Image instead of Checkbox/RadioButton

Hi, i use gravity form for email, and i apreciate most the animation that is enabled when a logical condition is met. For instance, if i use a drop-down named "Contact an agent?", with the two option "yes" and "no", upon selecting the "yes" option, the email will appear in the same page.

What i want is an image that function the same as a checkbox or dropdown instead of them itself. Once press the button for "yes" and another for "no", instead of selecting the options.

I can't explain well what i want, then i will show you, here the link of my site. I modified with css the checkboxes selection, that i don't use in the site itself, and i transformed it to a button image.
The button is "Contatta un agente", it's the same in all the post, and once clicked, will appear a drop down menù and a email in which the subject is populated with the number id and the title of the post, depending in which post are the gravity form.

http://tizianogiannotta.it/elegantestate/2012/05/07/in-aria-aperta/

Is it possibile to have that simple feature without editing each time the style.css? Thanks

I know that's an animation that can be created from css and php/jquery, but it's simple that the gravity form already support that for opening the fields if the logical condition is meet, and then without editing the css each time, i only wanted to use a button from the gravity form back panel as a "field" such the checkbobex or radio buttons and in the css i have to edit only the background image for the button itself without editing the rest of the code.

However, can you tell me if it's simple to clone the function "verify checkbox" of gravity form, rename it to "button", and i can modify it via css. Is it possible? If so which php files i have to watch, or i have to wait for that feature?
Thanks again.

Thank you, but i simple wanted to convert checkbox and the label in one complete button wrapping it all. For that i did edit the css, converting a checkbox to an image button, without losing the use for the conditional logic on modules of gravity form. The above link was the result. Simple i wanted to use it as a feature to activate the modules, instead of them to be open right at the start on the post, and since they are using animated jquery itself, i didn't want to go edit again each time the css, but to use them right away. Mine was only a toughts for the future releases. :)