function increasequantity( id ) {
	obj = document.getElementById(id);
	if ( obj.value < 999 ) { obj.value++; }
}

function decreasequantity( id ) {
	obj = document.getElementById(id);
	if ( obj.value > 1 ) { obj.value--; }
}

function selectquantity( id ) {
	obj = document.getElementById(id);
	if ( ( obj.value > 0 ) && ( obj.value < 999 ) && document.getElementById('quantity') ) { 
		document.getElementById('quantity').value = obj.value;
	}
}

function toggleHidden( id ) {
	if ( document.getElementById(id).className == "hidden" ) { document.getElementById(id).className="visible"; }
	else { document.getElementById(id).className="hidden"; }
}