If non-null, the box will expand to fill its parent and position its child within itself according to the given value. If the incoming constraints are unbounded, then the child will be shrink-wrapped instead.
Ignored if child is null.
example: Image will have different alignment in xs and lg LBreakPoint
... child: LBox( alignment: LBoxAlignment( xs: Alignment.centerLeft, lg: Alignment.bottomRight, ), height: LBoxDimension( xs: 250.0, sm: 280.0, md: 350.0, lg: 450.0, xl: 500.0 ), width: LBoxDimension( xs: 250.0, sm: 280.0, md: 350.0, lg: 450.0, xl: 500.0 ), child: Image.network("https://source.unsplash.com/random/", height: 100.0, width: 100.0), ), ...
final LBoxAlignment alignment;