Instead in making graphic lines, what code could I use?

<hr> makes a horizontal line
to make a virtical line you have to use a table such as
<TABLE WIDTH="100%" CELLPADDING=0>
<TR><TD WIDTH=1 BGCOLOR="000000">
<SPACER TYPE="block" WIDTH=1></TD>
<TD><P></P></TD></TR>
</TABLE>

and just edit the code as you would like it

http://www.lissaexplains.com/html5.shtml#lines

Vertical lines are just below that.