function highlight(id)
{
		element = document.getElementById(id);
		element.style.color = "#ff6600";
		setTimeout("normal(element)", 2500);

}
function normal(id)
{
//		element = document.getElementById(id);
		id.style.color = "black";
}
function prakticky_priklad(id) {
		        window.open("prakticky-priklad.php", '','width=257,height=444,menubar=no,toolbar=no,directories=no,top=50,left=0');
}