\documentclass[modern, footercenter, infoblock, lang=english]{onlinebrief24}

\setfromfirstname{Jane}
\setfromlastname{Smith}
\setfromaddress{12 Oak Street | Bristol BS1 4DJ}
\setfromlandline{0123 / 456 788}
\setfromphone{0123 / 456 789}
\setfromemail{jane.smith@example.com}
\setfromweb{www.example.com}
\setfromlinkedin{jane-smith}

\setreturnaddress{Jane Smith, 12 Oak Street, Bristol BS1 4DJ}
\setrecipient{Example Services Ltd \\ Mr. John Smith \\ 24 Market Road \\ London SW1A 1AA}

\setsubject{A test of the new modern style}
\setplace{Bristol}
\setdate{\today}
\setyourref{INF-2026-17}
\setyourmessage{2026-03-17}
\setourref{OB24-2042}
\setcontactname{Jane Smith}
\setcontactphone{0123 / 456 789}
\setcontactemail{brief@example.com}

\begin{document}
\begin{letter}{}
    \opening{Dear Mr. Smith,}
    
    This is an example letter that demonstrates the new
    \texttt{modern} option of the \texttt{onlinebrief24.cls} class.
    
    As you can see, my name appears in a large modern heading at the top
    right, followed by the new information block and the contact details in
    the footer.
    
    Most importantly, the position of the address window and the sender line
    remains exactly the same as in the standard layout.
    
    \closing{Kind regards}
\end{letter}
\end{document}