It seems there is an iframe added by Stripe to this page which causes extra padding on the bottom of the page.
You can use the CSS editor to customize the appearance of the Hypermarket theme. It works by allowing you to add your own CSS styles, which allows you to override the default styles of the theme.
To access the CSS editor, first launch your site customizer then click on the Additional CSS tab to access the CSS editor.
margin-bottom: 0 !important;
padding-bottom: 0 !important;