function showBlock(blockId)
  {
    if(document.getElementById(blockId).style.display=="block") {
	document.getElementById(blockId).style.display = "none";
    } else {
	document.getElementById(blockId).style.display = "block";
    }
  }
  function hideBlock(blockId)
  {
    if(document.getElementById(blockId).style.display=="none") {
	document.getElementById(blockId).style.display = "block";
    } else {
	document.getElementById(blockId).style.display = "none";
    }
  }
  function nastavCookies() {
    var vyprs=new Date();
    vyprs.setDate(vyprs.getDate() - 1);
    document.cookie="rozsirene=false; expires="+vyprs.toGMTString()+";";
    vyprs.setDate(1 + 1 + vyprs.getDate());
    document.cookie="rozsirene=false; expires="+vyprs.toGMTString()+";";
  }
  function smazCookies() {
    var vyprs=new Date();
    vyprs.setDate(vyprs.getDate() - 1);
    document.cookie="rozsirene=false; expires="+vyprs.toGMTString()+";";
  }