Push Pull

function viewPDF (event) {
          var link = encodeURI(event.target.href);
          var ifrm= document.createElement('iframe');
          var width = 800;
          var left = 100;
          
          ifrm.src = link;
/// для примера
          ifrm.src  = 'http://mozilla.github.io/pdf.js/web/viewer.html?file=http%3A%2F%2Fasync5.org%2Fmoz%2Fpdfjs.pdf';
          ifrm.setAttribute('style', 'z-index: 9999;width: '+width+'px; height: 500px; position: fixed; top: 100px; left: '+left+'px;');
          var close = document.createElement('button');
          close.setAttribute('type', 'button');
          close.innerHTML = 'Закрыть';
          close.onclick = function() {
                 document.body.removeChild(ifrm);
                 document.body.removeChild(close);
          }
          close.setAttribute('style', 'z-index: 9999;position: fixed; top: 100px; left: '+  (left+width+20) +'px;');
          document.body.appendChild(ifrm);
          document.body.appendChild(close);
}

function multiply(){
      document.getElementsByClassName('window')[0].innerhtml = '';    
      var a=document.forma1.t1.value*2;
    
      alert("Ширина окна слишком велика"); 
      var s=(a-5)/19;
      var b=a+30;
      if((a+30)>580)
        {
        alert("Ширина окна слишком велика"); 
        return(0);
        }
      
      s = Math.ceil(s); 
      document.getElementsByClassName('window')[0].style.width = s*19; 
      var i=0;
      for(i=0;i<s;i++)
        {
        var newdiv = document.createElement('div');
        newdiv.className = 'lamel' ;
        document.getElementsByClassName('window')[0].appendChild(newdiv);
        }
      document.forma1.res.value=s; 
    }    

document.addEventListener('readystatechange', function(){
    var btn = document.getElementsByName('button');
    btn.addEventListener('click', multiply);
    });