To make a gradient animation background span between multiple sections, you can follow these steps
#1. Suppose you need to do this for Section 1, Section 2, and Section 3.
First, you need to edit 3 Sections > Add Code block on each section > Paste this code
<span class="span-section"></span>

#2. Add this code to the Custom CSS box and click Save
/* Span gradient animation background between sections */
.span-section-parent {
& {
background: linear-gradient(-45deg, #ee7752, #e73c7e, #23a6d5, #23d5ab);
background-size: 400% 400%;
animation: gradient 15s ease infinite;
}
.section-background, .section-border, section {
background-color: transparent !important;
}
}
@keyframes gradient {
0% {
background-position: 0% 50%;
}
50% {
background-position: 100% 50%;
}
100% {
background-position: 0% 50%;
}
}

#3. Add this code to Code Injection > Footer
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.7.0/jquery.min.js"></script>
<script>
$(document).ready(function() {
$('.code-block .span-section').closest('section.page-section').addClass('span-section');
$('section.span-section').wrapAll('<section class="span-section-parent"></section>');
});
</script>
