.csb-btn {
  position: fixed;
  bottom: 20px;
  right: 20px;
  background-color: #25D366;    /* WhatsApp green */
  color: white;
  padding: 12px 20px;
  font-size: 16px;
  border-radius: 50px;
  text-decoration: none;
  box-shadow: 0 4px 12px rgba(0,0,0,0.2);
  z-index: 9999;
  display: flex;
  align-items: center;
  transition: transform 0.2s ease;
}
.csb-btn i {
  margin-right: 8px;
}
.csb-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(0,0,0,0.3);
}
@keyframes csb-pulse {
  0%, 100% { box-shadow: 0 0 0 0 rgba(37,211,102, 0.7); }
  50% { box-shadow: 0 0 0 10px rgba(37,211,102, 0); }
}
.csb-pulse {
  animation: csb-pulse 2s infinite;
}