Good to see something new posted here.
The biggest weakness of both these designs is font choice. Both sites display inconsistencies with fonts, and just poor font choice in general. Your fonts are noisy, and borderline unreadable. Check out this answer from
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for more pointers.
Second, I think your color choice is a little uninspired. The dark website looks much nicer in terms of color choice, but the Nova site looks "drab" with the choice of green. Relying on borders to separate content components doesn't look great. I spent a couple minutes shifting some colors around:
I've always found sites like
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and
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helpful when picking color palettes. I think if you revised the shades of green you use, this site would look much better!
Lastly, I think if there was a little more thought put into design decisions, both of your designs would look more refined. Think why each element is there, and the purpose it serves (eg. why is there a random cat image to the right? what purpose should it serve?).
Overall, this is a good start to designing sites. I'm sure you won't agree with some of the things I said, but check out the links and hopefully, you'll find them useful! Keep up the design work!