.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background-color: #003366;
  color: white;
  border: none;
  cursor: pointer;
  font-size: 24px;
  display: none; /* Скрыта по умолчанию */
  align-items: center;
  justify-content: center;
  box-shadow: 0 2px 5px rgba(0,0,0,0.3);
  transition: all 0.3s ease;
  z-index: 999;
}

.back-to-top:hover {
  background-color: #003366;
  transform: translateY(-3px);
}

.back-to-top:active {
  transform: translateY(1px);
}