.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: linear-gradient(135deg, #4facf7 0%, #007bf3 100%);
  color: #ffffff;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  box-shadow: 0 4px 16px rgba(0, 123, 243, 0.4);
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition:
    opacity 0.3s ease,
    visibility 0.3s ease,
    transform 0.3s ease,
    filter 0.2s ease,
    box-shadow 0.2s ease;
  z-index: 999;
}

.back-to-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  filter: brightness(1.1);
  transform: translateY(-2px);
  box-shadow: 0 6px 22px rgba(0, 123, 243, 0.5);
}

.back-to-top.is-visible:hover {
  transform: translateY(-2px);
}

@media (max-width: 768px) {
  .back-to-top {
    bottom: 20px;
    right: 20px;
    width: 44px;
    height: 44px;
    font-size: 14px;
  }
}