.whatsapp-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 60px;
  height: 60px;
  background-color: #25D366;
  border-radius: 50%;
  color: white;
  font-size: 24px;
  text-decoration: none;
  border: none;
  cursor: pointer;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  transition: background-color 0.3s ease, transform 0.3s ease, box-shadow 0.3s ease;
  /* 固定在左侧下半段，不随滚动消失 */
  position: fixed;
  bottom: 30px; /* 距离底部30px，可调整 */
  left: 30px; /* 距离左侧30px，可调整 */
  z-index: 9999; /* 确保按钮在最上层，不被遮挡 */
}
.whatsapp-button img {
  width: 32px;
  height: 32px;
}
.whatsapp-button:hover {
  background-color: #1EBE5B;
  transform: translateY(-2px);
  box-shadow: 0 6px 8px rgba(0, 0, 0, 0.15);
}
.whatsapp-button:active {
  background-color: #169F46;
  transform: translateY(0);
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}