function resizeScreenElements(lastcontentheight){

    var contentheight = parseInt(document.getElementById('prb_content').offsetHeight);

    if(lastcontentheight != contentheight){

        if(document.getElementById('prb_content').offsetWidth < 985){
            document.body.style.width = '985px';
        }
        
        var displayheight;
        if(window.innerHeight) //All normal browsers
            displayheight = parseInt(window.innerHeight);
        else //IE
            displayheight = parseInt(document.documentElement.offsetHeight) - 4;
        //alert (displayheight);
        if(displayheight < (65+294+129)) displayheight = 65+294+129;

        if(contentheight < (displayheight - 65 - 129)) {
            document.getElementById('prb_left').style.height = displayheight - 53 - 65 - 129 + "px";
            document.getElementById('prb_right').style.height = displayheight - 65 - 129 + 'px';
        } else {
            document.getElementById('prb_left').style.height = contentheight - 53 + "px";
            document.getElementById('prb_right').style.height = contentheight + 'px';
        }

        resizeScreenElements(contentheight);
    }
}

function pageLoad(){
    resizeScreenElements(0);
    document.getElementById('prb_loading').style.visibility = 'hidden';
    document.getElementById('prb_main').style.visibility = 'visible';
}

function changeMenuButton(e){
    var sourceelement;
    if (e.srcElement) sourceelement = e.srcElement;
    else sourceelement = e.target;
    if (sourceelement.src.search("_akt.gif") > -1) sourceelement.src = sourceelement.src.replace(/_akt.gif/,".gif");
    else sourceelement.src = sourceelement.src.replace(/.gif/,"_akt.gif");
}