function padout(number) { return (number < 10) ? '0' + number : number; }
   
   function prevFeature() {
      var index = 1;
      var item = document.getElementById("hp-feat-" + padout(index));
      var end = false;
      
      while(item && !end) {
         if(item.style.display == 'block'){
            end = true;
         } else {
            index++;
            item = document.getElementById("hp-feat-"+padout(index));               
         }
      }
      if(item) {
         var item2 = document.getElementById("hp-feat-" + padout(index - 1));
         if (!item2) {
            index = 1;
            while(document.getElementById("hp-feat-" + padout(++index))) {
               
            }
            item2 = document.getElementById("hp-feat-" + padout(index - 1));
         }
         item.style.display = 'none';
         item2.style.display = 'block';
      }
   }
   
   function nextFeature() {
      var index = 1;
      var item = document.getElementById("hp-feat-" + padout(index));
      var end = false;
      
      while(item && !end) {
         if(item.style.display == 'block'){
            end = true;
         } else {
            index++;
            item = document.getElementById("hp-feat-"+padout(index));               
         }
      }
      if(item) {
         var item2 = document.getElementById("hp-feat-" + padout(index + 1));
         if (!item2) {
            item2 = document.getElementById("hp-feat-01");
         }
         item.style.display = 'none';
         item2.style.display = 'block';
      }
   }