }
  
  header {
    background-color: #333;
    padding: 20px;
  }
  
  h1 {
    color: white;
    font-size: 24px;
  }
  
  .chart-container {
    width: 100%;
    height: calc(100vh - 60px);
  }
  
  #etf-chart {
    width: 100%;
    height: 100%;
  }
  
  .footer {
    position: fixed;
    bottom: 0;
    right: 0;
    background-color: rgba(128, 128, 128, 0.5);
    padding: 5px 15px;
    font-size: 1rem;
  }