使div像模式一样弹出

<div id="popup" style="display: none;">
  <!-- 弹出内容 -->
</div>

<button onclick="showPopup()">点击弹出</button>

<script>
function showPopup() {
  var popup = document.getElementById("popup");
  popup.style.display = "block";
}
</script>

<div id="overlay" style="display: none;"></div>

<script>
function showPopup() {
  var popup = document.getElementById("popup");
  var overlay = document.getElementById("overlay");
  
  popup.style.display = "block";
  overlay.style.display = "block";
}
</script>

<div id="overlay" onclick="hidePopup()" style="display: none;"></div>

<script>
function hidePopup() {
  var popup = document.getElementById("popup");
  var overlay = document.getElementById("overlay");
  
  popup.style.display = "none";
  overlay.style.display = "none";
}
</script>