Items submission rejected

I got this message when I uploaded my script
Thank you for your submission. We have completed our review of “Metro School Manager” and unfortunately we found it isn’t at the quality standard required to move forward, and you won’t be able to re-submit this item again.

We appreciate the effort and time you’ve put into creating your item. And we’d be happy to help make sure your next entry will meet our submission requirements. Here’s our advice:

Visit our forums and ask fellow authors for feedback. Our helpful community will be glad to lend a hand.

Check out this Help Center article to understand why and how items get rejected.

Remember you can get help, in the form of tutorials or skilled professionals, on Envato Tuts+ and Envato Studio.

We hope to see a new submission from you soon!

All the best!

Envato Quality team

Can you help me how do I fix this issue
My Demo web is

I think the problem is with your design. You need to change the whole design to look like a premium product. Some texts are hard to read.

Thanks for your advice. The design in the front or backend that look like un premium?

I have seen the frontend. Some texts are not easily readable

Big thanks for you. How about my backend?

Backend might be ok. I haven’t seen it.

If you are eager to check it, because I have idea about my rejection.

No idea