JSFiddle - React, Tailwind, and code Playground
by steveukx
HTML
<span id="spanval" class="clickhere">1</span>
<input id="spanvalue" name="spanvalue" value="0" />
JavaScript
$('.clickhere').on('click', function() {
debugger;
var input = $('#spanvalue');
input.val( +input.val() + +this.innerHTML);
});