awesome-uiwidgets/AwesomeUIWidgets/Assets/Scripts/RaycastableScene/custom_card.cs

using uiwidgets;
using Unity.UIWidgets.foundation;
using Unity.UIWidgets.painting;
using Unity.UIWidgets.ui;
using Unity.UIWidgets.widgets;

namespace UIWidgetsSample.RaycastableScene {
    public class CustomCard : StatelessWidget {
        public CustomCard(
            Key key = null,
            Widget child = null) : base(key: key) {
            this.child = child;
        }

        public readonly Widget child;
        
        const float _defaultElevation = 1.0f;
        const Clip _defaultClipBehavior = Clip.none;

        public override Widget build(BuildContext context) {
            return new Container(
                    margin: EdgeInsets.only(left: 5f, right: 5f, top: 4f, bottom: 4f),
                    color: Colors.white,
                    decoration: new BoxDecoration(borderRadius: BorderRadius.all(Radius.circular(20.0f))),
                    child: child
                );
        }
    }
}