Beamer - Modifying the headline

Question

With beamer, I use the theme Montpellier, a sober theme giving basic navigational hints.

\usetheme{Montpellier}                 
\useinnertheme{default}
\useoutertheme{default}
\usecolortheme{default}             
\usefonttheme{professionalfonts}  

I would like to reduce the width of the separation lines. Can you help me to perform that task?

Answer 1

I'm not a great expert with Beamer but I think you need to change the lines in the file : beamerouterthemetree.sty

\begin{beamercolorbox}[wd=\paperwidth,colsep=1.5pt]{upper separation line head}
\end{beamercolorbox} 
 ...
\begin{beamercolorbox}[wd=\paperwidth,colsep=1.5pt]{lower separation line head}
\end{beamercolorbox} 

You can replace 1.5 pt by 0.8pt. A safe method is to copy this file inside the work folder or inside your texmf folder. Perhaps there is a setup macro in beamer to modify these values.