Maybe CSS::Tiny is what you want: 
use CSS::Tiny;

my $string = do {local $/; <DATA>};
my $css = CSS::Tiny->read_string($string);

$\ = "\n";
print for keys %$css;
__DATA__

.selector_name {
    margin-left: 1em;
}

[download]

--shmem 

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

In reply to Re: Extracting a list of selectors from a css file by shmem
in thread Extracting a list of selectors from a css file by wfsp

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