Checkout not working

Hi,

we are facing problems during the checkout phase, we are not able to complete the purchase.
We have tried with Paypal payment method, both in Test mode and in normal mode, as you can see from the screenshot there is no choice for payment method and pressing the button "Effettua ordine" (Complete order) does nothing.
This is the website shop url: http://21rue.liquidfactory.it/shop/