<!DOCTYPE html>
<html>
<head>
<style>
#myBtn {
display: none;
position: fixed;
bottom: 20px;
right: 30px;
z-index: 99;
font-size: 15px;
border: none;
outline: none;
background-color: pink;
color: white;
cursor: pointer;
padding: 15px;
border-radius: 4px;
}

#myBtn:hover {
background-color: #555;
}
</style>