//"hover" pomoci obrazku
 
 p1 = new Image;
 p1.src = "img/bt_01.jpg";
 p1b = new Image;
 p1b.src = "img/bt2_01.jpg";
 
 p2 = new Image;
 p2.src = "img/bt_02.jpg";
 p2b = new Image;
 p2b.src = "img/bt2_02.jpg";
 
 p3 = new Image;
 p3.src = "img/bt_03.jpg";
 p3b = new Image;
 p3b.src = "img/bt2_03.jpg";
 
 p4 = new Image;
 p4.src = "img/bt_04.jpg";
 p4b = new Image;
 p4b.src = "img/bt2_04.jpg";
 
 p5 = new Image;
 p5.src = "img/bt_05.jpg";
 p5b = new Image;
 p5b.src = "img/bt2_05.jpg";
 
 p6 = new Image;
 p6.src = "img/bt_06.jpg";
 p6b = new Image;
 p6b.src = "img/bt2_06.jpg";
 
 p7 = new Image;
 p7.src = "img/bt_07.jpg";
 p7b = new Image;
 p7b.src = "img/bt2_07.jpg";
 
 p8 = new Image;
 p8.src = "img/bt_08.jpg";
 p8b = new Image;
 p8b.src = "img/bt2_08.jpg";
 
 p9 = new Image;
 p9.src = "img/bt_09.jpg";
 p9b = new Image;
 p9b.src = "img/bt2_09.jpg";

 p10 = new Image;
 p10.src = "img/bt_10.jpg";
 p10b = new Image;
 p10b.src = "img/bt2_10.jpg";

 
 
 
 function navMouseOver(imgid,imgnew) {
    document.images[imgid].src=eval(imgnew + ".src");
         
 }


//pro overeni formulare

function checkForm ()
{
  re = new RegExp("^[^.]+(\.[^.]+)*@([^.]+[.])+[a-z]{2,4}$");
	requiredFields = getElByClassName("required","requiredc");
  var warning = "";
  var first = "";
	for (var i=0;i<requiredFields.length;i++)
	{
		if ( requiredFields[i].value == "" ){
				warning = warning + requiredFields[i].title + "\n";
				if (first == "") first = requiredFields[i];
				requiredFields[i].className = 'requiredc';
		}
    else { 
      requiredFields[i].className = 'required';
      if (requiredFields[i].id == 'email') {
          if (!re.test(requiredFields[i].value)){
                  requiredFields[i].className = 'requiredz';
                  warning = warning + requiredFields[i].title + "\n";
                  if (first == "") first = requiredFields[i];
          }
      }
    }
	}
	if (warning == "") return true;
  else {
      alert(warning);		
      first.focus();
			return false;
  }
}

function getElByClassName(className1,className2) 
{ 
	var arr = new Array(); 
	var elements = document.getElementsByTagName("*");
	for ( var i = 0; ( element = elements[i] ); i++ )
	{
		if ( (element.className.indexOf(className1) != -1) || (element.className.indexOf(className2) != -1) )
		{
			arr[arr.length] = element;
		}
	}
	return arr;
}

function checkbox (box,ktery){
  if (box.checked == true) document.getElementById(ktery).checked = false;
}