opacity in navbar after scrooling change the color background

Hi,

Please provide your website URL.
Need to take a look in order to try and provide a solution.

Thank you

Hello,

Add the following custom CSS to customize-> Additional CSS

#main-nav {
    background: transparent;
}
#main-nav.fixed {
    background: red!important;
}

Hope it helps and let me know if you require any further assistance.

Hi, I have tried this right now, but then I scroll down and the background colour appears and stay in the window when I got back to the top and the transparency not appears anymore.
this is my site:
https://www.pensesocialpro.com.br

I would to like to design the top header like this:
https://in-marketing.co.uk/

Thank you so much for your replies

Any fix for this?