/* Botão voltar ao topo — acima do WhatsApp */
.back-to-top {
  position: fixed;
  z-index: 910;
  right: 28px;
  bottom: 140px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  min-width: 44px;
  min-height: 44px;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: 50%;
  background: var(--white);
  color: var(--teal);
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  pointer-events: none;
  transition:
    opacity 0.25s ease,
    transform 0.25s ease,
    visibility 0.25s ease,
    color 0.2s ease,
    background 0.2s ease,
    border-color 0.2s ease;
}

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

.back-to-top:hover {
  color: var(--terracotta);
  border-color: rgba(226, 118, 98, 0.45);
}

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

.back-to-top svg {
  display: block;
  width: 20px;
  height: 20px;
}

@media (max-width: 768px) {
  .back-to-top {
    right: 16px;
    bottom: 116px;
    width: 44px;
    height: 44px;
  }
}

@media (max-width: 480px) {
  .back-to-top {
    bottom: 100px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .back-to-top {
    transition: opacity 0.01ms, visibility 0.01ms;
  }
}