JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
    <ul class="menu openDown">
        <li>Option 1</li>
        <li>Option 2</li>
        <li>Option 3</li>
        <li>Option 4</li>
        <li>Option 5</li>
    </ul>  
</div>

CSS

.container{
    border: 1px solid grey; 
    padding: 10px; 
    height: 900px; 
    width: 350px; 
}

ul.menu{
    list-style: none; 
    padding: 0; 
    margin: 0; 
    border: 1px solid #eee; 
    width: 200px; 
    position: absolute; 
}

ul.menu.openDown{
    
}

ul.menu.openUp{
    bottom: 100%; 
}