当用户在弹出窗口之外单击时使弹出窗口关闭

document.addEventListener('click', function(event) {
  var popupWindow = document.getElementById('popupWindow'); // 弹出窗口的DOM元素
  if (event.target !== popupWindow && !popupWindow.contains(event.target)) {
    popupWindow.style.display = 'none'; // 关闭弹出窗口
  }
});

<div class="popup-window">
  <div class="content">
    <!-- 弹出窗口内容 -->
  </div>
</div>

.popup-window {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.5); /* 设置透明背景 */
}

.popup-window .content {
  /* 弹出窗口的样式 */
}

var popupWindow = document.querySelector('.popup-window'); // 弹出窗口的DOM元素

popupWindow.addEventListener('click', function(event) {
  if (event.target === this) {
    this.style.display = 'none'; // 关闭弹出窗口
  }
});