How to make a navbar menu fro Frontend Mentor

Hi everyone, I am having a trouble making the transparent menu from Frontend Mentor Challenge. It is not that I don't know how to make it transparent but I cannot match the color in the image. This is their given color: Soft Blue: hsl(231, 69%, 60%) , Soft Red: hsl(0, 94%, 66%), Grayish Blue: hsl(229, 8%, 60%), Very Dark Blue: hsl(229, 31%, 21%). Also, while I am at it, I want to ask about what is the best way to make a navbar with HTML, CSS AND JS. I also want into trouble making nav whenever I code so I want to know the best way to do it.