Add inverted link color

[ghost]

in inverted color schemes, the link text becomes very low-contrast (especially with the light font-weights in SQ2). We can improve readability by tinting the $C_link to, e.g. 5EB4FF.

current:

proposed:

[ghost]

I was thinking just doing this in .inverted context, but @rxb has proposed finding a better middle-ground link color that works in both places. Either way works for me