Fixed navbar issues, added warnings in pre-reg component and made it responsive

[rishitkamboj]

Earlier it was not responsive on mobile devices it was scattered

Before:

After:

Form was being able to submit with empty data only and that is something that should not be there

Now it shows a warning if no information is there

Fixed margins and paddings on the home page. Also there was no space between the components(courses) and stuff. Added gap there

Kindly take a look. Thank you

[Rudra-Sankha-Sinhamahapatra]

good job