[Documentation Update]: Making UI of sign in page more attractive

[dhairyagothi]

Is there an existing issue for this?

• [X] I have searched the existing issues

Issue Description

fixing css of Sign in page

Suggested Change

css change of sign in page

Rationale

No response

Urgency

High

Record

• [X] I have read the Contributing Guidelines
• [X] I'm a GSSOC'24 contributor
• [X] I have starred the repository

[malvika-sinha]

I want to resolve the issue, kindly assign me the task