%%
%% The LaTeX Companion, 3ed
%%
%% Example 8-4-13 on page I-620 in "Skins and styles --- altering the look and feel".
%%
%% Copyright (C) 2022 Frank Mittelbach
%%
%% It may be distributed and/or modified under the conditions
%% of the LaTeX Project Public License, either version 1.3c
%% of this license or (at your option) any later version.
%%
%% See https://www.latex-project.org/lppl.txt for details.
%%

\documentclass{tlc3exa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{135.0pt}
\usepackage[skins]{tcolorbox}
  \tcbset{top=0pt,middle=0pt,bottom=0pt} % shorten the example

  \AtBeginDocument{\scriptsize}

%StartShownPreambleCommands

%StopShownPreambleCommands

\begin{document}
\begin{tcolorbox}[empty,title=The empty skin,coltitle=blue]
  By default the title would be white on \tcblower
  white, hence the adjustment!
\end{tcolorbox}
\end{document}
