How to customize the Look & Feel of the form

In the Form:General page, Look & Feel tab select the 'custom' option

Press 'Next' and in the Look and Feel Page you can edit and customize the style of the form

You can load pre-built styles pressing the Load Style button. Similarly, you can save your custom style and apply it to your other forms.

You can use the custom CSS button to further customize the style using CSS code.