Manual for the tcolorbox package

3.2 Lower Part
/tcb/lowerbox=〈mode〉
(no default, initially visible)
Controls the treatment of the lower part of the box. Feasible values for 〈mode〉 are:
• visible: usual type setting of the lower part,
• invisible: empty space instead of the lower part contents,
• ignored: the lower part is not used (here).
The last two values are usually applied in connection with savelowerto.
\begin{tcolorbox}[lowerbox=invisible,colback=white]
This is a \textbf{tcolorbox}.
\tcblower
This is the lower part (but invisible).
\end{tcolorbox}
\begin{tcolorbox}[lowerbox=ignored,colback=white]
This is a \textbf{tcolorbox}.
\tcblower
This is the lower part (but ignored).
\end{tcolorbox}
This is a tcolorbox.
This is a tcolorbox.
/tcb/savelowerto=〈file name〉
(no default, initially empty)
Saves the content of the lower part in a file for an optional later usage.
\begin{tcolorbox}[lowerbox=invisible,savelowerto=\jobname_bspsave.tex,colback=white]
This is a \textbf{tcolorbox}.
\tcblower
This is the lower part which may be quite complex:
$\displaystyle f(x)=\frac{1+x^2}{1-x^2}$.
\end{tcolorbox}
Now, we load the saved text:\\
\input{\jobname_bspsave.tex}
This is a tcolorbox.
Now, we load the saved text:
This is the lower part which may be quite complex: f(x) = 1 + x2
1 − x 2 .
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