customization of section with tikz and titlesec

Question

i'm trying to customize the title of sections in my document using the packages tikz and titlesec.

Unfortunately, that does not work and i need some help to solve my problem.

I get this error :

! Argument of \tikz@next has an extra }.
<inserted text>
\par
l.25 \section{Problem}
I've run across a `}' that doesn't seem to match anything.

Here is my code :

\documentclass[a4paper, 11pt]{article}
\usepackage[francais]{babel}    
\usepackage[utf8]{inputenc}     
\usepackage[T1]{fontenc}        

\usepackage{titlesec}           
\usepackage[x11names]{xcolor}   
\usepackage{tikz}
\titleformat{\section}
    {\normalfont\Large\sffamily\bfseries\color{CadetBlue4}}
    {%
        \tikz[anchor=base,baseline,outer sep=0pt]               
        \node[anchor=base,rectangle,rounded corners,fill=CadetBlue4]
        {\normalfont\Large\sffamily\bfseries{\textcolor{CadetBlue2!20}{\thesection}}};%
    }{0em}{}

\begin{document}
\tikz[anchor=base,baseline,outer sep=0pt]
\node[anchor=base,rectangle,rounded corners,fill=CadetBlue4]
{\normalfont\Large\sffamily\bfseries{\textcolor{CadetBlue2!20}{That works}}};

\section{Problem}

\end{document}

Thank you for your help.

Answer 1

It ran fine for me too, but you can try the following simpler code to get the same result with tcolorbox (which anyway relies on tikz):

\documentclass[a4paper, x11names, 11pt]{article}
\usepackage[francais]{babel}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{tcolorbox}
\usepackage{titlesec}

\titleformat{\section}
    {\normalfont\Large\sffamily\bfseries\color{CadetBlue4}}
    {\tcbox[colback=CadetBlue4, colframe=CadetBlue4, coltext=CadetBlue2!20, on line, boxsep=0pt, left=4pt, right=4pt, top=4pt, bottom=4pt]{\thesection}}{0.2em}{}

\begin{document}

\section{Problem}

\end{document}