var i = 1;
function swapDivNext(i) {
    if (document.getElementById("stap" + i).style.display == "block") {
        document.getElementById("stap" + i).style.display = "none";
        x = i + 1;
        document.getElementById("stap" + x).style.display = "block";
    }
}
function swapDivPrevious(i) {
    if (document.getElementById("stap" + i).style.display == "block") {
        x = i - 1;
        document.getElementById("stap" + x).style.display = "block";
        document.getElementById("stap" + i).style.display = "none";
    }
}

function subMenu(show) {
    if (show) {
        document.getElementById('sub_menu').style.display = 'block';
    } else {
        document.getElementById('sub_menu').style.display = 'none';
    }
}

function subMenu2(show2) {
    if (show2) {
        document.getElementById('sub_menu2').style.display = 'block';
    } else {
        document.getElementById('sub_menu2').style.display = 'none';
    }
}

//var state = 'none';

/*function showhide(layer_ref) {
    if (state == 'block') {
        state = 'none';
    }
    else {
        state = 'block';
    }
    if (document.all) { //IS IE 4 or 5 (or 6 beta)
        eval( "document.all." + layer_ref + ".style.display = state");
    }
    if (document.layers) { //IS NETSCAPE 4 or below
        document.layers[layer_ref].display = state;
    }
    if (document.getElementById && !document.all) {
        hza = document.getElementById(layer_ref);
        hza.style.display = state;
    }
}*/