Fixed the home page image issue #140

[sarthakahuja07]

📝 Description

Fixed the alignment, and size of the cover image of the home page on a small screen.

🔧 Fixes #140

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📷 Provide related Screenshot/Gifs if any.

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• [x ] I have performed a self-review of my own code.
• [x] I'm a contributor in Hacktoberfest'21.

[sarthakahuja07]

@saloni-15 you can merge the PR :)