// Promo Code Calculation

function  doPromo(thisform) {

var itemAmount = thisform.itemprice.value;
var discount = itemAmount;
var promoCode = thisform.promo.value;


if (promoCode == "SCOTTSDALE") {
alert ("Free Shipping is only valid within the United States.");
thisform.shipping.value = 0 }

else if (promoCode == "autogeek") {
var discount = 249.00 }

else if (promoCode == "BMW") {
var discount = 199.00 }

else if (promoCode == "USC") {
var discount = itemAmount = 199.00 }

else { var discount = itemAmount * 1 }

var discount=Math.round(discount*100)/100
thisform.amount.value=discount;

}