Css variables declaration

//penguin class should declare the --penguin-skin variable and assign it to gray//
what should i do to complete the challenge and do as said above.I am pretty much stuck here.Any help would be appreciated.

change the penguin skin from black to gray it should look iike this

--penguin-skin: gray;
--penguin-belly: white;
--penguin-beak: orange;


Maybe u should show us u code.