.whatsapp-float {
  position: fixed;
  right: max(18px, env(safe-area-inset-right));
  bottom: max(18px, env(safe-area-inset-bottom));
  z-index: 1000;
  display: grid;
  place-items: center;
  width: 58px;
  height: 58px;
  border-radius: 50%;
  background: #25d366;
  box-shadow: 0 8px 24px rgba(16, 45, 27, .25);
  transition: background-color .2s ease, transform .2s ease;
}

.whatsapp-float:hover {
  background: #1ebe5b;
  transform: translateY(-2px);
}

.whatsapp-float:focus-visible {
  outline: 3px solid #351251;
  outline-offset: 4px;
}

.whatsapp-float img {
  width: 30px;
  height: 30px;
  filter: brightness(0) invert(1);
}

@media (max-width: 640px) {
  .whatsapp-float {
    width: 54px;
    height: 54px;
  }
  .whatsapp-float img {
    width: 28px;
    height: 28px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .whatsapp-float { transition: none; }
}