Thank you for this. Wow! That’s pretty masterful. Everything is so visible that I actually turned my brightness down! The active post editor at the bottom really makes itself evident. It’s not as prominent in the normal dark theme.
The editor has a bit of a “street neon” underglow, though. You might consider toning it down a notch or two (either darken the hue or add more red/green). Thinning the colored border by one pixel would possibly be ideal but I assume that border thickness isn’t one of the theme parameters.
I really like the high-contrast dark.