var nImage = 2;

function toggleBackground()
{

	var sBack = '';

	if ( nImage == 1 ) {
		nImage = 2;
		sBack = 'url("images/oo/gfx_background_2.jpg") no-repeat center right';

	} else {
		nImage = 1;
		sBack = 'url("images/oo/gfx_background_1.jpg") no-repeat center right';
	}

	if ( document.getElementById('corp_gfx') ) {
	  document.getElementById('corp_gfx').style.background = sBack;
	}
}