function HideContent(d) {
if(d.length < 1) { return; }
document.getElementById(d).style.display = "none";
}
function ShowContent(d) {
if(d.length < 1) { return; }
document.getElementById(d).style.display = "block";
}

function ShowArea(d) {
HideContent('Overview');
HideContent('Specifications');
HideContent('Order');
HideContent('Warranty');
ShowContent(d);
}

function HideContent(d) {
if(d.length < 1) { return; }
document.getElementById(d).style.display = "none";
}