Reduce unused CSS

### Description

Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity

https://www.youtube.com/watch?v=txAE6yT0Eu8

here is the link to of the resource : - https://developer.chrome.com/docs/lighthouse/performance/unused-css-rules/?utm_source=lighthouse&utm_medium=lr

### Epic/Story

_No response_

### Have you provided an initial effort estimate for this issue?

I have provided an initial effort estimate

Start by reviewing the website's stylesheets and running the Lighthouse unused-CSS audit, using the linked Chrome guidance as context. Done means unused rules are reduced and CSS not needed for above-the-fold content is deferred, with lower network bytes verified by the audit.

Written by the indexing model from the issue text.