body{
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

.btn{
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translate(-50%, -50%);
  background: rgb(219, 108, 5);
  font-size: 20px;
  color: white;
  padding: 10px 30px;
  cursor: pointer;
}

#popUpBox{
  width: 500px;
  overflow: hidden;
  background: rgb(52,152,219);
  box-shadow: 0 0 10px black;
  border-radius: 10px;
  position: absolute;
  top: 50%;
  left: 50%;  
  transform: translate(-50%, -50%);
  z-index: 9999;
  padding: 10px;
  text-align: center;
  display: none;
}