JSFiddle - React, Tailwind, and code Playground

HTML

<script async
  src="https://cse.google.com/cse.js?cx=000888210889775888983:g9ckaktfipe"></script>

<div class="gcse-searchbox"></div>

<div class="gcse-searchresults"></div>

JavaScript

SearchResultsRenderedCallback = function(){

var elements = document.getElementsByClassName('gs-title');
for (var i = 0; i < elements.length; i++) {
  var element = elements[i];
  element.style.fontSize = "24px";
}

};

window.__gcse || (window.__gcse = {});
window.__gcse.searchCallbacks = {
  web: {
      rendered: SearchResultsRenderedCallback,
  },
};