Horizontal image align CSS

I’m having some trouble aligning a main image. It should be center-aligned horizontally, yet keeps going all over the place. The page can be found here http://0034.eu/propmanager/

That’s basically the CSS I have applied to the image, all the source code is on main index.html (no separate style sheet).

Thanks!

Add this to your CSS style.

EDIT

From the inputs of IlyaStreltsyn, I agree with the point of clearing the right with display:block for the image to be centered.

For Instance,