\setbeamertemplate{footline}
{
	\begin{beamercolorbox}[wd=1.0\textwidth,ht=3ex,dp=1.5ex,leftskip=.5em,rightskip=.7em]{author in head/foot}
	\usebeamerfont{author in head/foot}
	\color{grau}{\hfill\insertframenumber{} / \inserttotalframenumber}
	\end{beamercolorbox}
}