在`tabularray`的`X[c,m]`格式下，如何合并单元格？

也可以用你自己用的syntax:cell{}{}={}{}

\documentclass{article}
\usepackage{xcolor}
\usepackage[scale=0.8,papersize={10.5cm,14.85cm}]{geometry}
\usepackage{tabularray}
\pagestyle{empty}
\begin{document}
\begin{center}
    \begin{tblr}{
        hlines,vlines,
        colspec={X[c,m]X[c,m]X[c,m]X[c,m]X[c,m]X[c,m]},
        % cell{3,4}{4,5}={bg=green!30},
        % cell{3,4}{6}={bg=red!30},
        % cell{5,6,7}{6}={bg=blue!30},
        cell{3}{4} = {r=2,c=2}{c,m,bg=green!30},
        cell{3}{6} = {r=2,c=1}{c,m,bg=red!30},
        cell{5}{6} = {r=3,c=1}{c,m,bg=blue!30},
        % stretch = 0,%
    }
        1-1&1-2&1-3&1-4&1-5&1-6\\
        2-1&2-2&2-3&2-4&2-5&2-6\\
        3-1&3-2&3-3&3-4&   &3-6\\
        4-1&4-2&4-3&   &   &   \\
        5-1&5-2&5-3&5-4&5-5&5-6\\
        6-1&6-2&6-3&6-4&6-5&   \\
        7-1&7-2&7-3&7-4&7-5&   \\
    \end{tblr}
\end{center}
\end{document}

多读读文档，其实是有现成的例子抄的~