if($Background eq "#Rot")
{
  $Background="#FFD9D9";
}elsif($Background eq "#blau")
{
$Background="#xxxxxx";
}elsif($Background eq "#Gelb")
{
$Background="#yyyyyy"; 
}else{
## standart, wenn nichts angegeben ist
$Background="#wwwwww"; 
}

        Blau=>"#xxxxxx",
        Gelb=>"#zzzzzz");
$Background=$farbe{$Background};