package keyval error undefined color beamer

Question

When i compile the following code, i get the package keyval error, undefined code. Please help!

\documentclass{beamer}

\usepackage[frenchb]{babel}
\usepackage[T1]{fontenc}
\usepackage[latin1]{inputenc}
\usepackage{newcent}
\usepackage{color}

\usetheme{Warsaw}

\setbeamercolor{normal text}{teal}

\begin{document}

\begin{frame}

\setbeamertemplate{background canvas}[vertical shading][top=white,bottom=blue]
Texte n'ayant pas encore subi de changement de couleur.

\end{frame}

\end{document}

Answer 1

you have to use beamer colors, that is a foreground and background color:

\setbeamercolor{normal text}{fg=teal}