There is no need for any kind of (single or double) quotations:
… 'base' => $cat,
…
about quotations:
https://stackoverflow.com/questions/3446216/what-is-the-difference-between-single-quoted-and-double-quoted-strings-in-php
There is no need for any kind of (single or double) quotations:
… 'base' => $cat,
…
about quotations:
https://stackoverflow.com/questions/3446216/what-is-the-difference-between-single-quoted-and-double-quoted-strings-in-php