Validator...pare błędów! Opcje

[Joachim Peters]

Witam,

Ostatnio staram się robić strony zgodne z validator'ami, ale natrafiłem na taki problem.
Kod html jest w 100% poprawny, ale inaczej z css.
Gdy sprawdza swoją strone pokazuje że strona jest zgodna z css ale niżej jest napisane coś takiego:

[HTML] pobierz, plaintext 
Warnings
 
Line : 16 font-family: You are encouraged to offer a generic family as a last alternative
Line : 16 (Level : 2) font-family: You are encouraged to offer a generic family as a last alternative : *
Line : 20 (Level : 1) You have no color with your background-color : .logo
Line : 26 (Level : 1) You have no color with your background-color : .page_name
Line : 33 (Level : 1) You have no color with your background-color : .menu_top
Line : 39 (Level : 1) You have no color with your background-color : .news
Line : 45 (Level : 1) You have no color with your background-color : .menu
Line : 51 (Level : 1) You have no color with your background-color : .center_left
Line : 57 (Level : 1) You have no color with your background-color : .center_right
[HTML] pobierz, plaintext 

to są te błędy czy nie?Jeżeli tak to jak je naprawić?

kod css wygląda tak:

[HTML] pobierz, plaintext 
* {
font-family: tahoma;
}
 
.logo {
background-color: #fbfbfb;
border-left: 1px #e9e9e9 solid;
border-top: 1px #e9e9e9 solid;
}
 
.page_name {
background-color: #fbfbfb;
border-right: 1px #e9e9e9 solid;
border-top: 1px #e9e9e9 solid;
font-size: 11px;
}
 
.menu_top {
background-color: #efefef;
border: 1px #e9e9e9 solid;
font-size: 11px;
}
 
.news {
background-color: #fbfbfb;
border: 1px #e9e9e9 solid;
font-size: 11px;
}
 
.menu {
background-color: #fbfbfb;
border: 1px #e9e9e9 solid;
font-size: 11px;
}
 
.center_left {
background-color: #fbfbfb;
border-left: 1px #e9e9e9 solid;
font-size: 11px;
}
 
.center_right {
background-color: #fbfbfb;
border-right: 1px #e9e9e9 solid;
font-size: 11px;
}
[HTML] pobierz, plaintext 

Pozdrawiam