Method to combine 2 colors in css

Hi,
I got a design to use 2 colors as background/border color.
What is the best method to use?
one color already has some kind of transparency in it.

Hi buddy, if here you want to do use 2 colours one as background-colour and the second one is the border-colour then for that there are 2 specific styles existed.

The first one is background-color: red; and the second one is the border-color: blue;

This how you can do use the 2 specific styles element.

Hope this helped.