How can I modify the following headline to make the letters bigger

Question

I have the following code

\documentclass[10pt]{beamer}
\graphicspath{{./Figures/}}
\usetheme[progressbar=frametitle]{metropolis}
\setbeamercolor{progress bar}{fg=orange,bg=green}

\makeatletter
\setbeamertemplate{headline}
{%
  \begin{beamercolorbox}[ht=3.5ex,dp=1.125ex,%
      leftskip=.3cm,rightskip=.3cm plus1fil]{section in head/foot}
    \usebeamerfont{section in head/foot}\usebeamercolor[fg]{section in head/foot}%
    \insertsectionhead
  \end{beamercolorbox}%
  \begin{beamercolorbox}[colsep=1.5pt]{middle separation line head}
  \end{beamercolorbox}
  \begin{beamercolorbox}[ht=2.5ex,dp=1.125ex,%
    leftskip=.3cm,rightskip=.3cm plus1fil]{subsection in head/foot}
    \usebeamerfont{subsection in head/foot}\insertsubsectionhead
  \end{beamercolorbox}%
  \begin{beamercolorbox}[colsep=1.5pt]{lower separation line head}
  \end{beamercolorbox}
}
\makeatother

\setbeamercolor{section in head/foot}{fg=normal text.bg, bg=structure.fg}

Which I have copied from the answer to this question

I have generated two slides as

\section{Introduction}
\subsection{Subsection}

\begin{frame}{Introduction}

    \begin{center}
    I have text here
    \end{center}

\end{frame}

I have on the top left of the second slide the section and subsection, but the text is too small. I have tried to change all the numbers in the first block of text, but I have just moved the text, not changed its size.

Please, can someone tell me how to make Introduction and subsection larger in the slide? I am not too familiar with beamer.

Answer 1

You could change the (sub-)section in head/foot font like this:

\documentclass[10pt]{beamer}
\graphicspath{{./Figures/}}
\usetheme[progressbar=frametitle]{moloch}% modern fork of the metropolis theme
\setbeamercolor{progress bar}{fg=orange,bg=green}

\makeatletter
\setbeamertemplate{headline}
{% 
  {\usebeamerfont{section in head/foot}
  \begin{beamercolorbox}[ht=3.5ex,dp=1.125ex,%
      leftskip=.3cm,rightskip=.3cm plus1fil]{section in head/foot}
    \usebeamercolor[fg]{section in head/foot}%
    \insertsectionhead
  \end{beamercolorbox}}%
  \begin{beamercolorbox}[colsep=1.5pt]{middle separation line head}
  \end{beamercolorbox}
  {\usebeamerfont{subsection in head/foot}
  \begin{beamercolorbox}[ht=2.5ex,dp=1.125ex,%
    leftskip=.3cm,rightskip=.3cm plus1fil]{subsection in head/foot}
    \insertsubsectionhead
  \end{beamercolorbox}}%
  \begin{beamercolorbox}[colsep=1.5pt]{lower separation line head}
  \end{beamercolorbox}
}
\makeatother

\setbeamercolor{section in head/foot}{fg=normal text.bg, bg=structure.fg}

\setbeamerfont{section in head/foot}{size=\small}
\setbeamerfont{subsection in head/foot}{size=\small}

\begin{document}


\section{Introduction}
\subsection{Subsection}

\begin{frame}{Introduction}

    \begin{center}
    I have text here
    \end{center}

\end{frame}


\end{document}