@RuthRTW add z-index to #customFloatingButton.
Updated Code Version (Replace this with old one)
<style>
#customFloatingButton {
position: fixed;
bottom: 10px;
right: 10px;
z-index: 999;
}
#customFloatingButton a {
display: inline-block;
background-color: #8ACB88;
color: white;
padding: 10px 10px;
text-decoration: none;
box-shadow: 0px 5px 10px -5px rgba(0,0,0,0.5);
transition: 200ms;
}
#customFloatingButton a:hover {
transform: scale(1.04);
}
</style>