Mobile Friendly Forms

I want users to be able and fill in my form on their mobile devices. What's the best and easiest way to make my form "mobile" friendly?

They are already relatively mobile friendly via the form's direct url. However, to get it to display better via a mobile device screen it has to be customized further using css codes that are injected into your form. 

An example of this to direct your css only at a mobile device would start with the following:

/* Smartphones (portrait and landscape) ----------- */@media only screen and (min-device-width : 320px) and (max-device-width : 480px) {/* Styles */}