How do you dull notes without damping the strings with your left hand (for right handed player)?

For e.g.:
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In the intro she gets a dull sound from the 2 and 3rd strings. How do I get that sound? It doesn't look like she's damping the strings with her left hand.

Thanks for your help in advance.

And I might add that the closer your palm is to the bridge, the "clearer" the muted note becomes, and the further your palm is from the bridge, the "duller" the note gets. Basically, you have a great deal of control over your tone depending on where and how hard you palm mute.
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Hey. Thanks for the responses. It does look like she is muting them with her palm. But I what didn't understand was how she was selectively muting the 2nd and 3rd strings with a broad surface like her palm. But it looks like she's muting all the strings and just letting the first string ring.