In Spirit – Can I make menu items different colors?

I’m working on a site where I want the menu items to be different colors. You once gave me code to do this with the accordion. I tried this :

.menu-item menu-item-type-custom menu-item-object-custom:nth-child(1) {

background-color: #000000;

}

But that’s not taking. Am I referencing this incorrectly? I suspect this is a syntax error on my part.