Website: Add blur effect to navbar

[theabhayprajapati]

Improved the Navbar by adding a backdrop which make the background bit of glassy.

[theabhayprajapati]

Improvement

Notice the Navbar on the top

With Backdrop

Without Backdrop

[luzpaz]

@yorikvanhavre ping

[theabhayprajapati]

hii @luzpaz do we have a discord channel

[luzpaz]

https://forum.freecadweb.org/viewtopic.php?f=9&t=60988

[luzpaz]

Please rename this issue so we can quickly identify what it's addressing

[theabhayprajapati]

Hey Actually I had created this issue for PR which can. improved the Navigation bar by adding blur effect on the background.

[luzpaz]

@yorikvanhavre what do you think?

[yorikvanhavre]

Sorry about the delay guys! Great fix!