這是我的代碼筆：https://codepen.io/squishyboots19996/pen/BaoQjPL我正在嘗試創(chuàng)建一個(gè)導(dǎo)航菜單，當(dāng)您將鼠標(biāo)懸停在箭頭上時(shí)，該菜單會(huì)滑入，然后當(dāng)鼠標(biāo)離開(kāi)菜單時(shí)會(huì)滑開(kāi)。我有 UIController.showMenu 和 UIController.closeMenu。如果我在控制臺(tái)中調(diào)用其中任何一個(gè)，它們就會(huì)按預(yù)期工作。但是 closeMenu 的事件偵聽(tīng)器不起作用。它只是沒(méi)有檢測(cè)到鼠標(biāo)離開(kāi)菜單并且沒(méi)有關(guān)閉。如果我向函數(shù)添加 console.log("Hello") ，它將在頁(yè)面首次加載時(shí)觸發(fā)。但當(dāng)我需要它時(shí)就不起作用了。應(yīng)用程序.js：var Controller = (function() {    UIController.updateNav;    setInterval(UIController.moveArrowDown, 3000);    //UIController.addBodyMargin(); document.querySelector('#menuArrow').addEventListener("mouseover", UIController.openMenu);      document.querySelector('#sideMenu').addEventListener("onmouseleave", UIController.closeMenu);});//-----------------------------------------------------------var UIController = (function() {    return {        openMenu: (function(){          document.getElementById('sideMenu').style.marginLeft = '0';          document.getElementById('menuArrow').style.marginLeft = '250px';          document.body.style.marginLeft = '25px'        }),        closeMenu: (function(){          document.getElementById('sideMenu').style.marginLeft = '-250px';          document.getElementById('menuArrow').style.marginLeft = '0';          document.body.style.marginLeft = '0';        })        }})();document.addEventListener('DOMContentLoaded', (event) => {  Controller();})導(dǎo)航欄.css：.sidemenu {  height: 100vh;  width: 250px;  position: fixed;  top: 0;  left: 0;  background-color: red;  z-index: 5001;  display: flex;  flex-direction: column;  justify-content: center;  align-items: center;  margin-left: -250px;  transition: .5s;  cursor: pointer;}.sidemenu ul {  list-style: none;  padding: 0;}.sidemenu a {  text-decoration: none;  font-size: 2rem;}.expand-arrow {  z-index: 4999;  position: fixed;  transition: .5s;  bottom: 50%;}