var plus = new Image();     plus.src = "images/strom_plus.gif";
var minus = new Image();    minus.src = "images/strom_minus.gif";

function show(kat, imgname){
  var podmenu;
  if (podmenu = document.getElementById(kat)) {
	  var visible = (podmenu.style.display!='none');
	  if(visible){
    	  podmenu.style.display='none';
		  if (imgname) { eval("document."+imgname+".src=plus.src"); }
	  }else{
    	  podmenu.style.display='block';
		  if (imgname) { eval("document."+imgname+".src=minus.src"); }
	  }
  }
return false;
}

function hide(kat, imgname){
	var podmenu;
	if (podmenu = document.getElementById(kat)) {
		podmenu.style.display='none';
		if (imgname) { eval("document."+imgname+".src=plus.src"); }
	}
	return false;
}

function newImage(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}

function changeImage(kde, zdroj) {
	document.getElementById(kde).src = zdroj;
}

function openmenu(name){
	if (document.getElementById(name).style.visibility == "visible") document.getElementById(name).style.visibility="hidden" 
	else document.getElementById(name).style.visibility="visible";
}

function closemenu(name){
	document.getElementById(name).style.visibility="hidden"; 
}

function sirka_leveho_pruhu_js(){
	sirka = screen.width
	if (sirka<=1024) 
		sirka_leveho_pruhu_1 = 80
	else 
		sirka_leveho_pruhu_1 = 100;
	
	return sirka_leveho_pruhu_1;
}

function ChangeColor(div,color)
{
	var divObject = document.getElementById(div);
	divObject.style.color = color;
}