#scrollToTop {
  position: fixed;
  bottom: 40px;
  right: 30px;
  z-index: 999;
  background-color: #5b5a5a;
  color: #fff;
  border: none;
  padding: 12px 16px;
  
  font-size: 20px;
  cursor: pointer;
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.3);
  display: none; /* 처음엔 숨김 */
  transition: opacity 0.3s ease;
}

#scrollToTop:hover {
  background-color: #555;
}