Help with fitting logo to other resolutions

[znightmare]

So I made my logo to fit the resolution that I use (1366x768), it fits perfectly at that resolution but it get all messed up on any other screen resolution. The way I put my banner on my site was to just add a picture to the very top of the header template, so is there a code I can use before the picture to make it expand or get smaller depending on the resolution?

Here's a pic of it on 1440x900


my url is http://anime-forum.net