function isNumberKey(evt)
{
var charCode = (evt.which) ? evt.which : event.keyCode
if (charCode > 31 && (charCode < 48 || charCode > 57))
  return false;
return true;
}

function isAllowedPass(evt)
{
var charCode = (evt.which) ? evt.which : event.keyCode
if (charCode > 31 && (charCode < 48 || charCode > 57) && (charCode < 65 || charCode > 90) && (charCode < 97 || charCode > 122))
  return false;
return true;

}

function darkBack(id) {
	document.getElementById (id).className = "katalog_item_dark";
}
function lightBack(id) {
	document.getElementById (id).className = "katalog_item";
}
function darkBackRight(id) {
	document.getElementById (id).className = "katalog_item_right_dark";
}
function lightBackRight(id) {
	document.getElementById (id).className = "katalog_item_right";
}