body {
    font-family: Arial, sans-serif;
    background-color: greenyellow;
  }
  
  h1 {
    text-align: center;
  }
  
  #todo-container {
    max-width: 400px;
    margin: 20px auto;
    padding: 10px;
    border: 2px solid black;
    border-radius: 5px;
    height: 200px;
    
  }
  
  input[type="text"] {
    width: 100%;
    padding: 5px;
    margin-bottom: 10px;
  }
  
  button {
    padding: 5px 10px;
  }
  
  ul {
    list-style-type: none;
    padding: 0;
  }
  
  li {
    margin-bottom: 5px;
    display: flex;
    align-items: center;
  }
  
  li input[type="checkbox"] {
    margin-right: 10px;
  }