PLEASE HELP WITH TEXT COLOUR IN NAV BAR

[wendyj02]

HI
I am at my witts end, I would like to change the text colour in my Nav bar from WHITE to BLACK and when I do and preview they are all still WHITE. Surley there is a simple way. I have made two more nav bars and same problem. If I use colour editior the default text "LIGHT TEXT" is white but if I change this my header changes too.
See in attachment I have changed text to black but on preview still white.
THANKYOU