Style and edit the 'CONTINUE SHOPPING' button

I am really struggling to find the location on the site to edit this button below. Does anyone know either where I can find these settings or help me out with the CSS to edit it.

I'd like it to be bigger and match the rest of the site's buttons which are black with a rounded corner.

https://www.stlukes.ie/cart

Thanks so much!

It is following the Secondary Button Styling, or you have this CSS on your website:

#siteWrapper.site-wrapper .sqs-button-element--secondary {
    padding: 0em 0.9em;
}

The padding is set to zero top and bottom.