Add minimalistic Cookie Notice

cookie-notice.php

<?php function cookie_notice(){?>

<p id="cookie-notice"><span>By visiting our website, you accept use of cookies and agree to <a href="/privacy-policy/" target="_blank" style="color:#001947!important;">privacy policy</a>.</span><button onclick="acceptCookie();" class="md-cookie-button">Accept</button></p>
<style>#cookie-notice{display:flex;align-items:center;left:50%;transform:translateX(-50%);font-family:inherit;font-size:15px;background:#ffffff; color:#001947; padding:10px 20px;position:fixed;bottom:10px;box-shadow:0 10px 20px rgba(0,0,0,.2);border-radius:3px;margin:0px;visibility:hidden;z-index:1000000;box-sizing:border-box}#cookie-notice button{color:#ffffff;background:#001947;border:0;padding:5px 10px;cursor:pointer;font-size:inherit;margin-left:10px;border-radius:3px}@media only screen and (max-width:800px){#cookie-notice{flex-direction:column;width:100%;bottom:0;left:0;border-radius:0;transform:none;text-align:center}#cookie-notice button{margin:10px 0px 0px 0px}}</style>
<script>function acceptCookie(){document.cookie="cookieaccepted=1; expires=Sun, 1 Jan 2045 12:00:00 UTC; path=/",document.getElementById("cookie-notice").style.visibility="hidden"}document.cookie.indexOf("cookieaccepted")<0&&(document.getElementById("cookie-notice").style.visibility="visible");</script>

<?php }

add_action('wp_footer','cookie_notice'); ?>

Replace wp_footer with md_hook_after_footer_copy if you are using Marketers Delight theme.

What to change?
Nothing much but you can change the colors to match your site's aesthetics and date of Cookie Expiration. Be sure to use correct date format as coded on line #5.