/* ── Back to top ────────────────────────────────────────────── */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--color-primary);
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transform: translateY(12px);
  transition: opacity 0.3s ease, transform 0.3s ease, background var(--transition-base);
  z-index: 999;
}

.back-to-top svg {
  width: 20px;
  height: 20px;
  stroke: #fff;
}

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

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

@media (max-width: 480px) {
  .back-to-top {
    display: none;
  }
}