function popup(){
  window.open('/teilnahmebedingungen', 'windowname2', 'width=500, height=260, top=200, left=100, directories=no, location=no, menubar=no, resizable=1, scrollbars=1, status=no, toolbar=no'); 
}

function anleitung(){
  window.open('/anleitung', 'windowname3', 'width=500, height=220, top=200, left=100, directories=no, location=no, menubar=no, resizable=1, scrollbars=1, status=no, toolbar=no'); 
}