.site-back-to-top {
  position: fixed;
  right: 20px;
  bottom: 20px;
  z-index: 1200;
  border: 1px solid rgba(0, 217, 255, 0.35);
  border-radius: 999px;
  background: rgba(30, 30, 30, 0.9);
  color: #f5f7fa;
  font-size: 0.85rem;
  font-weight: 700;
  line-height: 1;
  padding: 10px 14px;
  cursor: pointer;
  opacity: 0;
  transform: translateY(6px);
  pointer-events: none;
  transition: opacity 0.2s ease, transform 0.2s ease, color 0.2s ease;
}

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

.site-back-to-top:hover,
.site-back-to-top:focus-visible {
  color: #00d9ff;
}

.back-to-top {
  display: none !important;
}

@media (max-width: 640px) {
  .site-back-to-top {
    right: 12px;
    bottom: 12px;
    padding: 10px 12px;
  }
}