Unable to resize submit button

I am in theme designer and I cannot resize the submit button to fit the layout no matter what size I input. (Screenshot attached)

Also is there a way to reduce the vertical spacing between objects to get rid of blank space?

Regards, Paul

Hello Paul,

Adding to Syed's answer on how to position the submit button I will help show you how to control the vertical spacing and line spacing in your form.

In the theme designer under the Design tab you have the options for line spacing and vertical padding. Both of these options are configurable to allow you to set your own spacing between text and form elements. 

Thanks, Aaron