\usetheme{default}
\usepackage{color}

\usepackage{texnansi}			%Remove these two lines
\usepackage{gtamacgillsans}		%if you don't have gtamac fonts

\definecolor{bottomcolour}{rgb}{0.32,0.3,0.38}
\definecolor{middlecolour}{rgb}{0.08,0.08,0.16}
\setbeamerfont{title}{size=\Huge}
\setbeamercolor{structure}{fg=white}
\setbeamertemplate{frametitle}[default][center]

\setbeamercolor{normal text}{bg=black, fg=white}
\setbeamertemplate{background canvas}[vertical shading]
[bottom=bottomcolour, middle=middlecolour, top=black]

\setbeamertemplate{itemize item}{\lower3pt\hbox{\Large\textbullet}}
\setbeamerfont{frametitle}{size=\huge}