JSFiddle - React, Tailwind, and code Playground
HTML
<div id="div1">
<ul>
<li data-item="11"></li>
<li data-item="12"></li>
<li data-item="13"></li>
<li data-item="14"></li>
</ul>
</div>
<ul id="div2">
</ul>
<div id = "button">fake button</div>
JavaScript
$("#button").on("click", function(){
var item = $("div li").each(function(){
return $(this).filter('[data-item]');
});
if (item.attr("data-item") <= 12){
x.appendTo("#div2");
}
});