Add a dropdown as SOCIETIES

[YoshithaRathnayake]

Purpose

The purpose of this PR is to fix #352

Goals

Adding a dropdown as Societies and put Computer Fraternity inside it

Approach

I added a dropdown as Societies and put Computer Fraternity inside it

Screenshots

Desktop View

Mobile View

Preview Link

https://pr-386-sack-site-acf.surge.sh/

Checklist

• This PR doesn't commit any keys, passwords, tokens, usernames, or other secrets.
• I have read and understood the development best practices guidelines
• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation

Related PRs

Test environment

Learning

[YoshithaRathnayake]

@Piumal1999, @Hasthikagirihagama told "we want a hover dropdown and material kit has outdated so updating material kit is a hard work, put the dropdown in custom css". I created the hover dropdown look like material kit from custom css