/* Back to Top Button */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  background: var(--color-accent);
  color: var(--color-text-on-accent);
  width: 50px;
  height: 50px;
  border-radius: 50%;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease, visibility 0.3s ease, transform 0.3s ease;
  z-index: 9999;
  box-shadow: var(--shadow-lg);
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

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

.back-to-top:focus-visible {
  outline: 3px solid var(--color-text-primary);
  outline-offset: 2px;
}

.back-to-top span {
  display: block;
  line-height: 1;
}

@media (max-width: 768px) {
  .back-to-top {
    width: 45px;
    height: 45px;
    bottom: 20px;
    right: 20px;
    font-size: 1.1rem;
  }
}