You can skip to the bottom if you only care about the question.
My original goal was to control FrameLabel color from a notebook level opposed to doing it explicitly in Graphics:
Graphics[{}, Frame -> True, FrameLabel -> {"Xlabel", "Ylabel"}, LabelStyle -> Orange]
Initial problem: first of all it does not work
CurrentValue[ EvaluationNotebook[], {GraphicsBoxOptions, LabelStyle}] = Orange;
Graphics[{}, Frame -> True, FrameLabel -> {"Xlabel", "Ylabel"}]
I won't go through all the details but among others I learned that LabelStyle is applied after DefaultLabelStyle, which was not working either. Then I was playing with FrameStyle, DefaultFrameStyle, StyleData["Graphics"], StyleData["GraphicsFrame"], to no avail.
CurrentValue[ nb, {GraphicsBoxOptions, DefaultLabelStyle}] is shielded by something and DefaultFrameStyle affects the frame color as well so it is not the same.
In addition to that I am aware of existance of FrameTicksStyle and friends.
The final question is, given all possible GraphicsBox' elements like ticks, ticks' labels, frame itself, frame label etc etc. Where and in what order do they inherit their style from, step by step or in form of a graph.
Is there any hope to try to set those styles on a notebook level (not on a stylesheet level nor expression level)?
