body {
      background-color: black;
      color: lime;
      font-family: "Courier New", monospace;
      margin: 0;
      padding: 0;
      overflow: hidden;
    }
    #code-area {
      width: 100%;
      height: 100vh;
      display: flex;
      align-items: flex-start;
      justify-content: flex-start;
      flex-direction: column;
      padding: 20px;
      box-sizing: border-box;
      white-space: pre;
      overflow-y: scroll;
    }
    #code-area::selection {
      background-color: #00FF00;
    }
    #code-area[contenteditable="true"]:empty::before {
      content: attr(placeholder);
      color: gray;
    }
    #code-area:focus {
      outline: none;
    }