floating window code

Dear friends, let me ask you a question. (Sorry in advance for my poor English)

On one of the source sites, I found the floating window code.

I tried it by creating a primitive html page and it turned out to be quite a working code that I would happily use in my PrestaShop site. I would like to bind a phone number to it, perhaps viber ...

Perhaps you will need it too.

But, after downloading the code and saving it, it simply disappears.

As I understand it, again, it is connected with the setting of the presta. I do not approve, but I would like to run it on the prest.

If you can help dear advice I will be very grateful to you. Does anyone know the best approach to this? (I repeat that after loading and saving it simply disappears) Perhaps it needs to be loaded in the wrong place or in some other way?

Here is the code friends.

<meta name=\"viewport\" content=\"width=device-width, initial-scale=1\">

<style>

body {font-family: Arial, Helvetica, sans-serif;}

.callout {

  position: fixed;

  bottom: 10px;

  right: 10px;

  margin-left: 10px;

  max-width: 200px;

}

.callout-header {

  padding: 25px 15px;

  background: #555;

  font-size: 30px;

  color: white;

}

.callout-container {

  padding: 15px;

  background-color: #ccc;

  color: black

}

.closebtn {

  position: absolute;

  top: 5px;

  right: 15px;

  color: white;

  font-size: 30px;

  cursor: pointer;

}

.closebtn:hover {

  color: lightgrey;

}

</style>

<h2>Callout Messages</h2>

<p>Some content text, blabla.</p>

<p>Some content text, blabla.</p>

<p>Click on the \"x\" symbol to close the callout message.</p>

<div class=\"callout\">

  <span class=\"closebtn\" onclick=\"this.parentElement.style.display=\'none\';\">×</span>

  <div class=\"callout-container\">

    <p>

<!-- <a href=\"#\">

-->

<a class=\"a_tel_2\" href=\"tel:+995598423001\">

<img src=\"../shablon/phone2.gif\" alt=\"მწვანე აფთიაქის ნომერი\" title=\"მწვანე აფთიაქის ნომერი\" width=\"30\" align=\"middle\"/>

<font  size=3 color=black><b>Call Us</b></font>

</a>

<!-- </a> .

-->   

  </p>

  </div>

</div>