Hi Mikael,
I did not think about using Metapost, I tried with the keys of the command \framed without success.
I use the following code for my headings (thank you Aditya) and I would like to use your code instead.
Thank you.
Fabrice


\setupbackgrounds
    [header]
    [text]
    [frame=off,
     topframe=off,
     bottomframe=off,
     framecolor=,
     rulethickness=2pt]

  \defineframed
    [headerframed]
    [frame=off,
     height=fit,
     width=fit]

  \definecolor[ColorA][0.8(white)]
 

  \startsetups [headertext]

    \setupheadertexts
      [{\startframed [headerframed]
      [foregroundstyle=bold,background=color,backgroundcolor=ColorA]
      \getvariable{headertext}{title} n\high{o}\,\getvariable{headertext}{number}
      \stopframed}]

    \setupheadertexts
      [{\startframed [headerframed]
      [align=flushleft,foregroundstyle=]
       Lycée LA SALLE, Lille\\
       \getvariable{headertext}{location}\space\endash\space Mathématiques
       \stopframed}]
   
      [{\startframed [headerframed]
          [align=flushright,foregroundstyle=]
          \date[d=\getvariable{headertext}{day},m=\getvariable{headertext}{month},y=\getvariable{headertext}{year}]
          \stopframed}]

  \stopsetups

  \setvariable{headertext}{set}{\directsetup{headertext}}

\startuseMPgraphic{framewithshadow}
path p;
p:=origin--(OverlayWidth,0)--(OverlayWidth,OverlayHeight)--(0,OverlayHeight)--cycle;
fill p shifted (2,-2);
fill p withcolor 0.8white;
draw p;
setbounds currentpicture to p;
\stopuseMPgraphic

\defineoverlay[framewithshadow][\useMPgraphic{framewithshadow}]

\starttext
\setvariables
   [headertext]
   [title={Devoir maison},
    number={6},
    day={22},
    month={08},
    year={2019},
    location={Seconde B},
    time={}]
\framed[background=framewithshadow,offset=4bp]{\bf DM no 7 : Dérivation}
\stoptext



Le lun. 26 août 2019 à 11:31, Mikael P. Sundqvist <mickep@gmail.com> a écrit :
On Mon, Aug 26, 2019 at 10:25 AM Fabrice Couvreur <fabrice1.couvreur@gmail.com> wrote:
Hello,
How to make a frame with an offset shadow as the attached picture ? The text inside the frame is a variable.
Thank you.
Fabrice


frame.png

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Hi,

maybe something like this could work for you:

\startuseMPgraphic{framewithshadow}
path p;
p:=origin--(OverlayWidth,0)--(OverlayWidth,OverlayHeight)--(0,OverlayHeight)--cycle;
fill p shifted (2,-2);
fill p withcolor 0.7white;
draw p;
setbounds currentpicture to p;
\stopuseMPgraphic

\defineoverlay[framewithshadow][\useMPgraphic{framewithshadow}]

\starttext
\framed[background=framewithshadow,offset=4bp]{\bf DM no 7 : Dérivation}
\stoptext

/Mikael 
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maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
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archive  : https://bitbucket.org/phg/context-mirror/commits/
wiki     : http://contextgarden.net
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