\mode<presentation>

\setbeamercolor*{sidebar}{parent=block title}
\setbeamercolor{local structure}{parent=sidebar}
\setbeamercolor{section in toc}{parent=sidebar}

\setbeamercolor{button}{use=structure,bg=structure.fg!50!bg,fg=white}

\setbeamercolor{block title alerted}{use=sidebar,fg=sidebar.fg!25!red}
\setbeamercolor{block title example}{use=sidebar,fg=sidebar.fg!50!green}

\setbeamercolor*{title}{parent=structure}

\setbeamersize{text margin left=1.5ex}
\setbeamersize{text margin right=1.5ex}
\setbeamersize{sidebar width left=.25\paperwidth}
\setbeamersize{description width=0pt}
\setlength\leftmargini{0pt}
\setlength\leftmarginii{1.5ex}
\setlength\leftmarginiii{1.5ex}

\newenvironment{beamer@nomargin}{%
  \hskip-.20\paperwidth%
  \begin{beamercolorbox}[wd=0.9\paperwidth]{sidebar}%
    \setlength{\linewidth}{0.88\paperwidth}%
}{%
  \end{beamercolorbox}%
}

\newcommand\beamer@putleft[2]{%
  \hbox to 0pt{\hss\vtop{%
      \normalsize%
      \@tempdima=.25\paperwidth%
      \advance\@tempdima by-3ex%
      \hsize=\@tempdima%
      \leftskip=0pt plus 1fill%
      \rightskip=0pt\relax%
      \leavevmode#1}\kern#2}%
}
\newenvironment{beamer@putright}{\vtop\bgroup\leavevmode}{\egroup}

\defbeamertemplate*{section in toc}{inmargin}
{
  \leavevmode%
  \beamer@putleft{\usebeamercolor[fg]{section in sidebar}\inserttocsectionnumber\strut}{2.5ex}%
  \beamer@putright%
  \inserttocsection%
  \endbeamer@putright
}

\defbeamertemplate*{subsection in toc}{inmargin}
{\leavevmode%
  \inserttocsubsection\par\vskip.5ex}

\defbeamertemplate*{subsubsection in toc}{inmargin}
{\leavevmode%
  \inserttocsubsubsection\par\vskip.5ex}


\def\inserttitleindicator{}
\def\insertauthorindicator{Who?}
\def\insertinstituteindicator{From?}
\def\insertdateindicator{When?}

\defbeamertemplate*{title page}{inmargin}
{
  \begin{block}{\inserttitleindicator}
    \usebeamercolor[fg]{title}\usebeamerfont{title}\inserttitle\par
    \usebeamercolor[fg]{subtitle}\usebeamerfont{subtitle}\insertsubtitle
  \end{block}
  \vfill
  \ifx\insertauthor\@empty
  \else
  \begin{block}{\insertauthorindicator}
    \usebeamercolor[fg]{author}\usebeamerfont{author}\insertauthor\par
  \end{block}
  \fi
  \ifx\insertinstitute\@empty
  \else
  \begin{block}{\insertinstituteindicator}
    \usebeamercolor[fg]{institute}\usebeamerfont{institute}\insertinstitute\par
  \end{block}
  \fi
  \ifx\insertdate\@empty
  \else
  \begin{block}{\insertdateindicator}
    \usebeamercolor[fg]{date}\usebeamerfont{date}\insertdate\par
  \end{block}
  \fi
}

\defbeamertemplate*{block begin}{inmargin}
{
  \par\vskip\medskipamount%
  \leavevmode%
  \beamer@putleft{\normalfont{\usebeamercolor[fg]{block title}\usebeamerfont*{block title}\insertblocktitle}}{2.5ex}%
  \beamer@putright\usebeamercolor[fg]{block body}%
  \usebeamerfont{block body}%
  \ifbeamercolorempty[bg]{block body}{\vskip-1.75ex}{\vskip-2ex}%
  \begin{beamercolorbox}[colsep*=.70ex,vmode]{block body}%
    \ifbeamercolorempty[bg]{block body}{}{\vskip-.25ex}%
}

\defbeamertemplate*{block end}{inmargin}
{
    \ifbeamercolorempty[bg]{block body}{}{\vskip-.25ex}%
  \end{beamercolorbox}%
  \endbeamer@putright\vskip\smallskipamount%
}

\defbeamertemplate*{block alerted begin}{inmargin}
{
  \par\vskip\medskipamount%
  \leavevmode%
  \beamer@putleft{\normalfont{\usebeamercolor[fg]{block title alerted}\usebeamerfont*{block title alerted}\insertblocktitle}}{2.5ex}%
  \beamer@putright\usebeamercolor{block body alerted}%
  \usebeamerfont{block body alerted}%
  \ifbeamercolorempty[bg]{block body alerted}{\vskip-1.75ex}{\vskip-2ex}%
  \begin{beamercolorbox}[colsep*=.70ex,vmode]{block body alerted}%
    \ifbeamercolorempty[bg]{block body alerted}{}{\vskip-.25ex}%
}
\defbeamertemplate*{block alerted end}{inmargin}
{
    \ifbeamercolorempty[bg]{block body}{}{\vskip-.25ex}%
  \end{beamercolorbox}%
  \endbeamer@putright\vskip\smallskipamount%
}

\defbeamertemplate*{block example begin}{inmargin}
{
  \par\vskip\medskipamount%
  \leavevmode%
  \beamer@putleft{\normalfont{\usebeamercolor[fg]{block title example}\usebeamerfont*{block title example}\insertblocktitle}}{2.5ex}%
  \beamer@putright\usebeamercolor{block body example}%
  \usebeamerfont{block body example}%
  \ifbeamercolorempty[bg]{block body example}{\vskip-1.75ex}{\vskip-2ex}%
  \begin{beamercolorbox}[colsep*=.70ex,vmode]{block body example}%
    \ifbeamercolorempty[bg]{block body example}{}{\vskip-.25ex}%
}
\defbeamertemplate*{block example end}{inmargin}
{
    \ifbeamercolorempty[bg]{block body}{}{\vskip-.25ex}%
  \end{beamercolorbox}%
  \endbeamer@putright\vskip\smallskipamount%
}

\AtBeginDocument
{
  \addtobeamertemplate{enumerate item}{\llap\bgroup}{\normalsize\kern1.5ex\egroup}
  \addtobeamertemplate{enumerate subitem}{\llap\bgroup}{\normalsize\kern1.5ex\kern\leftmarginii\egroup}
  \addtobeamertemplate{enumerate subsubitem}{\llap\bgroup}{\normalsize\kern1.5ex\kern\leftmarginii\kern\leftmarginiii\egroup}
  \addtobeamertemplate{itemize item}{\llap\bgroup}{\normalsize\kern1.5ex\egroup}
  \addtobeamertemplate{itemize subitem}{\llap\bgroup}{\normalsize\kern1.125ex\kern\leftmarginii\egroup}
  \addtobeamertemplate{itemize subsubitem}{\llap\bgroup}{\small\kern0.75ex\kern\leftmarginii\kern\leftmarginiii\egroup}
  \addtobeamertemplate{description item}{\llap\bgroup\usebeamercolor[fg]{section in sidebar}\small}{\kern1.125ex\egroup}
}

\mode
<all>