# Make font of \subsubsection bold in amsart

I have the following code

\documentclass{amsart}

\makeatletter
\newcommand{\mainsectionstyle}{%
\renewcommand{\@secnumfont}{\bfseries}
\renewcommand\section{\@startsection{section}{2}%
\z@{.5\linespacing\@plus.7\linespacing}{-.5em}%
{\normalfont\bfseries}}%
}
\makeatother

\begin{document}
\mainsectionstyle
\section{klasdjklasd}
\subsection{daksdjasdj}
\subsubsection{adjklsjkasdjklas}
\end{document}

which produces

How do I change the italic font to bold font in the subsubsection? (Maybe also the font in the subsection, because it is by default bold)

• \renewcommand\subsubsection{\@startsection{section}{3}.... most likely – user31729 Aug 25 '16 at 16:16
• \renewcommand\subsubsection{\@startsection{subsubsection}{3}... indeed works. Did something wrong the first time I tried. – TheGeekGreek Aug 25 '16 at 16:20
• You may have to adjust some of the fontsize etc. and indentation parameters as well, but the main error is the wrong number after : 3 means subsection, 1 is section, 2 is subsection etc. And I meant \@startsection{subsubsection} actually -- sorry, I was too fast – user31729 Aug 25 '16 at 16:23
• Oh this is interesting. Did not know what the numbers mean. Thanks. – TheGeekGreek Aug 25 '16 at 16:24

## 1 Answer

easy to change the fonts for the sectioning commands; they're all independently defined.

from `amsart.cls':

\def\subsection{\@startsection{subsection}{2}%
\z@{.5\linespacing\@plus.7\linespacing}{-.5em}%
{\normalfont\bfseries}}
\def\subsubsection{\@startsection{subsubsection}{3}%
\z@{.5\linespacing\@plus.7\linespacing}{-.5em}%
{\normalfont\itshape}}

for \subsubsection, change \itshape to \bfseries.

you say "maybe also the font in the subsection, because if is by default bold", but you don't say what you want to change it to. in any event, it should be fairly obvious what to do -- replace \bfseries by whatever you want.

this change (and all similar definitions) should go in the preamble. they also need to be wrapped in \makeatletter ... \makeatother since they contain commands with @ as part of the name.

• I do not want to change the bold font of subsection, but I wanted to know how I could, since it works the same way as subsubsection and section. Thanks. Everything clear now. – TheGeekGreek Aug 25 '16 at 16:27