//centering popup
function centerPopup(formID)
{
    //request data for centering
    formID = formID ? formID : '#feedback';
    var centerCoords = getCenterCoords($(formID).find('.aqLayer'));

    $(formID).css({
        position: "absolute", //fixed, absolute, inherit, static
        top: centerCoords.top,
        left : centerCoords.left
    });

    //only need force for IE6
    $("#backgroundPopup").css({   height: document.documentElement.clientHeight });
}

function getCenterCoords(jqObj)
{
    var windowWidth = document.documentElement.clientWidth;
    var windowHeight = document.documentElement.clientHeight;

    var scrollTop = document.documentElement.scrollTop;

    var popupHeight = jqObj.height();
    var popupWidth = jqObj.width();

    var topCoord = scrollTop + windowHeight/2 - popupHeight/2;
    var leftCoord = windowWidth/2 - popupWidth/2;

    return {left: leftCoord, top: topCoord};
}

function clikHide(evt, formID)
{
    var srcObj = evt.srcElement || evt.target;
    if(!isChild(srcObj, document.getElementById(formID)))
        $('#' + formID).aqLayer('hide');
};

function isChild(element, parent)
{
    while(element != null && element != parent)
    {
        element = element.parentNode;
    }
    return element == parent;
}