Gradient type, one of 'linear', 'radial', or 'conic'.
Rotation angle in degrees. Used by linear and conic.
Horizontal centre, 0–100 %. Used by radial and conic.
Vertical centre, 0–100 %. Used by radial and conic.
Gradient stops, in order of increasing position. Must have at least 2 stops.
Represents a gradient fill, with type, angle, centre, and stops. This is how gradients are stored in the diagram model, and is not the industry standard.