Slick! My feedback:

• Consider respecting the user agents color scheme preference (I like to have light mode on day and dark mode on night — don’t overwrite that without my permission if you already have both themes).
• Contrast is too low in the dark theme and way too low (basicly unusable) in the light theme.
• Consider increasing font size, esp. for code blocks
• For me it’s wierd that posts are kinda centered but not really. Since most (not all) languages are left to right, I’m used to start looking on the left side, not the right. Consider centering the post properly.
• Consider making the hover animations faster.
• In dark mode, the icon button hover text is black on dark gray and therefore basicly unreadable.

What is this dot between the three-dot menu button and the time stamp?

Image

Personally, I don’t really like that the post is displayed transparently over the post list. This makes it a lot harder for me to focus on the content. Maybe I’m not the target group for a design like this.