Code blocks in Standard Modules Reference are not readable in dark mode

[samestep]

Similar to shader-slang/slang#7442; although #119 seems to have fixed code highlighting in the User Guide, the Standard Modules Reference still seems broken. For instance, on the page for IArithmetic.add, the ., (, ), and ; characters are nearly invisible:

light mode	dark mode

I suspect that this is due to the Standard Modules Reference still using the same light color theme despite now not setting the background to a light color.