JSFiddle - React, Tailwind, and code Playground
HTML
<div>
<input type="text" class="mariinsky" /><button id="inside">+</button>
</div>
<button id="outside">Button</button>
<br />
input value = <span></span>
JavaScript
$( '.mariinsky' ).on('keypress keyup keydown click copy cut paste', function() {
var bolshoi = jQuery( ".mariinsky" ).val();
jQuery( 'span' ).text(bolshoi);
});