# tcolorbox: sidebyside inner margins

When using sidebyside, the right part of the tcolorbox do not seem to honor the margins.

Consider:

\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage[most]{tcolorbox}
\usepackage{lipsum}
%\tcbuselibrary{skins}

\newtcolorbox{EmR}{%
sidebyside,sidebyside align=top,lower separated=true,lefthand width=0.4em,
arc=8pt,
boxsep=0pt,
left=8pt,right=2pt,top=2pt,bottom=2pt,
fontupper=\Large\bfseries\rm,
fontlower=\small,
after=\smallskip,
skin=bicolor,
colback=black!60, colframe=black!60,
colupper=white,
colbacklower=white,boxrule=0.5pt,
}

\begin{document}

\begin{EmR}
R
\tcblower
\lipsum[1]
\end{EmR}

\end{document}


(I would like to reduce the space in blue to reflect my margins.)

Bonus point: Do you guys have any suggestions as to how to have more margin between the "R" and the frame (without increase the margin for the part at the right?)

You can adjust lefthand width=1.5em, and use sidebyside gap=2pt, to get

I don't think I understand the bonus question properly. It means probably this:

\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage[most]{tcolorbox}
\usepackage{lipsum}
%\tcbuselibrary{skins}

\newtcolorbox{EmR}{%
sidebyside,sidebyside align=top,lower separated=true,lefthand width=1.8em,
arc=8pt,
boxsep=0pt,
left=8pt,right=2pt,top=2pt,bottom=2pt,
fontupper=\Large\bfseries\rmfamily,
fontlower=\small,
after=\smallskip,
skin=bicolor,
colback=black!60, colframe=black!60,
colupper=white,
colbacklower=white,boxrule=0.5pt,
sidebyside gap=2pt,
}

\begin{document}

\begin{EmR}
\raisebox{-1ex}{R}
\tcblower
\lipsum[1]
\end{EmR}

\end{document}


If the upper part has only one letter like R, then the following is also possible:

\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage[most]{tcolorbox}
\usepackage{lipsum}
%\tcbuselibrary{skins}

\newtcolorbox{EmR}[1][]{%
arc=8pt,
boxsep=0pt,
left=3em,,right=2pt,top=2pt,bottom=2pt,
fontupper=\small,
after=\smallskip,
skin=bicolor,
colback=white,colframe=black!60,
boxrule=0.5pt,
overlay={\begin{tcbclipinterior}
\draw[black!60,line width=6em-4pt] (interior.north west)--(interior.south west);
\node[font=\Large\bfseries\rmfamily, text=white, anchor=north west, inner ysep=5pt, minimum width=3em]
at (frame.north west) {#1};
\end{tcbclipinterior}
}
}

\begin{document}

\begin{EmR}[R]
\lipsum[1]
\end{EmR}

\end{document}


Adjust left=3em,, line width=6em-4pt (6em=2 times the left margin and 4pt = 2 times the right margin), inner ysep=5pt, minimum width=3em (minimum width=left).

• Very complete. Hopefully it will be hopeful to others as well. Thank you :) – Ricardo Cruz Sep 18 '15 at 17:34