\begin{block}{HEADER}
text
\end{block}
The HEADER comes in a dark-blue background. How can I change it? I
have checked the manual and could not figure out how to do it. Thanks,
Oz.
Change the beamer color "block title", in particular the background.
HTH
Ulrich
Can you please be more specific, which command you are referring to.
Following your advice, I have tried:
\begin{block}{\colorbox{green}{HEADER}}
text.
\end{block}
Well the header now has a green background, but only around the text,
so it looks odd?
Thanks again for your help, Oz.
\documentclass{beamer}
\setbeamercolor{block title}{bg=red}
\begin{document}
\begin{block}{HEADER}
text
\end{block}
\end{document}
U.