CSS Animations求助：实现菜单与搜索栏的ease-in-out显隐动画

问题说明 #

已完成汉堡菜单组件，点击汉堡菜单显示链接列表，需实现：

• 菜单显示时以ease-in/slide-in动画呈现
• 菜单隐藏时以ease-out/slide-out动画消失
• 点击「DISCOVER」链接弹出的搜索栏实现相同的显隐动画效果

以下是修改后的完整代码：

HTML（结构无需调整） #

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>Trying Animations out</title>
  <link rel="stylesheet" href="style.css">
</head>

<body>
  <div class="menu-btn">
    <div class="menu-btn__burger"></div>
  </div>
  <ul class="menu">
    <div class="menu-links">
      <li class="menu__item"><a href="#about">NIKE</a></li>
      <li class="menu__item"><a href="#services">NEW BALLANCE</a></li>
      <li class="menu__item"><a href="#contact">REEBOK</a></li>
      <li class="menu__item"><a href="#contact">ADIDAS</a></li>
      <li class="menu__item"><a href="#contact">ASICS</a></li>
    </div>
  </ul>

  <div class="navShowed">
    <h3 class="menuItem discover-link">DISCOVER</h3>
  </div>
  <div class="searchbar">
    <input type="text" placeholder="Search...">
  </div>
  <script src="main.js"></script>
</body>

</html>

CSS（核心动画逻辑修改） #

@font-face {
  font-family: 'Montserrat-Light';
  src: url(fonts\Montserrat-Light.ttf) format(ttf);
}

body {
  background: #272727;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 10vh;
}

ul {
  list-style: none;
}

.menu-btn {
  position: absolute;
  left: 20px;
  display: flex;
  justify-content: center;
  align-items: center;
  width: 40px;
  height: 40px;
  cursor: pointer;
  transition: all .5s ease-in-out;
}

.menu-btn__burger {
  width: 30px;
  height: 4px;
  background: #fff;
  border-radius: 5px;
  box-shadow: 0 2px 5px rgba(255, 101, 47, .2);
  transition: all .5s ease-in-out;
}

.menu-btn__burger::before,
.menu-btn__burger::after {
  content: '';
  position: absolute;
  width: 30px;
  height: 4px;
  background: #fff;
  border-radius: 5px;
  box-shadow: 0 2px 5px rgba(255, 101, 47, .2);
  transition: all .5s ease-in-out;
}

.menu-btn__burger::before {
  transform: translateY(-6px);
}

.menu-btn__burger::after {
  transform: translateY(6px);
}

/* 汉堡按钮动画 */
.menu-btn.open .menu-btn__burger {
  transform: translateX(-32px);
  background: transparent;
  box-shadow: none;
}

.menu-btn.open .menu-btn__burger::before {
  transform: rotate(45deg) translate(35px, -35px);
}

.menu-btn.open .menu-btn__burger::after {
  transform: rotate(-45deg) translate(35px, 35px);
}

/* 汉堡菜单动画修改 */
.menu {
  /* 替换display:none，用transform+opacity实现可过渡的隐藏 */
  transform: translateX(-100%);
  opacity: 0;
  visibility: hidden;
  transition: all 0.5s ease-in-out;
  position: absolute;
  left: 60px;
  top: 10px;
}

.menu-btn.open+.menu {
  transform: translateX(0);
  opacity: 1;
  visibility: visible;
}

.menu-links {
  position: relative;
  left: 0;
  top: 3px;
}

.menu-links a {
  text-decoration: none;
  font: 12px Montserrat-Light, sans-serif;
  color: lightgray;
}

.menu__item {
  display: inline-block;
  margin-right: 10px;
}

.navShowed {
  position: absolute;
  display: flex;
  width: 280px;
  right: 10px;
  margin-top: auto;
}

.menuItem {
  font: 12px Montserrat-Light, sans-serif;
  display: inline-block;
  margin-right: 20px;
  cursor: pointer;
  color: lightgray;
}

.discover-link {
  position: relative;
}

/* 搜索栏动画修改 */
.searchbar {
  /* 替换display:none，用transform+opacity实现可过渡的隐藏 */
  transform: translateY(-100%);
  opacity: 0;
  visibility: hidden;
  position: relative;
  right: 300px;
  top: 38%;
  width: 200px;
  height: 15px;
  transition: all 0.5s ease-in-out;
}

.searchbar input[type="text"] {
  width: 100%;
  height: 100%;
  padding: 0 20px;
  font-size: 10px;
  color: #333;
}

.searchbar.open {
  transform: translateY(0);
  opacity: 1;
  visibility: visible;
}

JavaScript（简化逻辑） #

const menuBtn = document.querySelector('.menu-btn');
const menu = document.querySelector('.menu');
let menuOpen = false;

menuBtn.addEventListener('click', () => {
  menuBtn.classList.toggle('open');
  menu.classList.toggle('open');
  menuOpen = !menuOpen;
});

const discoverLink = document.querySelector('.menuItem:first-child');
const searchbar = document.querySelector('.searchbar');
let searchOpen = false;

discoverLink.addEventListener('click', () => {
  searchbar.classList.toggle('open');
  searchOpen = !searchOpen;
});

关键修改点 #

• 移除display: none/block切换：该属性无法触发CSS过渡动画，改用transform（位移）+opacity（透明度）+visibility（可见性）组合实现显隐
• 统一动画配置：使用0.5s时长的ease-in-out过渡函数，实现自然的缓动效果
• 方向自定义：汉堡菜单采用横向滑入（translateX），搜索栏采用纵向滑入（translateY），可根据需求调整位移方向

内容的提问来源于stack exchange，提问作者user20823821