Validazione BackgroundColor Warning...

[ricman]

Ho questa serie di Warning nella validazione del Css (Dtd=html strict).
Perchè? Ad esempio, la Line 3 (vedi sotto) il background ce l'ha!!

html, body {
  margin: 0px 0px 0px 0px;
  background-color: #ffffff;
  padding: 0px;
  text-align: center;
}

Questi sono i Warning...

    * Line : 3 (Level : 1) You have no color with your background-color : body
    * Line : 10 (Level : 1) You have no background-color with your color : h4
    * Line : 10 (Level : 1) You have no background-color with your color : h4
    * Line : 10 (Level : 1) You have no background-color with your color : h4
    * Line : 10 (Level : 1) You have no background-color with your color : h4
    * Line : 10 (Level : 1) You have no background-color with your color : h4
    * Line : 10 (Level : 1) You have no background-color with your color : h4
    * Line : 10 (Level : 1) You have no background-color with your color : h4
    * Line : 10 (Level : 1) You have no background-color with your color : h4
    * Line : 10 (Level : 1) You have no background-color with your color : h4
    * Line : 10 (Level : 1) You have no background-color with your color : h4
    * Line : 10 (Level : 1) You have no background-color with your color : h4
    * Line : 10 (Level : 1) You have no background-color with your color : h4
    * Line : 10 (Level : 1) You have no background-color with your color : h4
    * Line : 10 (Level : 1) You have no background-color with your color : h4
    * Line : 10 (Level : 1) You have no background-color with your color : h4
    * Line : 10 (Level : 1) You have no background-color with your color : h4
    * Line : 10 (Level : 1) You have no background-color with your color : h4
    * Line : 34 (Level : 1) You have no color with your background-color : #main
    * Line : 42 (Level : 1) You have no color with your background-color : #head
    * Line : 60 (Level : 1) You have no background-color with your color : #sx
    * Line : 88 (Level : 1) You have no background-color with your color : #footer a
    * Line : 93 (Level : 1) You have no background-color with your color : a.credits
    * Line : 99 (Level : 1) You have no color with your background-color : #menu
    * Line : 135 (Level : 1) You have no background-color with your color : #menu a
    * Line : 153 (Level : 1) You have no background-color with your color : h1
    * Line : 163 (Level : 1) You have no background-color with your color : h2
    * Line : 179 (Level : 1) You have no background-color with your color : a

[thomas_anderson]

I warning non sono errori, ma dei semplici avvertimenti (appunto) dati per favorire l'accessibilità delle pagine. puoi ignorarli tranqullamente, perchè se dessimo retta a quello che dicono, le nostre pagine diverrebbero un accozzaglia multicolore in cui ogni elemento ha un color ed un background diverso. quello che essere considerato è invece il contrasto di colore fra le parti, come stabilito dal W3C. in questo senso puoi scaricare Colour Contrast Analyzer (lo trovi con Google su Webaccessibile)del W3C. ciao