[ruslan_mart]

window.onscroll = function() {
   var s = document.documentElement.scrollTop,
       e = document.getElementById('test').style;
  
   if(!this.scrollFlag && s > 100) {
      this.scrollFlag = true;
      e.display = 'none';
   }
   else if(this.scrollFlag && s < 100) {
      this.scrollFlag = false;
      e.display = 'block';
   }
}