Close, but you are missing a closing bracket - change:

$q->p( "Your method of payment is ",
$q->span({-style=>"color:blue"},$pay_text),
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to (indented for clarity)

$q->p("Your method of payment is ",
  $q->span({-style=>"color:blue"},$pay_text)
),
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map{$a=1-$_/10;map{$d=$a;$e=$b=$_/20-2;map{($d,$e)=(2*$d*$e+$a,$e**
2-$d**2+$b);$c=$d**2+$e**2>4?_:0}1..99;print$c}0..59;print$/}0..20;
[download]