Glad to see a dark here on Pinside!
It does need some tweaks. The dark gray really needs to go darker. As it stands, the color of the white text doesn't really pop out on a dark greyish background.
For example, check out Twitter's dark mode. Text really pops off the screen, and much easier to read.
Also, the blue-ish highlight for OP's posts looks wrong and hard to read.
All things that can be easily tweaked. A step in the right direction for sure!