What is the change?

I improved the alignment of the dark mode button and removed unnecessary code from the codebase

Now What is mean by unnecessary code?
The dark mode.js is defined two times in the codebase both in app.js and footer.ejs which causes an alignment issue but I fixed that

before

after

Related issue?

issue: #114 Align dark mode button to bottom left corner

How was it tested?

I tested the code by running it on my localhost and also test its responsiveness and other parameters using the chrome inspect element.

Checklist:

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• Have you followed the Contribution Guidelines while contributing.
• Have you checked there aren't other open Pull Requests for the same update/change?
• Your submission doesn't break any existing feature.
• Have you tested the code before submission?