void RotateThing(Vector3 euler)
{
   ThingTransform.Rotate(euler);
   var newBounds = GetRotatedBounds(Quaternion.Euler(euler), Bounds);
   Debug.Log($”size: width {newBounds.x}, height {newBounds.y}”);
}


Vector3 GetRotatedBounds(Quaternion rot, Vector3 bounds)
{
   return rot * bounds;
}