function cambio(e)
{
    var element = document.getElementById('line').value
    n = element.length;
    t = 164;
    
    if (n > t)
    {
        document.getElementById('line').value = document.getElementById('line').value.substring(0, t);
        document.getElementById('cont').innerHTML = 'Te quedan <strong>' + num + '</strong> caracteres';
    }
    else
    {
        num = t - n;
        document.getElementById('cont').innerHTML = 'Te quedan <strong>' + num + '</strong> caracteres';
    }
    if(e)
    { 
        e = e;
        characterCode = e.which ;
    }
    else
    {
        e = event;
        characterCode = e.keyCode;
    }
} 

function refresh()
{
    if (document.getElementById('line').value == "Haz clic para escribir")
        document.getElementById('line').value = "";
}

function checkEmpty()
{
    var element = document.getElementById('line').value;
    
    if(element == '')
    {
        document.getElementById('line').value = 'Haz clic para escribir';
    }
}