anchor.diff:                        _isSelected = !_isSelected;
                       });
                     },
  -                  splashColor: Theme.of(context).colorScheme.primary.withAlpha(30),
  +                  // Generally, material cards use onSurface with 12% opacity for the pressed state.
  +                  splashColor: colorScheme.onSurface.withOpacity(0.12),
  +                  // Generally, material cards do not have a highlight overlay.
  +                  highlightColor: Colors.transparent,
                     child: Stack(
                       children: <Widget>[
                         Container(
                           color: _isSelected
  -                          ? Theme.of(context).colorScheme.primary.withAlpha(41)
  +                          // Generally, material cards use primary with 8% opacity for the selected state.
  +                          // See: https://material.io/design/interaction/states.html#anatomy
  +                          ? colorScheme.primary.withOpacity(0.08)
                             : Colors.transparent,
                         ),
                         TravelDestinationContent(destination: widget.destination),
                         Align(
                           alignment: Alignment.topRight,
                           child: Padding(
  -                          padding: const EdgeInsets.all(4.0),
  +                          padding: const EdgeInsets.all(8.0),
                             child: Icon(
                               Icons.check_circle,
  -                            color: _isSelected ? Colors.white : Colors.transparent,
  +                            color: _isSelected ? colorScheme.primary : Colors.transparent,
                             ),
                           )
                         ),
                       ],
  -                  )
  +                  ),
                   ),
                 ),
               ),
  
positive.code:                   onTap: () {
                      print('Card was tapped');
                    },
                    splashColor: Theme.of(context).colorScheme.primary.withAlpha(30),
                    child: TravelDestinationContent(destination: destination),
                  ),
                ),
  
negative.code: 
    @override
    Widget build(BuildContext context) {
      final ColorScheme colorScheme = Theme.of(context).colorScheme;
  
      return SafeArea(
        top: false,
        bottom: false,
  