Math Captcha Being split by form field

Hi,

My input form fields are set to 100% width. I don’t really want to change the css for the form as it works well for the rest of the form. Right now the input field can be in the middle on a separate line of the question so it looks weird and confusing. for example:

A Little bit of Math
[form field]
+ 2 = 7

or

A Little bit of Math 2 –
[form field]
= 7

so the question is how do I make a css statement specifically shortening this field without compromising the rest of the form. I am using contact form 7 too.