function showcase(elm) {
     var currentDiv   = document.getElementById(elm);
     var contents     = document.getElementById('show-content').getElementsByTagName('DIV');
     var nav          = document.getElementById('show-nav').getElementsByTagName('A');
     var start = function(){
         // loop through all elements and assign functions
         var i = contents.length;
         while(i--){
             if(nav[i] == currentDiv) {
                 contents[i].style.display = 'block';
     	           currentDiv.style.backgroundPosition = "0 0px";
     	           continue;
             }
             contents[i].style.display = 'none';
             nav[i].style.backgroundPosition = "0 -86px";
             nav[i].onclick = function(){
                 switchTabs(this);
                 return false;
             };
         }
     };
     
     var switchTabs = function (newElm){
         currentDiv = newElm;
         start();
     };
     
     return start;
 };
 window.onload = function(){
     var myshow = showcase('n-anti');
 	   myshow();
 };