Style the admin page and make all the functionality working

[marija04]

What was the feature/problem?

Add some styles on admin page and make it fully functional.

How does this PR address the above feature/problem?

Whit this PR the admin page looks as requested and everything is functional.

Check lists (check x in [ ] of list items)

• [ ] Test passed
• [ ] Coding style (indentation, etc)

Additional Comments (if any)

{Please write here}