...
In addition, it takes the following attributes:
start center - a list of 2 elements with the first value used to set the startX centerX attribute of the LinearGradient and the second value to set the startY centerY attribute.
end - a list of 2 elements with the first value used to set the endX attribute of the LinearGradient and the second value to set the endY attribute.
stops - The value of the stops attribute should be a List of 2-element Lists containing an offset and color: [[0.0, black], [1.0, red]]
...