function open_chat(){
  var okno = window.open('http://www.babyonline.cz/chat/','babychat',
              'left=20,top=20,width=860,height=550,toolbar=0,resizable=1,status=0,menubar=0,location=0');
  okno.focus();
}

function open_vizitka(loc){
  var okno = window.open(loc,'vizitka',
              'left=20,top=20,width=900,height=620,toolbar=0,resizable=1,status=0,menubar=0,location=0');
  okno.focus();
}

function ukaz(id){
  var el2 = document.getElementById(id);
  el2.style.display='block';
}