Gets the fill colour set by the last g, rg or k operator, in DeviceGray, DeviceRGB or DeviceCMYK; or
null when there is none (the initial black then applies).
public PdfColor? Color { get; }
ISO 32000-2 §12.7.4.3 and §8.6.8, Table 73. The components are as written, not clipped. A colour set in a named colour space
(cs, sc, scn) is not read here and stays in OtherOperators, after which it applies.