Fix mobile screen code block overflow issue

[prvn347]

@hkirat The previous pull request (#289 ) was closed because that has some yarn.lock conflict.

• This pr fixes the codeblock overflowing issue.
• In this I have implemented CSS adjustments to ensure code blocks are properly contained within the viewport on mobile devices.

Resolves #288

• [x] I have performed a self-review of my code
• [x] I assure there is no similar/duplicate pull request regarding same issue