Update Hero.css and readme.md

[sb-decoder]

Which feature you are going to add

update readme.md and hero.css

Describe the solution you'd like

added color and font family to description in landing page and curved the button of discover and play

Screenshots

[Arun9739]

@sb-decoder Go ahead
Star the repo 🌟 to show your support.

[sb-decoder]

I have already made a PR. Please check.