function togglevisibility()
{
var content = document.getElementById('content');
var footer = document.getElementById('footer');
if (content.style.display == 'none' & footer.style.display == 'none')
{
content.style.display = 'block';
footer.style.display = 'block';
}
else
{
content.style.display = 'none';
footer.style.display = 'none';
}
}