design-themes/theme_buzzy/views/snippets/s_image_gallery.xml

<?xml version="1.0" encoding="utf-8"?>
<odoo>

<template id="s_image_gallery" inherit_id="website.s_image_gallery">
    <!-- Section -->
    <xpath expr="//section" position="attributes">
        <attribute name="class" add="o_full_screen_height pt56 pb56 o_cc o_cc2" remove="pt24 pb24" separator=" "/>
    </xpath>
</template>

<template id="s_images_wall" inherit_id="website.s_images_wall">
    <!-- Section -->
    <xpath expr="//section" position="attributes">
        <attribute name="class" add="pt48 pb48" remove="pt24 pb24" separator=" "/>
    </xpath>
</template>

</odoo>