function toggleCurrent(tab)
{

    var i = 1;
    
    var nextTab = document.getElementById("OverlayTab"+ i);
    var nextPanel = document.getElementById("OverlayPanel"+ i);
    
    while (nextTab != null || nextPanel != null)
    {
        if(nextTab!= null)
        {
            nextTab.className = "";
        }
        if(nextPanel!= null)
        {
            nextPanel.style.display = "none";
        }
        i = i + 1;
        
        nextTab = document.getElementById("OverlayTab"+ i);
        nextPanel = document.getElementById("OverlayPanel"+ i);
    }


    nextTab = document.getElementById("OverlayTab"+ tab);
    nextPanel = document.getElementById("OverlayPanel"+ tab);

    nextTab.className = "current";
    nextPanel.style.display = "inline";
    
}