low image quality in /docs/guidelines/ in Dark Mode

[pushkarm029]

Description

Please describe your issue in few words here.

• Image quality significantly decreases user experience in dark mode.

How to reproduce

• simply go to this page : https://fossology.github.io/gsoc/docs/guidelines/

Screenshots

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Expected :

Versions

• Last commit id on master: 1ad1e12
• Operating System (lsb_release -a): windows 11
• Browser [e.g. chrome, safari]: microsoft edge

Logs

Any logs (if any) generated in