# color in beamer theme

I want to create a representation like this, I use Hannover theme but I can't find the color

The presentation you show in your image most likely uses a background image for the sidebar. If you just want a similar colour, you can change the sidebar colour and the colour of most structural elements like this:

\documentclass{beamer}

\definecolor{myblue}{RGB}{39,75,133}
\usecolortheme[named=myblue]{structure}
\usetheme{Hannover}
\setbeamercolor{sidebar}{bg=myblue}

\begin{document}

\begin{frame}
\frametitle{Plan}
\tableofcontents
\end{frame}

\section{section name}
\begin{frame}
\frametitle{title}
abc
\end{frame}

\end{document}