\NeedsTeXFormat{LaTeX2e}[1994/06/01]
\ProvidesClass{istcim}[2020/09/20 1.0.0 ISTCiM class]

%% Article options
\DeclareOption{10pt}{
  \PassOptionsToClass{\CurrentOption}{article}
}
\DeclareOption{11pt}{
  \PassOptionsToClass{\CurrentOption}{article}
}
\DeclareOption{12pt}{
  \PassOptionsToClass{\CurrentOption}{article}
}

\ExecuteOptions{10pt}

\ProcessOptions\relax

\LoadClass[a4paper]{article}

\RequirePackage{graphicx}
\RequirePackage{amsmath}
\RequirePackage{amssymb}

\RequirePackage[utf8]{inputenc}
\RequirePackage{enumerate}

%% specific commands and options 

\usepackage[hmargin=30mm, vmargin=15mm, hcentering, vcentering]{geometry}
\setlength{\parindent}{0pt}


\newcounter{prob}
\setcounter{prob}{0}

\newcounter{theor}[prob]
\setcounter{theor}{0}

\newcommand\university[1]{\def\@university{#1}}

\newenvironment{problem}[1][\theprob]{\vspace{6pt} \par \refstepcounter{prob} \noindent{\textbf{Problem~#1} [\textit{Proposed by}: \@author \textit{ from}: \@university]} \\* \indent }{\vspace{8pt} \par }
\newenvironment{solution}[1][{}]{\par \vspace{6pt}\hrulefill \par\vspace{6pt}\par \noindent{\textbf{Solution#1:}} \\* \indent }{\hfill $\Box$ \vspace{18pt}\par }
\newenvironment{proclaim}[1][Theorem]{\vspace{6pt} \par \refstepcounter{theor} \noindent{\textbf{#1~\thetheor}}\it \\* \indent }{\vspace{18pt} \rm \par }
\newenvironment{remark}{\par \noindent{\textbf{Remark}}\it \par }{\vspace{8pt} \rm \par }
\newenvironment{lemma}[1][{}]{\vspace{6pt} \par \refstepcounter{theor} \noindent{\textbf{Lemma~\thetheor} \textsc{#1}} \it \par }{\vspace{6pt} \rm \par }
\newenvironment{theorem}[1][\theprob.\thetheor]{\vspace{6pt} \par \refstepcounter{theor} \noindent{\textbf{Theorem~\thetheor} \textsc{#1}} \it \par }{\vspace{6pt} \rm \par }
\newenvironment{proof}{\par \noindent{\textsl{Proof:}} }{\par\ \hfill  $\diamond$\vspace{8pt}\par }

\endinput