\setupbodyfont
  [dejavu,8pt]

\dontcomplain

\setuptolerance
  [verytolerant,stretch]

\setuplayout
  [backspace=1cm,
   width=middle]

\starttext

\setupmixedcolumns
  [boxedcolumns]
  [n=2,
   background=color,
   backgroundcolor=darkred,
   color=white,
   backgroundoffset=1mm]

\definemixedcolumns
  [nestedboxedcolumns]
  [boxedcolumns]
  [n=2,
   background=color,
   backgroundcolor=white,
   color=darkred,
   strut=yes,
   backgroundoffset=0mm]

\startboxedcolumns
    \input zapf \par \input ward \par \obeydepth
    \startnestedboxedcolumns
        \input zapf
    \stopnestedboxedcolumns
    \par \input zapf \par \obeydepth
    \startnestedboxedcolumns
        \input zapf
    \stopnestedboxedcolumns
    \par \input zapf
\stopboxedcolumns

\stoptext
