[JAVASCRIPT] Aide dans menu dynamique

posYmenu = 126;
bgcolor='#000000';
bgcolor2='#4b6f90';
needcenter =false;
if(!needcenter)
 posXmenu = ???;
else
 { if (document.all)
  posXmenu = (document.body.clientWidth/2)-(500/2);
 else
  posXmenu = (window.innerWidth/2)-(500/2);  
 }
document.write('<style type="text/css">');
document.write('.popper { POSITION: absolute; VISIBILITY: hidden; z-index:3; }')
document.write('#topgauche { position:absolute; top:'+posYmenu+'px; left:'+posXmenu+'px; z-index:10; }')
document.write('A:hover.ejsmenu {color:#FC9925; text-decoration:none;}')
document.write('A.ejsmenu {color:#FC9925; text-decoration:none;}')
document.write('</style>')
 
document.write('<DIV class=popper id=topdeck></DIV>')