diff --git a/report.tex b/report.tex
index c96e231..5dd3742 100644
--- a/report.tex
+++ b/report.tex
@@ -256,7 +256,7 @@
           inner sep=2pt
         },
         std/.style={sys, fill=blue!8},
-        fo/.style={sys, fill=red!10, very thick},
+        fo/.style={sys, fill=red!10},
         rel/.style={->, thick},
         weak/.style={->, semithick, dashed},
         equv/.style={<->, thick, dotted}