How can I change the width and height of the upload?

Height

You can configure the upload field height in the app on the Upload field > Themes section:

The min height setting will configure the initial height:

Max height:  this setting only applies if the upload field is configured to allow multiple uploads.  As soon as the max height is reached, a scrollbar will appear.

Width

The upload field always fits itself in the parent element.

To change the width of the upload field you can reduce the size of the element where the upload widget is displayed.

If you use a custom div container, just add a max-width style to it:

<div class="upload-lift" style="max-width:300px;"></div>

If you need further assistance, please send us a request and we will be happy to help you out.