Aligning matrix within a matrix (beamer, inside item number)

Question

I tried to make 16 2x2 matrices inside a large matrix but somehow it does not look nice because:

1. The space between left bracket of large matrix and left bracket of small matrix on the left side is too tight and the space between right bracket of large matrix and right bracket of small matrix on the right side is too wide.
2. There is almost no vertical space between smaller matrix.

Is there any fix for this?

MWE

\documentclass{beamer}
  \usetheme{default}     
  \usecolortheme{default}
  \usefonttheme{default}
  \setbeamertemplate{navigation symbols}{}
  \setbeamertemplate{caption}[numbered]
} 

\usepackage[english]{babel}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{amsmath}

\begin{document}

\begin{frame}

\begin{block}{Algoritma}
    \begin{enumerate}
        \item
            \begin{vmatrix}
\begin{vmatrix} a & \cdots \\ \cdots & \cdots \end{vmatrix} &
\begin{vmatrix} a & \cdots \\ \cdots & \cdots \end{vmatrix} &
\begin{vmatrix} a & \cdots \\ \cdots & \cdots \end{vmatrix} &
\begin{vmatrix} a & \cdots \\ \cdots & \cdots \end{vmatrix} &
\\ 
\begin{vmatrix} a & \cdots \\ \cdots & \cdots \end{vmatrix} &
\begin{vmatrix} a & \cdots \\ \cdots & \cdots \end{vmatrix} &
\begin{vmatrix} a & \cdots \\ \cdots & \cdots \end{vmatrix} &
\begin{vmatrix} a & \cdots \\ \cdots & \cdots \end{vmatrix} &
\\ 
\begin{vmatrix} a & \cdots \\ \cdots & \cdots \end{vmatrix} &
\begin{vmatrix} a & \cdots \\ \cdots & \cdots \end{vmatrix} &
\begin{vmatrix} a & \cdots \\ \cdots & \cdots \end{vmatrix} &
\begin{vmatrix} a & \cdots \\ \cdots & \cdots \end{vmatrix} &
\\ 
\begin{vmatrix} a & \cdots \\ \cdots & \cdots \end{vmatrix} &
\begin{vmatrix} a & \cdots \\ \cdots & \cdots \end{vmatrix} &
\begin{vmatrix} a & \cdots \\ \cdots & \cdots \end{vmatrix} &
\begin{vmatrix} a & \cdots \\ \cdots & \cdots \end{vmatrix} &
\end{vmatrix}
    \end{enumerate}
\end{block}

\end{frame}

\end{document}

Answer 1

You can avoid the problems by using a tblr from the tabularray package:

\documentclass{beamer}
%  \usetheme{default}     
%  \usecolortheme{default}
%  \usefonttheme{default}
  \setbeamertemplate{navigation symbols}{}
  \setbeamertemplate{caption}[numbered]
%} 

\usepackage[english]{babel}
%\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
%\usepackage{amsmath}

\usepackage{tabularray}
\UseTblrLibrary{amsmath}
\begin{document}

\begin{frame}

\begin{block}{Algoritma}
    \begin{enumerate}
        \item
            \begin{tblr}{
              colspec={|llll|},
              cells={mode=imath}
            }
\begin{+vmatrix} a & \cdots \\ \cdots & \cdots \end{+vmatrix} &
\begin{+vmatrix} a & \cdots \\ \cdots & \cdots \end{+vmatrix} &
\begin{+vmatrix} a & \cdots \\ \cdots & \cdots \end{+vmatrix} &
\begin{+vmatrix} a & \cdots \\ \cdots & \cdots \end{+vmatrix} &
\\
\begin{+vmatrix} a & \cdots \\ \cdots & \cdots \end{+vmatrix} &
\begin{+vmatrix} a & \cdots \\ \cdots & \cdots \end{+vmatrix} &
\begin{+vmatrix} a & \cdots \\ \cdots & \cdots \end{+vmatrix} &
\begin{+vmatrix} a & \cdots \\ \cdots & \cdots \end{+vmatrix} &
\\
\begin{+vmatrix} a & \cdots \\ \cdots & \cdots \end{+vmatrix} &
\begin{+vmatrix} a & \cdots \\ \cdots & \cdots \end{+vmatrix} &
\begin{+vmatrix} a & \cdots \\ \cdots & \cdots \end{+vmatrix} &
\begin{+vmatrix} a & \cdots \\ \cdots & \cdots \end{+vmatrix} &
\\
\begin{+vmatrix} a & \cdots \\ \cdots & \cdots \end{+vmatrix} &
\begin{+vmatrix} a & \cdots \\ \cdots & \cdots \end{+vmatrix} &
\begin{+vmatrix} a & \cdots \\ \cdots & \cdots \end{+vmatrix} &
\begin{+vmatrix} a & \cdots \\ \cdots & \cdots \end{+vmatrix} &
\end{tblr}
    \end{enumerate}
\end{block}

\end{frame}

\end{document}