look_down works on html attributes, width is a css attribute 
#!/usr/bin/perl --

use strict;
use warnings;

use HTML::TreeBuilder;

my $html = '<html><body>
<span style="height:128px;width:160px">bob</span>
</body></html>';

my $tree = HTML::TreeBuilder->new();
$tree->parse( $html );
print $tree->look_down('style',qr/\Q128px;width:160px\E/i)->dump;

__END__
<span style="height:128px;width:160px"> @0.1.0
  "bob"

[download]

In reply to Re^2: How to use regex in Tree->look_down by Anonymous Monk
in thread How to use regex in Tree->look_down by corpx

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