function avancar(totalSubGaleria, subGaleriaAtual)
{
    if(subGaleriaAtual.value == totalSubGaleria)
        return;
    else
    {
        idSpan = subGaleriaAtual.value * 3;
        
        document.getElementById('subGaleria' + subGaleriaAtual.value).style.display = 'none';
        subGaleriaAtual.value = (subGaleriaAtual.value + 1);
        document.getElementById('subGaleria' + subGaleriaAtual.value).style.display = 'inline';
    }    
}
function voltar(totalSubGaleria, subGaleriaAtual)
{
    if(subGaleriaAtual.value == 1)
        return;
    else
    {
        document.getElementById('subGaleria' + subGaleriaAtual.value).style.display = 'none';
        subGaleriaAtual.value = (subGaleriaAtual.value - 1);
        document.getElementById('subGaleria' + subGaleriaAtual.value).style.display = 'inline';
    }    
}