// JavaScript Document
 function tabSwitch(new_tab, new_content) {  
       
     document.getElementById('content_1').style.display = 'none';  
     document.getElementById('content_2').style.display = 'none';  
     document.getElementById('content_3').style.display = 'none';         
     document.getElementById(new_content).style.display = 'block';     
       
   
     document.getElementById('tab_1').className = '';  
     document.getElementById('tab_2').className = '';  
     document.getElementById('tab_3').className = '';         
     document.getElementById(new_tab).className = 'on';        
   
}