\mode<presentation>

\useoutertheme{split}
\useinnertheme{rectangles}
\usecolortheme{GATE}

\setbeamercolor*{titlelike}{parent=structure}

% make frame numbers optional (but enabled by default)
\newif\ifframenumbers
\framenumberstrue

% Change the footline to also include the frame number if enabled
\expandafter\def\expandafter\insertshorttitle\expandafter{%
  \insertshorttitle \ifframenumbers\hfill \insertframenumber\,/\,\inserttotalframenumber\fi%
}

\mode
<all>
