diff --git a/slides_template/example.tex b/slides_template/example.tex
index c1a4193..76a7d32 100644
--- a/slides_template/example.tex
+++ b/slides_template/example.tex
@@ -43,9 +43,9 @@
 }
 
 % more flexible non-tikz alternative with no dropshadow 
+\newlength{\centertxtlen}
+\makeatletter
 \newcommand\centertext[2]{%
-  \newlength{\centertxtlen}
-  \makeatletter
   \setlength{\centertxtlen}{#1}%
   \setlength{\centertxtlen}{0.35\centertxtlen}%
   {\centering