New class does not work

Hi, I’m trying to insert a new class in Borderland thema, just to edit a body copy, like this:
.bodymusic
{
font: 400 normal 24px / normal “Gill Sans”, “Gill Sans MT”, “sans-serif”;
color: #FFFFFF;
text-align: left;
}
but it doesn’t work … I inserted this class on the bulletin board in the additional css, and I inserted the name of the class in the text, but nothing does not work. Maybe someone can help me? thanks