Perl, how to choose a directory

I'm trying to determine which of the content of a folder is a directory and which is a file, I wrote the following but the result is not what I would expect:

opendir DH, $dir or die "Cannot open Dir: $!";
my @dirs = grep !/^\.\.?$/, readdir DH ;
foreach my $files (@dirs) {
    print $files."<br>";
    if ( -d $files ) 
    {
        print $files." is a directory<br>";
    }
}
closedir DH;

The result is something as the example below:

.file1

file.log

file3.zip

file4

file5.zip

dir1.name1.suffix1.yyyy.MM.dd.hh.mm.ss

file5.zip

file6.tar

dir2

dir3.name1.suffix1.yyyy.MM.dd.hh.mm.ss

---

where the item starting with dir are actual directory, so my question is why the if is failing discover them as such? What am I doing wrong?