/* Container & positioning */
  .whatsapp-fab {
    position: fixed;
    left: 20px;
    bottom: 20px;
    z-index: 9999;
    display: inline-block;
    text-decoration: none;
    -webkit-tap-highlight-color: transparent;
  }

  /* Circle button */
  .whatsapp-btn {
    width: 64px;
    height: 64px;
    border-radius: 50%;
    background: linear-gradient(180deg, #25d366 0%, #128c7e 100%);
    box-shadow:
      0 8px 22px rgba(18,140,126,0.18),
      0 2px 6px rgba(0,0,0,0.12);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: transform 180ms ease, box-shadow 180ms ease;
    border: none;
    outline: none;
  }

  .whatsapp-btn:focus,
  .whatsapp-btn:hover {
    transform: translateY(-4px) scale(1.03);
    box-shadow:
      0 12px 30px rgba(18,140,126,0.22),
      0 4px 10px rgba(0,0,0,0.12);
  }

  /* subtle pulse animation */
  .whatsapp-btn::after {
    content: "";
    position: absolute;
    width: 80px;
    height: 80px;
    border-radius: 50%;
    right: 12px;
    bottom: 12px;
    z-index: -1;
    opacity: 0;
    transform: scale(0.9);
    animation: pulse 2.8s infinite;
    pointer-events: none;
    background: radial-gradient(circle, rgba(37,211,102,0.18) 0%, rgba(18,140,126,0.04) 40%, transparent 60%);
  }

  @keyframes pulse {
    0%   { opacity: 0; transform: scale(0.9); }
    10%  { opacity: 0.32; transform: scale(1.05); }
    60%  { opacity: 0.06; transform: scale(1.25); }
    100% { opacity: 0; transform: scale(1.6); }
  }

  /* SVG styling */
  .whatsapp-icon {
    width: 30px;
    height: 30px;
    display: block;
    fill: white;
  }

  /* small accessible tooltip (screen-reader-friendly but also visible) */
  .whatsapp-tooltip {
    position: absolute;
    right: 82px;
    bottom: 28px;
    background: #111;
    color: #fff;
    padding: 8px 12px;
    border-radius: 8px;
    font-size: 14px;
    white-space: nowrap;
    box-shadow: 0 6px 18px rgba(0,0,0,0.18);
    opacity: 0;
    transform: translateY(6px);
    transition: opacity 160ms ease, transform 160ms ease;
    pointer-events: none;
  }

  .whatsapp-fab:hover .whatsapp-tooltip,
  .whatsapp-fab:focus-within .whatsapp-tooltip {
    opacity: 1;
    transform: translateY(0);
  }

  /* small-screen tweak */
  @media (max-width:420px) {
    .whatsapp-btn { width:56px; height:56px; }
    .whatsapp-icon { width:26px; height:26px; }
    .whatsapp-tooltip { right: 74px; bottom: 22px; font-size:13px; }
  }