If you want to manipulate the positioning of an element, you can make use of the technique known as negative margin:-
By using negative top and left margins, you can move the element upwards and to the left. Conversely, negative right and bottom margins will shift following siblings to the left and up.
Is there a risk of compatibility issues with browsers like IE7,8?
There should be no problems as long as you're working with a modern browser.
Refer to this resource for more information:-
Negative margins are widely supported across all contemporary browsers (and even in some cases, IE6).
As a bonus tip:- Negative margins can prove to be incredibly useful in certain situations, particularly when you need to precisely position a div without resorting to absolute or relative positioning methods.