Opt-in Div Area Resizing

I just had someone customize my theme so I could have a full width header and opt-in below it. For some reason the opt-in area keeps moving on screen zoom, or if you open the page without the browser window open fully. On cell phones this div bar is completely messed up. The opt-in shows below where it should be. I want it to be fixed to that the opt-in info stays within the green area at all times. Hope this makes sense. Myself and my developer are stumped. Any help is greatly appreciated. Thanks!

http://www.arinaura.com is the website