Change Main Menu Colour

Hey Guys,
i’m trying to change the default font colour from grey (#404040) to black (#000000). I’m doing this by changing the following entry (stylesheet/typography) but nothing happens. What am i doing wrong?

body,
button,
input,
select,
textarea {
color: #000000;
font-family: sans-serif;
font-size: 16px;
font-size: 1.6rem;
line-height: 1.5;

Thanks alot for your advice!

Torben