function opacity(id, opacStart, opacEnd, millisec)
{
var speed = Math.round(millisec / 100);
var timer = 0;
if(opacStart > opacEnd)
{
for(i = opacStart; i >= opacEnd; i--)
{
setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed));
timer++;
}
}
else if(opacStart < opacEnd)
{
for(i = opacStart; i <= opacEnd; i++)
{
setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed));
timer++;
}
}
}

function changeOpac(opacity, id)
{
var object = document.getElementById(id).style;
object.opacity = (opacity / 100);
object.filter = "alpha(opacity=" + opacity + ")";
if(opacity=="0")
{
document.getElementById('opaque').style.display='none';
document.getElementById('ontop').style.display='none';
}
if(opacity=="50")
{
document.getElementById('ontop').style.display='block';
}
}

function openAdvertisment()
{
var documentBodyWidth=document.body.scrollWidth;
var documentBodyHeight=document.body.scrollHeight;
document.getElementById('opaque').style.width=documentBodyWidth+"px";
document.getElementById('opaque').style.height=documentBodyHeight+"px";
document.getElementById('opaque').style.display='block';
document.getElementById('ontop').style.left=(documentBodyWidth / 2 - 300)+"px";
//document.getElementById('ontop').style.display='block';
opacity('opaque',1,50,2000);
}

function closeAdvertisment()
{
opacity('opaque',49,0,2000);
//document.getElementById('opaque').style.display='none';
//document.getElementById('ontop').style.display='none';
}