JSFiddle - React, Tailwind, and code Playground

HTML

<button class="theme-toggle" data-theme="default">Default</button>
<button class="theme-toggle" data-theme="dark">Dark</button>
<button class="theme-toggle" data-theme="light">Light</button>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

CSS

body[theme="default"] {
  background-color: #ccc;
}

body[theme="dark"] {
  background-color: #333;
}

body[theme="light"] {
  background-color: #fff;
}

JavaScript

(function ($) {
  var $body = $('body');
  var loadTheme = function () {
    $body.attr('theme', localStorage.getItem('theme') || 'default');
  };
  $('.theme-toggle').click(function () {
    localStorage.setItem('theme', $(this).data('theme'));
    loadTheme();
  });
  loadTheme();
} (jQuery));