What are the Codeigniter Submission Guidelines in CodeCanyon?

I am suppose to sell some applications developed using Codeigniter but I could not find any guidelines related to that. I need to understand what type of coding standard they look in Codeigniter systems.
(What type of template libraries I can use, what are the variable declaration standards, how I can integrate JavaScript or JQuery etc.)

There’s no limitations on which libraries you can use, and probably no code-standardization either. You should use the code-standardization used by the framework you’re working with, that being said, following PSR-2 coding style guidelines would probably be a good idea.

Always make sure your code is clean and readable. Be considerate with what libraries you’re using and ensure compatibility with the minimum version you’re going to be supporting. Also when submitting your item, make sure you specify the minimum requirements of your product.

I am created Project in Code Igniter but rejected please check my project and guide what whas the issue

username: admin
password: 123

When your submission gets decline, you get a reason of why that has happened. Read the reason and try to improve on it.

As a suggestion, try using Bootstrap for any related front-end things, as your current layout looks outdated to say the least.