.whatsapp-fab {
  position: fixed;
  bottom: calc(1.75rem + env(safe-area-inset-bottom, 0px));
  right: calc(1.75rem + env(safe-area-inset-right, 0px));
  z-index: 900;
  display: flex;
  align-items: center;
  gap: 0.625rem;
  min-height: 56px;
  max-width: calc(100vw - 3.5rem);
  padding: 0.75rem 1.25rem;
  border: 2px solid #fff;
  border-radius: 999px;
  background: #25d366;
  color: #fff;
  box-shadow: 0 4px 16px #0003;
  text-decoration: none;
  transition: background 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;
}

.whatsapp-fab i {
  flex: 0 0 auto;
  font-size: 1.75rem;
  line-height: 1;
}

.whatsapp-fab__label {
  font-size: 0.9375rem;
  font-weight: 700;
  line-height: 1.2;
}

.whatsapp-fab:hover {
  background: #25d366;
  color: #000;
  transform: scale(1.08);
  box-shadow: 0 6px 20px #00000040;
}

.whatsapp-fab:focus-visible {
  outline: 3px solid #111;
  outline-offset: 3px;
  color: #000;
}

.whatsapp-fab:hover .whatsapp-fab__label,
.whatsapp-fab:focus .whatsapp-fab__label {
  color: inherit;
}

.whatsapp-fab:active {
  transform: scale(0.97);
}

@media (max-width: 639px) {
  body {
    padding-bottom: calc(56px + env(safe-area-inset-bottom, 0px));
  }

  .whatsapp-fab {
    right: 0;
    bottom: 0;
    left: 0;
    justify-content: center;
    box-sizing: border-box;
    min-height: calc(56px + env(safe-area-inset-bottom, 0px));
    max-width: none;
    padding: 12px max(1rem, env(safe-area-inset-right, 0px))
      calc(12px + env(safe-area-inset-bottom, 0px))
      max(1rem, env(safe-area-inset-left, 0px));
    border: 0;
    border-radius: 0;
    box-shadow: 0 -2px 12px #0003;
  }

  .whatsapp-fab:hover,
  .whatsapp-fab:active {
    transform: none;
  }

  .whatsapp-fab:focus-visible {
    outline-offset: -3px;
  }
}

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

  .whatsapp-fab:hover,
  .whatsapp-fab:active {
    transform: none;
  }
}