Alternate header text colors

[Stanislas_Desma]

Hello,
I would like to change the color of one of the titles of my main menu. However I can't change only this title but all the titles of my header. I use the Showcase theme. I can't find in the code the way to change the color of a single title.
I would like this title to be highlighted in relation to the other titles of my menu
Would someone be able to help me?

Thank you very much