检测div外部的单击并切换菜单

<div id="container">
  <button id="menu-toggle">菜单</button>
  <div id="menu">菜单内容</div>
</div>

#container {
  position: relative;
}

#menu {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
}

#menu-toggle {
  cursor: pointer;
}

var container = document.getElementById("container");
var menuToggle = document.getElementById("menu-toggle");
var menu = document.getElementById("menu");

function handleClickOutside(event) {
  var target = event.target;
  if (target !== container && !container.contains(target)) {
    toggleMenu();
  }
}

function toggleMenu() {
  if (menu.style.display === "none") {
    menu.style.display = "block";
  } else {
    menu.style.display = "none";
  }
}

menuToggle.addEventListener("click", toggleMenu);
document.addEventListener("click", handleClickOutside);