center subsection

layout.sty

@@ -517,7 +517,7 @@ interior code={ \path[tcb fill interior] ([xshift=-2mm]interior.west)
 \renewcommand*{\thesection}{\arabic{section}}
 
 \titleformat{\subsection}
-{\needspace{7em}\normalfont\large\bfseries}{\thesubsection}{1em}{}[\titlerule\vspace{1ex}\setcounter{list}{0}]
+{\needspace{7em}\normalfont\center\large\bfseries}{\thesubsection}{1em}{}[\titlerule\vspace{1ex}\setcounter{list}{0}]
 
 %
 \titleformat{\subsubsection}