# How to use thmtool to defined a bolded theorem style?

I am currently following this answer to create a theorem style using theorem tool. How to change the way theorems are displayed?

Previously I used something from the amsthm package, but it had a major conflict with my template, therefore all my precious theorem styles were destroyed

The style I am looking for looks like this:

Does anyone know how to change the line "\declaretheoremstyle[headfont=\scshape,postheadspace=\newline]{mystyle}" to generate the theorem style I want?

• Could you be clearer about the style that you want? Removing the \headfont = \scshape will make it Serif.
– Troy
Mar 19, 2017 at 2:17
• Is that a template one can download somewhere? If it is related to the question, you should give a link. Right now, the question should not be tagged [tempaltes], so i'll remove the tag. Mar 19, 2017 at 14:02

Like this?

\documentclass{book}
\usepackage{fourier}
\usepackage{mathtools}
\usepackage{amsthm, thmtools}
\usepackage{cleveref}
%
\declaretheoremstyle[%
bodyfont =\itshape,
spaceabove = 8pt,spacebelow = 8pt]%
{mythmstyle}

\declaretheorem[style=mythmstyle]{Theorem}

\begin{document}

\setcounter{chapter}{3}
Some text. Some text. Some text. Some text. Some text. Some text. Some text. Some text. Some text. Some text. Some text.
\begin{Theorem}\label{testthm}
The following assertion is true: %
$$a = a$$
\end{Theorem}

We see in \cref{testthm}

\end{document}