body   { background:#887766 url(leberwurst.jpg) 0px 0px fixed no-repeat; background-size: 100% auto; padding-left:5%; font-family:sans-serif; }

#einleitung,#loesung,#lsg { padding:2%; max-width:55em; border:solid 1px #000077; }
#einleitung { background:#ccffdd; color:#000033; }
#loesung    { background:#ffffcc; color:#330000; }
#lsg        { background:#ccddee; color:#003300; }