anchor.diff:        ),
         backgroundColor: Colors.white,
         body: ListView(
  -        padding: EdgeInsets.symmetric(horizontal: 20),
  +        padding: const EdgeInsets.symmetric(horizontal: 20),
           children: [
             Container(
               margin: const EdgeInsets.symmetric(vertical: 20),
  -            child: Image(
  +            child: const Image(
                 image: AssetImage('assets/images/ts_10_11019a.jpg'),
                 height: 350,
               ),
             ),
  -          Text(
  +          const Text(
               'Amanda\'s Polo Shirt',
               style: TextStyle(
                 fontSize: 20,
  
positive.code:             paymentItems: _paymentItems,
              style: GooglePayButtonStyle.black,
              type: GooglePayButtonType.pay,
              margin: EdgeInsets.only(top: 15.0),
              onPaymentResult: onGooglePayResult,
              loadingIndicator: Center(
                child: CircularProgressIndicator(),
              ),
            ),
  
negative.code:             ),
            ),
            const SizedBox(height: 15),
            const Text(
              'Description',
              style: TextStyle(
                fontSize: 15,
  