function showByID(id, check)
{
    if(check && document.getElementById(id).style.visibility == 'collapse')
    {
        document.getElementById(id).style.visibility = "visible";
    }
    else if(!check)
    {
        document.getElementById(id).style.visibility = "visible";
    }
}

function hideByID(id)
{
    document.getElementById(id).style.visibility = "collapse";
}

function hideAll()
{
    hideByID("a1");
    hideByID("a5");
}

function changeColor(id, id2, normal)
{
    if(normal)
    {
    	document.getElementById(id).style.background = "";
        document.getElementById(id2).style.color = "#FFFFFF";
    }
    else
    {
        document.getElementById(id).style.background = "#FFFFFF";
        document.getElementById(id2).style.color = "#017b93";
    }
}