Form Type: Select Defaults or Custom. 
MailChimp Sign-Up Form: Choose the MailChimp form from the list.

Form:

Border Widget: Set the thickness of the border around the form.
Border Radius: Set the border radius for the form to control corner roundness.
Padding: Set the inner spacing between the edge of the form and the edge of container.
Margin: Set the outer spacing between the edge of the form and the edge of the item container.
Form Height: Set the exact height of the slide in either PX, VH, or EM.
Form Width: Set the exact width of the slide in either PX, VH, or EM.
Alignment: Align the form text to the right, left or center.
Background Color: Set the background color of the form.
Border Color: Choose the form border color.
Box Shadow: Give the form a box shadow.

Color: Set the button’s text color.
Background Color: Set the background color of the button.
Border Widget: Set the thickness of the border around the button.
Border Radius: Set the border radius for the button to control corner roundness.
Border Color: Choose the border color.
Button Typography: Customize the typography of the Title.
Margin: Set the outer spacing between the edge of the button and the edge of the container.
Padding: Set the inner spacing between the edge of the button and the edge of the container.