JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://code.jquery.com/jquery-3.2.1.min.js"></script>
<div class="slide active">
  <p>Тут</p>
</div>

JavaScript

function pasternak() {
  var $peshki = $(".slide.active p");
  if ($peshki.length > 0) {
    console.log("I FIND IT");
  } else {
    console.log("TRY AGAIN!");
  }
}
pasternak();