Tikz : alignement de nodes
Dans une frame, j'aimerais que les nodes (ligne du bas) soient alignés horizontalement par le haut, et non centrés comme ils le sont.
\documentclass{beamer}
\usepackage{tikz}
\begin{document}
\frame{
\frametitle{Occupation du site de Bibracte}
\begin{tikzpicture}[scale=.68,every node/.style={scale=.68}]
\tikzstyle{quadri}=[rectangle,draw,fill=white]
\tikzset{quadri}=[rectangle,draw,fill=white]
\tikzset{case/.style={text width=3cm,text centered}}
% Cases
\node[case] (Ed) at (0,4) {\large\textbf{Éduens}};
\node[case-c] \node[case] (Opp) at (0,0) {\large\textbf{Oppidum de Bibracte}};
\node[case-c] \node[case] (Acc) at (-6,-4) {\large\textbf{Voies d'accès}};
\node[case-c] \node[case] (Gis) at (-2,-4) {\large\textbf{Gisements de minerais}};
\node[case-c] \node[case] (Eau) at (2,-4) {\large\textbf{Présence d'eau}};
\node[case-c] \node[case] (Def) at (6,-4) {\large\textbf{Altitude du site: défense naturelle}};
% Flèches
\draw[-stealth,line width=5pt,blue] (Ed) to (Opp);
\draw[-stealth,line width=5pt,blue] (Opp) to (Acc);
\draw[-stealth,line width=5pt,blue] (Opp) to (Gis);
\draw[-stealth,line width=5pt,blue] (Opp) to (Eau);
\draw[-stealth,line width=5pt,blue] (Opp) to (Def);
\end{tikzpicture}
}
\end{document}
