JSFiddle - React, Tailwind, and code Playground

HTML

<a href="login"  title="log in" class="login_button" id="tst">Login</a></span>

JavaScript

var prom = getCookie('prom');
if (prom === '0') 
{
if (document.getElementById('tst')){
var str=document.getElementById("tst").innerHTML;
var n=str.replace("Login","Logout");
 document.getElementById("tst").innerHTML=n;
    setCookie('prom','1',1);}}






function setCookie(c_name, value, exdays) {
    var exdate = new Date();
    if (exdays) exdate.setDate(exdate.getDate() + exdays);
    var c_value = escape(value) + ((exdays) ? '; expires=' + exdate.toUTCString() : '');
    document.cookie = c_name + "=" + c_value;
}

function getCookie(name) {
    var re = new RegExp(name + "=([^;,]+)");
    var value = re.exec(document.cookie);
    return (value !== null) ? unescape(value[1]) : null;
}