function disappear (stl)
{
	stl.style.visibility="hidden";
}
function reappear (stl)
{
	stl.style.visibility="visible";
}

function realPosition (elId, mstl, LP, TP)
{
	mstl.style.left=getLeftPosition(elId, LP);
	mstl.style.top=getTopPosition(elId, TP);
}

function getLeftPosition(elemID, LP) {
    var offsetTrail = document.getElementById(elemID);
    var offsetLeft = 0;
    while (offsetTrail) {
        offsetLeft += offsetTrail.offsetLeft;
        offsetTrail = offsetTrail.offsetParent;
    }
    if (navigator.userAgent.indexOf("Mac") != -1 && 
        typeof document.body.leftMargin != "undefined") {
        offsetLeft += document.body.leftMargin;
    }
    return offsetLeft+LP;
}
function getTopPosition(elemID, TP) {
    var offsetTrail = document.getElementById(elemID);
    var offsetTop = 0;
    while (offsetTrail) {
        offsetTop += offsetTrail.offsetTop;
        offsetTrail = offsetTrail.offsetParent;
    }
    if (navigator.userAgent.indexOf("Mac") != -1 && 
        typeof document.body.leftMargin != "undefined") {
        offsetTop += document.body.topMargin;
    }
    return offsetTop+TP;
}