% https://tex.stackexchange.com/q/369065/ \documentclass{article} \usepackage{xsim,tcolorbox,needspace} \xsimsetup{ exercise/within=section , exercise/the-counter = \thesection.\arabic{exercise} , exercise/template=cyan-box , exercise/name=Example , solution/template=red , solution/print=true } \DeclareExerciseEnvironmentTemplate{cyan-box} {% \begin{tcolorbox}[arc=0mm,boxrule=1pt,colback=white,colframe=cyan,leftrule=3mm] \textsf{% \MakeUppercase{% \XSIMmixedcase{\GetExerciseName}~\GetExerciseProperty{counter}% }% }% \GetExercisePropertyT{subtitle}{ \textit{#1}}% \quad } {\end{tcolorbox}} \DeclareExerciseEnvironmentTemplate{red} {% \par \Needspace*{2\baselineskip} \noindent \textsf{\textcolor{red}{\MakeUppercase{\XSIMmixedcase{\GetExerciseName}}}}% \quad } {\par\bigskip} \begin{document} \section{My first set of exercises} \begin{exercise} Prove that $\frac{1}{2}\Delta(f_{ij}f^{ij}) =\nabla^{k}f^{ij}+f^{ij}f^{k}[2\nabla_{i}R_{jk}-\nabla_{k}R_{ij}]$ \end{exercise} \begin{solution} From \dots \end{solution} \begin{exercise} Prove that Paulinho is smart. \end{exercise} \begin{solution} All ducks are smart. Paulinho is a duck. Therefore, Paulinho is smart. \end{solution} \begin{exercise} Prove that Paulinho is smart. \end{exercise} \begin{solution} All ducks are smart. Paulinho is a duck. Therefore, Paulinho is smart. \end{solution} \section{My second set of exercises} \begin{exercise} Prove that Paulinho is smart. \end{exercise} \begin{solution} All ducks are smart. Paulinho is a duck. Therefore, Paulinho is smart. \end{solution} \begin{exercise} Prove that Paulinho is smart. \end{exercise} \begin{solution} All ducks are smart. Paulinho is a duck. Therefore, Paulinho is smart. \end{solution} \end{document}