function oppna(url,x,y,scrolls) {
  {
  w=(screen.availWidth/2)-(x/2)
  h=(screen.availHeight/2)-(y/2)

  popwin = window.open(url, '', 'width='+x+',height='+y+',status=no,menubar=no,scrollbars='+scrolls+',resizable=no,titlebar=no,dependent=yes,left=' + w + ',top=' + h + '');
  }
}