function highlight(td)
{
    var tdEven = document.getElementById(td);
    var idTdEvenCategory = td + "categoryEven";
    var tdEvenCategory = document.getElementById(idTdEvenCategory);


    tdEven.className = "even";
    tdEvenCategory.className = "categoryEven";
}

function removehighlight(td)
{
    var tdEven = document.getElementById(td);
    var idTdEvenCategory = td + "categoryEven";
    var tdEvenCategory = document.getElementById(idTdEvenCategory);


    tdEven.className = "odd";
    tdEvenCategory.className = "categoryOdd";
}