One big block with 2 smaller blocks aligned to it

Question

I want to align 2 blocks underneath one big one like this

 --------------------
|                    |
|                    |
 --------------------
 ---------  ---------
|         ||         |
|         ||         |
 ---------  ---------

For this example consider using the Berlin theme. Using columns doesn't align the boxes properly below the big one.

\documentclass{beamer}
\usetheme{Berlin}

\begin{document}

\begin{frame}{My Frame}
    \begin{block}{Block}
        Foo Bar  Foo Bar  Foo Bar  Foo Bar  Foo Bar  Foo Bar  Foo Bar  Foo Bar 
    \end{block}

    \begin{columns}
        \begin{column}{.48\textwidth}
            \begin{exampleblock}{Block}
            Foo Bar
            \end{exampleblock}
        \end{column}
        \begin{column}{.48\textwidth}
            \begin{block}{Block}
              Foo Bar
            \end{block} 
        \end{column}
    \end{columns}

\end{frame}

\end{document}

If nessesary I can add the whole template.

Answer 1

Inserting [totalwidth=1.02\textwidth] might do the trick

\documentclass{beamer}
\usetheme{Berlin}

\begin{document}

\begin{frame}{My Frame}
    \begin{block}{Block}
        Foo Bar  Foo Bar  Foo Bar  Foo Bar  Foo Bar  Foo Bar  Foo Bar  Foo Bar 
    \end{block}

    \begin{columns}[totalwidth=1.02\textwidth]
        \begin{column}{.47\textwidth}
            \begin{exampleblock}{Block}
            Foo Bar
            \end{exampleblock}
        \end{column}
        \begin{column}{.47\textwidth}
            \begin{block}{Block}
              Foo Bar
            \end{block} 
        \end{column}
    \end{columns}

\end{frame}

\end{document}