border_width = 0;

x = Math.max(0, ((document.body.clientWidth - W_contenu) / 2));

ns4 = (document.layers)? true:false
ns6 = (document.getElementById && !document.all);
if (!ns4)
{
	document.write('<div id=blanco style="position: absolute;  width: 0; height: 0; border-style: solid; border-width: '+ border_width +'; border-color: #c0c0c0; visibility: hidden"></div>');

	document.write('<div onresize=cadre_ext_on_resize() id=cadre_ext style="position: absolute; left: '+ x +'; top: '+ 0 +';">');
}

if (ns6)
{
	cadre = document.getElementById("cadre_ext");
	cadre_blanc = document.getElementById("blanco");
}
else
{
	cadre = document.all.cadre_ext
	cadre_blanc = document.all.blanco
}

window.onresize = recadrer;
function recadrer()
{
	if (ns6)
		a = document.body.clientWidth - navigator_offset;
	else
		a = document.body.clientWidth;
	cadre.style.left = Math.max(0, ((a - W_contenu) / 2));
	cadre_ext_on_resize();
}

recadrer()

function cadre_ext_on_resize()
{
	if (ns6)
		add = 0;
	else
		add = border_width * 2;
	x = parseInt(cadre.style.left);
	if (x > border_width)
	{
		cadre_blanc.style.left = x - border_width;
		cadre_blanc.style.width =  W_contenu + add;
		cadre_blanc.style.visibility = "visible";
	}
	else 
	{
		cadre_blanc.style.left = 0;
		cadre_blanc.style.width =  0;
		cadre_blanc.style.visibility = "hidden";
	}
}