[texhax] Colour selection in beamer

[Sam Albers]

Hello TeXhax!

I am having a little beamer problem that I can't seem to figure out.
The below example should illustrate my problem. I want to change the
text colour of the selected section/subsection to black instead of
white as the white is difficult to see. This example should run. Has
anyone ever attempted to change those colours before?

Thanks so much in advance!

Sam

%% Code

\documentclass{beamer}[14pt]
\usepackage{beamerthemesplit}


%% I want to use this pre-defined colour
\definecolor{customgreen}{cmyk}{0.95,0.15,0.62,0.58}
\mode<presentation>


\usetheme{Goettingen}
\setbeamertemplate{footline}[frame number]
\setbeamertemplate{headline}{}

\setbeamertemplate{navigation symbols}{}
  \usecolortheme[named=customgreen]{structure}
  \useinnertheme{circles}
  \usefonttheme[onlymath]{serif}
  \setbeamertemplate{blocks}[rounded][shadow=false]
\setbeamersize{sidebar width right=1.9cm}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\begin{document}
\section{Heading}
\begin{frame}
  \frametitle{Test}
\end{frame}
\subsection{Sub-head}
\begin{frame}
  \frametitle{Sub-head is difficult to see}
Could the text colour of the sub-heading be changed to black?
\end{frame}


\end{document}