function changeMenu(option){
        if (document.getElementById(option).style.display == "block") {
            document.getElementById(option).style.display="";
            }
        else if (document.getElementById(option).style.display == "") {
            document.getElementById(option).style.display="block";
            }
}
function showHint(part) {
    document.getElementById(part).style.display="block";        
}
function hideHint(part) {
    document.getElementById(part).style.display="";   
}
function closeHelp(part) {
    document.getElementById(part).style.display="";
}
function nextBox(current, next, max) {
     if(document.getElementById(current).value.length >= max)
        document.getElementById(next).focus();
}