\mode<presentation> 
% Requirement
\RequirePackage{tikz}

\setbeamertemplate{background}{
    \begin{tikzpicture}
        \definecolor{utokyo-blue}{HTML}{187fc3};
        \definecolor{utokyo-yellow}{HTML}{f9be00};
        \useasboundingbox (0,0) rectangle(\the\paperwidth,\the\paperheight);
        \ifnum\insertframenumber>0\relax%
            \fill[white,opacity=1] (0,0) rectangle(\the\paperwidth,\the\paperheight);
            \node [below left] at (\the\paperwidth, \the\paperheight - 5mm) 
                    {\includesvg[height = 1.2 cm]{./images/UTokyo_Logo.svg}};
            \node [above] at (0.7, 0) 
                    {\includesvg[height = 1.5 cm]{./images/clocktower.svg}};
            \node[below right] at (current bounding box.north west) {
                \footnotesize
                \hspace{.05\paperwidth} 
                {
                    \ifx\SUBTITLE\@empty
                        \tiny\inserttitle~| \insertshortauthor~| \insertdate
                    \else
                        \tiny\inserttitle~ -- \insertsubtitle~| \insertshortauthor~| \insertdate
                    \fi
                }};
            \node[above left] at (current bounding box.south east) {
                    {\large\insertframenumber}
                };
            \fill[color=utokyo-yellow] (0.5,1.7) rectangle(.9,\the\paperheight);
        \else 
            \node [above left] at (\the\paperwidth,0) 
            {\includesvg[height=.3\paperheight]{./images/UTokyo_Logo_small.svg}};
        \fi
    \end{tikzpicture}
}

% Title page
\defbeamertemplate*{title page}{utokyo}[1][]
{ 
    \begin{center}
        \Large
        \textbf{\inserttitle}\\
        \ifx\SUBTITLE\@empty
            \else
                \large
                \insertsubtitle\\
            \fi
        \ifx\TITLEIMAGE\@empty
            \else
                \TITLEIMAGE\\
            \fi
        \normalsize
        \insertauthor\\
        \insertdate
    \end{center}
}

\mode <all>