creted Dark mode feature in website

[riyanrathore26]

fixes #63

🛠️ Fixes Issue : ""

👨‍💻 Changes proposed:

I created Dark mode feature for websited i added dark mode feature button in navbar it will handle user request with onclick function

✔️ Check List (Check all the applicable boxes)

• [ ] My code follows the code style of this project.
• [ ] This PR does not contain plagiarized content.
• [ ] The title of my pull request is a short description of the requested changes.
• [ ] I am a participant of Hacktoberfest 2022.

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