HTML Tempate Rejected Don't know why Please Help Me...

Hi,
I just got rejection from my latest html template because of design quality.

Here is link to theme demo: https://tf.khadkaravi.com.np/dr-notebook/

Thank You.

Hi,

I have saw your item! You have to improve your item design quality. Lot’s of item are approved on marketplace with more good design.

Thanks!

Enhance your design according to UI design rules and enhance your design with trendy colors and forms to increase white space usage and emphasize your simple and simple design.
Design is very simple, you need to make many improvements.Finally, your design is reminiscent of a forum site.Try to make an original design showing a bookstore example

Regards Thank You