Floating button

Look at the bottom-right corner — a fixed “☕ Tip” pill. Click it to open the tip widget in a popover. On a narrow screen the label collapses to just the icon and the panel becomes a bottom sheet. Scroll around; it stays put.

<script src="/widget.js"
        data-creator="Bilal"
        data-currency="gbp"
        data-amounts="3,5,10"
        data-placement="floating"
        data-position="bottom-right"></script>

Set data-position="bottom-left" to move it to the other corner.