// JavaScript Document
function changeSty(tab){

  
if (tab == 1) {
	document.getElementById('tab1').className="tab1 on1";
	document.getElementById('tabcontent1').style.display = 'block';
	
	if  (document.getElementById('tab2')) {
	    document.getElementById('tab2').className="tab4";
		document.getElementById('tabcontent2').style.display = 'none';
	}
		
}

else if (tab == 2) {
	document.getElementById('tab1').className="tab1";
	document.getElementById('tabcontent1').style.display = 'none';
	
	if  (document.getElementById('tab2')) {
	    document.getElementById('tab2').className="tab4 on3";
		document.getElementById('tabcontent2').style.display = 'block';
	}
	
	
}

}