how to add padding to materialize css input code example

Example: materialize css form file input

<form action="#">
    <div class="file-field input-field">
      <div class="btn">
        <span>File</span>
        <input type="file">
      </div>
      <div class="file-path-wrapper">
        <input class="file-path validate" type="text">
      </div>
    </div>
  </form>