function zmen (na)
{
	var e1, e2;
	e1 = document.getElementById('fyz');
	e2 = document.getElementById('prav');

	if(na == "fyz")
	{
		e1.style.display = 'block';
		e2.style.display = 'none';
	}
	else
	{
		e1.style.display = 'none';
		e2.style.display = 'block';
	}
}

function openContactForm (kurz)
{
	window.open('contact_form.php?w=window&predmet=DotazNaKurz&kurz=' + kurz,'_blank', 'scrollbars=yes,menubar=no,resizable=yes,status=no,width=450,height=320');  
	return false;
}