Hi@MD,
By default, you can't see any border to your Container. But you can use BoxShadow inside decoration. This helps you to add the border in the container level. You can see the below example.
decoration: BoxDecoration(
borderRadius: BorderRadius.circular(20),
color: Colors.lightGreen,
boxShadow: [
BoxShadow(color: Colors.red, spreadRadius: 3),
],
),
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