JSFiddle - React, Tailwind, and code Playground
HTML
<ul id="input_leistungen">
<li class='fieldwrapper' id='field'>
<div class='box'><input type='hidden' name='lid[]' class='fieldname' value='"+$(this).val()+"'/><span>"+$(this).text()+"</span><input type='button' class='remove' value='-' /></div></li>
<li class='fieldwrapper' id='field'>
<div class='box'><input type='hidden' name='lid[]' class='fieldname' value='"+$(this).val()+"'/><span>"+$(this).text()+"</span><input type='button' class='remove' value='-' /></div></li>
<li class='fieldwrapper' id='field'>
<div class='box'><input type='hidden' name='lid[]' class='fieldname' value='"+$(this).val()+"'/><span>"+$(this).text()+"</span><input type='button' class='remove' value='-' /></div></li>
</ul>
CSS
body { overflow: hidden; }
.box { width: 100px; height: 75px; background-color: #333; color: #ddd; margin: 10px; padding: 10px; border: 1px solid black}
.box:hover { cursor: move; border: 1px dotted red }
JavaScript
$(function () {
$('#input_leistungen').sortable();
})