I define a custom footline template like that:
\setbeamertemplate{footline}{
\hspace*{.5cm}
\includegraphics[scale=0.07]{images/image1.png}
\hspace{0.3cm}
\scriptsize{Seite \insertframenumber}
\hfill
\includegraphics[scale=0.25]{images/image2.png}
\hspace*{.5cm}
\vspace{9pt}
}
How can I also define a background color for the whole footline? I want the footline to be light grey...