\documentclass{article}

\usepackage{amsmath, amsthm, amssymb, amsfonts}
\usepackage{thmtools}
\usepackage{graphicx}
\usepackage{setspace}
\usepackage{geometry}
\usepackage{float}
\usepackage{hyperref}
\usepackage[utf8]{inputenc}
\usepackage[english]{babel}
\usepackage{framed}
\usepackage[dvipsnames]{xcolor}
\usepackage{tcolorbox}
\usepackage{multicol} % for multiple columns

\colorlet{LightGray}{White!90!Periwinkle}
\colorlet{LightOrange}{Orange!15}
\colorlet{LightGreen}{Green!15}

\newcommand{\HRule}[1]{\rule{\linewidth}{#1}}

\declaretheoremstyle[name=Otázka]{thmsty}
\declaretheorem[style=thmsty,numberwithin=section]{theorem}
\tcolorboxenvironment{theorem}{colback=LightGray}

\declaretheoremstyle[name=Proposition,]{prosty}
\declaretheorem[style=prosty,numberlike=theorem]{proposition}
\tcolorboxenvironment{proposition}{colback=LightOrange}

\declaretheoremstyle[name=Principle,]{prcpsty}
\declaretheorem[style=prcpsty,numberlike=theorem]{principle}
\tcolorboxenvironment{principle}{colback=LightGreen}

\pagenumbering{gobble}
\setstretch{1.2}
\geometry{
    textheight=9in,
    textwidth=7in,
    top=0.5in,
    bottom=0.5in,
    left=0.5in,
    right=0.5in,
    headheight=12pt,
    headsep=25pt,
    footskip=30pt,
    landscape
}
\raggedbottom

% ------------------------------------------------------------------------------

\begin{document}

% ------------------------------------------------------------------------------
% Cover Page and ToC
% ------------------------------------------------------------------------------

\title{ \normalsize \textsc{}
        \\ [2.0cm]
        \HRule{1.5pt} \\
        \LARGE \textbf{\uppercase{PJV Sample Test __TEST_NUM__}
        \HRule{2.0pt} \\ [0.6cm]  \vspace*{10\baselineskip}}
        }

\maketitle

\newpage
