function toggle_layer(dlayer)
    {
        
        if (document.getElementById(dlayer).style.display == 'none')
        {
            
            document.getElementById(dlayer).style.display='';
            
        }
        else
        {
            
            document.getElementById(dlayer).style.display="none";
            
        }
        
    }
    
    function close_layer(dlayer)
    {
    	
        if (dlayer)
        {
            
            document.getElementById(dlayer).style.display="none";
            
        }
    	
    }
    
    function open_layer(dlayer)
    {
    	
        if (dlayer)
        {
            
            document.getElementById(dlayer).style.display="";
            
        }
    	
    }