JSFiddle - React, Tailwind, and code Playground

HTML

<button onClick="setCookie('law_cookie', 'agree_all', 90)">Save cookie</button><br/>
<button onClick="showCookies()">Show cookies</button><br/>
<textarea id=cookies></textarea>

JavaScript

function setCookie(name, value, daysToLive) {
    // Encode value in order to escape semicolons, commas, and whitespace
    let cookie = name + "=" + encodeURIComponent(value);

    if (typeof daysToLive === "number") {
        /* Sets the max-age attribute so that the cookie expires
        after the specified number of days */
        cookie += ";max-age=" + (daysToLive * 24 * 60 * 60) + ';path=/';

				window.alert(cookie);
        document.cookie = cookie;
        cookie_set = true
    }
}

function showCookies() {
  const output = document.getElementById('cookies')
  output.textContent = '> ' + document.cookie
}