#!/usr/bin/perl

use strict;
use warnings;

use CSS;

my $css_data = do{ local $/; <DATA> };

my $css = CSS->new();

$css->read_string( $css_data );

foreach my $style ( @{ $css->{ styles } } ) {
	foreach my $selector ( @{ $style->{ selectors } } ) {
		print $selector->{ name } . "\n";
	}
}

__DATA__

.selector_one {
    margin-left: 1em;
}

.selector_two,
.selector_three {
    margin-left: 1em;
}