Shipping address section

overflow.checkout({
  paymentMethods: ['card'],
  shippingAddress: {},
});

overflow.checkout({
  paymentMethods: ['card'],
  shippingAddress: {
    header: { text: 'Shipping address' },
    fields: {
      fullName: {},
      country: { supportedCountries: ['US', 'CA', 'GB'] },
      line2: { hidden: true },
    },
  },
});

overflow.checkout({
  paymentMethods: ['card'],
  shippingAddress: {
    autocomplete: { enabled: true },
  },
});

checkout.on('onSubmit', ({ value }) => {
  // value.shippingAddress: { line1, line2?, city, state, postalCode, country, ... }
});