/* NOTE: requre: jquery.js */ 

function showPopupBox(popupWrap_id, popupBg_id, topVal){

    topVal = topVal || 60;

    var objWrap = jQuery('#'+popupWrap_id);
    objWrap.css("top", (document.documentElement.scrollTop || document.body.scrollTop) + topVal + "px");
/*
    jQuery(window).scroll(function(){
        objWrap.css("top", document.documentElement.scrollTop + topVal + "px");
    });
*/

    var bg = document.getElementById(popupBg_id);
    maskScreen(bg);
    var wrap = document.getElementById(popupWrap_id);
    if(bg.style.display == "none"){
        bg.style.display = "block";
        wrap.style.display = "block";
    }
    else{
        bg.style.display = "none";
        wrap.style.display = "none";;
    }
}

function maskScreen(element) {
        document.body.style.height="100%";
        var scrollW=Math.max(document.body.scrollWidth,document.documentElement.scrollWidth);
        var scrollH=Math.max(document.body.scrollHeight,document.documentElement.scrollHeight);
        scrollH=Math.max(scrollH,Math.max(document.body.clientHeight,document.documentElement.clientHeight));
        if(element.tagName.toLowerCase()=='iframe')
        {
            element.width=scrollW+"px";
            element.height=scrollH+"px";
        }
        else
        {
            element.style.width=scrollW+"px";
            element.style.height=scrollH+"px";
        }

        element.style.position="absolute";
        element.style.top=0;
        element.style.left=0;
        element.style.opacity=0.6;
        element.style.filter='alpha(opacity=60)';
        
        return element;
}