# How do I increase the inmargin in beamer?

I would like to do two things

1. Increase the size of inmargin area (i.e., customize inner sidebar so that more contents could fit there)
2. Reduce the empty space between the title of block environment and the slide edge (from the example below, the title of block has too much of wasted space to its left which could be used to create more readable sentences)

MWE

\documentclass[xcolor={x11names}]{beamer}

\usecolortheme{structure}
\useinnertheme{rectangles}
\useinnertheme{inmargin}

\usecolortheme{crane}

\usefonttheme{structurebold}

\usepackage{fontspec}

\usepackage{calc}

\usepackage[inline]{enumitem}
% Description list defaults

% To change font
\newcommand{\descriptionfont}{\fontencoding{T1} \fontfamily{bch} \selectfont}

% Label indentation
\newcommand{\descLabOffset}{\widthof{\hspace{2.6mm}}}

% Left of description aligned with the left margin
\newcommand{\descLeftLabMarInd}{0mm - \descLabOffset}

% Left of description aligned with \parindent
\newcommand{\descLeftLabParInd}{\parindent - \descLabOffset}

% Set the list options
\setlist[description, 1]{font=\descriptionfont, leftmargin=*, labelsep=3mm, labelindent=\descLeftLabMarInd, align=left}

\begin{document}

\begin{frame}{Induction Motors}

\begin{block}{Why is induction motor very common?}

Induction motors are very practical for the following reasons

\begin{description}
\item[Rigid] Rigid
\item[Cheap] Cheap
\item[Low Maintenance] Low Maintenance
\item[Self-Starting] Self-starting
\item[No Excitation Needed] No Excitation Needed
\end{description}

\end{block}

\end{frame}

\end{document}


## 1 Answer

The width of the inmargin can be changed with \setbeamersize{sidebar width left=.5\paperwidth}. Unfortunately the width of the block title is hard coded, but with the following redefinition the width can be adjusted:

\documentclass{beamer}

\useinnertheme{inmargin}
\usecolortheme{crane}

\setbeamersize{sidebar width left=.5\paperwidth}

\makeatletter
\renewcommand\beamer@putleft[2]{%
\hbox to 0pt{\hss\vtop{%
\normalsize%
\@tempdima=\beamer@leftsidebar%
\advance\@tempdima by-3ex%
\hsize=\@tempdima%
\leftskip=0pt plus 1fill%
\rightskip=0pt\relax%
\leavevmode#1}\kern#2}%
}
\makeatother

\begin{document}

\begin{frame}{Induction Motors}

\begin{block}{Why is induction motor very common?}

Induction motors are very practical for the following reasons

\begin{description}
\item[Rigid] Rigid
\item[Cheap] Cheap
\item[Low Maintenance] Low Maintenance
\item[Self-Starting] Self-starting
\item[No Excitation Needed] No Excitation Needed
\end{description}

\end{block}

\end{frame}

\end{document}


Off-topic: don't use enumitem with beamer, beamer has its own mechanism to control the appearance of items.

EDIT:

I opened a PR to automatically adapt the text width to match the width of the sidebar (https://github.com/josephwright/beamer/pull/529). Until this is fixed, you can get a patched version of the theme from https://github.com/samcarter/beamer/blob/c9672255bd7cfe45d67ff63e2305d48c213766d2/base/themes/inner/beamerinnerthemeinmargin.sty