Hello,
The best way is using as start the code from portfolio-extra-pagination.html page. If you are using another pictures + filter code (from another page) and wants to implement the pagination, this way will not works.
Please try starting from the code of mentioned extra pagination page and make sure you are adding the following scripts on footer of page (like in the example link):
<script src="vendor/bootpag/jquery.bootpag.min.js"></script>
<script src="js/examples/examples.portfolio.js"></script>
Please try that and let us know if you need further assistance.
Kind Regards,
Rodrigo.
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