Width of form fields

Hi

Fields of my forms are getting very close, not properly filling the entire column. Want them to stay with the full width of the column. How do I?

Here is a sample page using the form: http://vivoconfeccoes.com.br/produtos-copa-2014/

Here an example of how I want you (subject field):
http://kriesi.at/themes/enfold/pages/contact/

thanks