body {
  font-family: Arial, Helvetica, sans-serif;
  font-size: 20px;
}
#myBtn {
display: none;
position: fixed;
bottom: 14px;
right: 20px;
z-index: 99;
font-size: 14px;
border: none;
outline: none;
background-color: blue;
color: white;
cursor: pointer;
  padding: 10px;
border-radius: 10px;
opacity: 0.7;
}
#myBtn:hover {
  background-color: blue;
}