design-themes/theme_loftspace/views/snippets/s_features.xml

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

<template id="s_features" inherit_id="website.s_features">
    <!-- First column : icon -->
    <xpath expr="//div[hasclass('row')]//div//i" position="attributes">
        <attribute name="class" add="bg-o-color-3" remove="bg-o-color-1" separator=" "/>
    </xpath>
    <!-- Second column : icon -->
    <xpath expr="//div[hasclass('row')]//div[2]//i" position="attributes">
        <attribute name="class" add="bg-o-color-3" remove="bg-o-color-5" separator=" "/>
    </xpath>
    <!-- Third column : icon -->
    <xpath expr="//div[hasclass('row')]//div[3]//i" position="attributes">
        <attribute name="class" add="bg-o-color-3" remove="bg-o-color-2" separator=" "/>
    </xpath>
</template>

</odoo>