Your definition for @allColors should use " instead of ' in order for the escape sequences to be interpreted with meaning.

i.e.

my @allColors = "\e[48;5;1m  \e[48;5;2m  \e[48;5;3m  \e[48;5;4m  \e[48;5;5m".words;

The escape characters are encoded in a string when the string is first evaluated.

e.g.

my $notNewline = '\n';
my $newline = "\n";
print "Foo $newline Bar $notNewline"

will output Foo ␤ Bar \n even though the $notNewline is printed using "