<ol class="tree">
  <li>
    <label>folder0</label>
    <input type="checkbox" />
    <ol>
      <li>
        <label>folder1</label>
        <input type="checkbox" />
        <ol>
          <li>
            <label>folder2</label>
            <input type="checkbox" />
            <ol>
              <li class="file">
                <a href="folder0/folder1/folder2/0"><span class="icon"></span>0</a>
              </li>
            </ol>
          </li>
          <li>
            <label>folder3</label>
            <input type="checkbox" />
            <ol>
              <li class="file">
                <a href="folder0/folder1/folder3/1"><span class="icon"></span>1</a>
              </li>
            </ol>
          </li>
        </ol>
      </li>
    </ol>
  </li>
  <li>
    <label>folder4</label>
    <input type="checkbox" />
    <ol>
      <li class="file">
        <a href="folder4/2"><span class="icon"></span>2</a>
      </li>
    </ol>
  </li>
</ol>
