Recently we began to look again at cross-browser compatibility.

Our site http://www.safariquip.co.uk looks fine in basically all versions of Internet Explorer.

The problem comes with Netscape and Opera.

In Opera, there is a white border around the whole page, for reasons unknown. Does anyone know why this is there?

There are other problems with the two browsers, but this is the main one. Can anybody shed any light on it? Solutions?

Anyone with any other solutions to the numerous problems that are visible, please let me know

Much Obliged

Its because topmargin, leftmargin, marginwidth, and marginheight aren't actually "valid" html. If you add this to the head of the page it should take away the white border:

<style type="text/css">
body { padding:0; margin:0; }
</style>

Good luck and great new design.
-dk