JSFiddle - React, Tailwind, and code Playground

HTML

<div id="container">
Before <span id="sample" style="font-family: monospace; -webkit-user-select:none">Test</span> After
</div>
<script>
// svg/dynamic-updates tests set enablePixelTesting=true, as we want to dump text + pixel results
if (self.testRunner)
    testRunner.dumpAsText(self.enablePixelTesting);
var description, debug, successfullyParsed, errorMessage;
(function() {
    function getOrCreate(id, tagName)
    {
        var element = document.getElementById(id);
        if (element)
            return element;
        element = document.createElement(tagName);
        element.id = id;
        var refNode;
        var parent = document.body || document.documentElement;
        if (id == "description")
            refNode = getOrCreate("console", "div");
        else
            refNode = parent.firstChild;
        parent.insertBefore(element, refNode);
        return element;
    }
    description = function description(msg, quiet)
    {
        // For MSIE 6 compatibility
        var span = document.createElement("span");
        if (quiet)
            span.innerHTML = '<p>' + msg + '</p><p>On success, you will see no "<span class="fail">FAIL</span>" messages, followed by "<span class="pass">TEST COMPLETE</span>".</p>';
        else
            span.innerHTML = '<p>' + msg + '</p><p>On success, you will see a series of "<span class="pass">PASS</span>" messages, followed by "<span class="pass">TEST COMPLETE</span>".</p>';
        var description = getOrCreate("description", "p");
        if (description.firstChild)
            description.replaceChild(span, description.firstChild);
        else
            description.appendChild(span);
    };
    debug = function debug(msg)
    {
        var span = document.createElement("span");
        getOrCreate("console", "div").appendChild(span); // insert it first so XHTML knows the namespace
        span.innerHTML = msg + '<br />';
    };
    var css =
        ".pass {" +
            "font-weight: bold;" +
       ...