JSFiddle - React, Tailwind, and code Playground

HTML

<div class="bottom" id="alert">
  this website use cookies
  <button onclick="accpetCookie()">
    click here for accpet cookie
  </button>
</div>
<div class="scroll">
  website content
</div>

CSS

.bottom {
  position: fixed;
  bottom: 0;
  width: 100%;
  background: #ccc;
  color: #fff
}

.scroll {
  min-height: 1500px;
}

JavaScript

if (getCookie('accepted') === 'yes') {
  document.getElementById("alert").style.display = "none";
}

function accpetCookie() {
  setCookie('accepted', 'yes', 100);
}

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

function getCookie(c_name) {
  var i, x, y, ARRcookies = document.cookie.split(";");
  for (i = 0; i < ARRcookies.length; i++) {
    x = ARRcookies[i].substr(0, ARRcookies[i].indexOf("="));
    y = ARRcookies[i].substr(ARRcookies[i].indexOf("=") + 1);
    x = x.replace(/^\s+|\s+$/g, "");
    if (x == c_name) {
      return unescape(y);
    }
  }
}