Hi, I'm doing a fit of node with tikz but somehow can't manage to remove the separation between fit and the inner nodes... Any hint?
\begin{tikzpicture}[line width=.5pt,every node/.style={anchor=center,minimum width=.75cm,minimum height=.75cm}]
\matrix (m) [matrix of nodes,nodes in empty cells,row sep=0cm,column sep=0cm]{
& & & & &\\
& & |[fill=green]|AC & |[fill=yellow]|DC & AC & DC\\
& DC & & & & \\
& AC & & & & \\
& DC & & & & \\
& AC & & & & \\
};
\node[fill=blue,fit={(m-1-3) (m-1-4)},line width=.5pt,inner sep=0pt,label=center:{$U_s$}] {};