'next and previous section' buttons

(mobile portrait only)

Hi everybody,

I have a fixed navbar with a right arrow and a left arrow. I want the right arrow to go to the next section and the left arrow to go to the previous section.

I found this script but I just don’t get it to work. Do is mis something?

<script>
$('.PUT_YOUR_CLASS_HERE').click(function(){
$.fn.fullpage.moveSectionDown(); 
});
$('.PUT_YOUR_CLASS_HERE').click(function(){
$.fn.fullpage.moveSectionUp(); 
});
</script>

Here is my site Read-Only: https://preview.webflow.com/preview/marked-design?utm_medium=preview_link&utm_source=designer&utm_content=marked-design&preview=9e86539844e5e1967cdfc861e37ffa2e&workflow=preview