     display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .preview {
      flex: 1;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    textarea {
      width: 100%;
      height: 400px;
      font-family: monospace;
      padding: 10px;
      border: 1px solid #ccc;
      border-radius: 4px;
      resize: vertical;
    }

    iframe {
      width: 100%;
      height: 400px;
      border: 1px solid #ccc;
      border-radius: 4px;
    }

    .controls {
      di