[cover-reg] Fix box to fit page margins

Author: tkoeppe

source/cover-reg.tex

@@ -2,6 +2,11 @@
 %%--------------------------------------------------
 %% Title page for the C++ Standard
 
+\setlength{\fboxsep}{1em}
+\newlength{\copyboxwidth}
+\setlength{\copyboxwidth}{\textwidth}
+\addtolength{\copyboxwidth}{-2\fboxsep}
+\addtolength{\copyboxwidth}{-2\fboxrule}
 
 \thispagestyle{empty}
 {\raisebox{.35ex}{\smaller\copyright}}\,ISO 2017 --- All rights reserved
@@ -28,23 +33,22 @@
 
 \vfill
 
-\begin{tabular}{|p{\hsize}|}
-\hline
+\fbox{%
+\begin{minipage}{\copyboxwidth}
+\vspace{1ex}
 \begin{center}
 \textbf{Warning}
 \end{center}
-
 \vspace{2ex}
 
 This document is not an ISO International Standard. It is distributed
 for review and comment. It is subject to change without notice and may
-not be referred to as an International Standard.\\\\
+not be referred to as an International Standard.\\[1em]
 
 Recipients of this draft are invited to submit, with their comments,
 notification of any relevant patent rights of which they are aware
-and to provide supporting documentation.\\\\
-\hline
-\end{tabular}
+and to provide supporting documentation.\\
+\end{minipage}}
 
 \vfill
 \noindent
@@ -55,11 +59,6 @@
 
 \thispagestyle{cpppage}
 
-\setlength{\fboxsep}{1em}
-\newlength{\copyboxwidth}
-\setlength{\copyboxwidth}{\textwidth}
-\addtolength{\copyboxwidth}{-2\fboxsep}
-\addtolength{\copyboxwidth}{-2\fboxrule}
 \fbox{%
 \begin{minipage}{\copyboxwidth}
 \vspace{1ex}