Simple Html and CSS changes: Chrome and IE display a unwanted distance to top page.

Hello, it`s again a small job. Please check the attached image ("[login to view URL]"). Job is to detect the error that displays the distance to top at Chrome and IE. Job is too to find a solution for this problem. Job is to tell me, what code has to be insert at a file. If you can solve this as it should, i can hire you for many other small jobs. It's about the unwanted distance above the green highlighted area: Visit the website: in the upper interval the distance at Chrome and Internet Explorer is higher (height) than at Firefox browser. With Firefox no unwanted distance upwards is visible. I have attached a picture that explains it better. The green area is a "padding" for the body_content content. That works fine. The padding is needed to start the content after the "header (wrapper_topa)" Above the padding area but is still a distance .. this distance in Chrome and IE I can not explain. Also strange: The logo seems not to be affected by the distance in Chrome. Find a solution that works for IE, CHrome and Firefox. At the end the page has to be as Firefox shows at this moment. Please check if you are able to find the solution BEFORE you make an offer for this job. If you visit an other page than the home page, the distance is gone. So i attached the [login to view URL] too.