title: R Markdown (beamer) - how to create 2 columns
body: <p>I am trying to create a presentation using RMarkdown beamer. I want a slide to have 2 columns and this is what I have so far:</p>
  <pre><code>---
  title: title
  
  author: name
          
  date: date
  
  output:
    beamer_presentation:
      theme: Szeged
      slide_level: 2
      includes:
        in_header: header.tex
      keep_tex: true
  
  linkcolor: false
  ---
      
  ## TEST
  
  \footnotesize
  \justify
  :::::::::::::: {.columns}
  ::: {.column}
  - I will write something here tex text text tex text text tex text text
  :::
  ::: {.column}
  - And then something here tex text text tex text text tex text text tex text text
  :::
  ::::::::::::::
  </code></pre>
  <p>The header.tex's content is:</p>
  <pre><code>\definecolor{mycolorlightblue}{RGB}{103,153,200}
  \definecolor{mycolordarkblue}{RGB}{0,70,127}
  % add packages
  \usepackage{tikz}
  \usetikzlibrary{arrows}
  \usepackage{tcolorbox}
  \usepackage{ragged2e}
  % remove 2nd section from header
  \makeatletter
  \beamer@theme@subsectionfalse
  \makeatother
  % change colour of lines
  \setbeamercolor{separation line}{bg=mycolorlightblue}
  % text title
  \setbeamercolor{title}{fg=mycolordarkblue}
  \setbeamercolor{frametitle}{fg=mycolordarkblue}
  % text colour
  \setbeamercolor{frametitle}{fg=mycolordarkblue}
  % item colour
  \setbeamercolor{structure}{fg=mycolordarkblue}
  % define colour text
  % \usebeamerfont{section title}\color{blue!70!green}\insertsection\par
  % no header or footer on first page
  \thispagestyle{empty}
  % remove title slides at beginning of sections
  \AtBeginSection{}
  % add page counter to the footer
  \setbeamertemplate{footline}[frame number]
  % logo of my university
  \titlegraphic{%
    \begin{picture}(0,0)
      \put(155,0){\makebox(0,0)[rt]{\includegraphics[]{ALL-ICONS.png}}}
    \end{picture}}
  </code></pre>
  <p>This is the result I am seeing, almost perfect, but the 2nd column starts slight below the first one, as shown below, do you understand why?</p>
  <p><a href="https://i.stack.imgur.com/JY7bT.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/JY7bT.png" alt="enter image description here" /></a></p>
  <p>correspondent .tex file to the .rmd:</p>
  <pre><code>\begin{frame}{TEST}
  \protect\hypertarget{test}{}
  
  \footnotesize
  \justify
  
  \begin{columns}[T]
  \begin{column}{0.48\textwidth}
  \begin{itemize}
  \tightlist
  \item
    I will write something here text text text text text text text text
    text text text text text text text
  \end{itemize}
  \end{column}
  
  \begin{column}{0.48\textwidth}
  \begin{itemize}
  \tightlist
  \item
    And then something here text text text text text text text text text
    text text text text text text
  \end{itemize}
  \end{column}
  \end{columns}
  
  \end{frame}
  </code></pre>