#scrollTopBtn {
  display: none;
  position: fixed;
  bottom: 80px;
  right: 20px;
  z-index: 999;
  background: #f36400;
  color: #fff;
  font-size: 20px;
  padding: 12px 16px;
  border-radius: 50%;
  cursor: pointer;
  box-shadow: 0 4px 6px rgba(0,0,0,0.3);
  transition: opacity 0.3s, transform 0.3s;
}

#scrollTopBtn:hover {
  background: #d95300;
  transform: scale(1.1);
}