css 高度自动过渡三种方法（max-height、transform: scaleY()、grid-template-rows: 0fr）

方法一：使用max-height

<div class="dropdown">             <div class="dropdown-toggle">hover me</div>             <div class="dropdown-menu">               <div class="content">                 <ul>                   <li>Lorem, ipsum dolor.</li>                   <li>Aut, ab facere.</li>                   <li>Sint, assumenda reprehenderit!</li>                   <li>Facilis, ipsa dolore!</li>                   <li>Quae, nam provident!</li>                   <li>Laborum, neque eligendi!</li>                   <li>Ad, quas quo.</li>                   <li>Vitae, facilis similique.</li>                 </ul>               </div>             </div>           </div>