JSFiddle - React, Tailwind, and code Playground

HTML

<div id="main">
    <div id="top"></div>
    <div id="mid">
        <div class="item"></div>
        <div class="item"></div>
        <div class="item"></div>
        <div class="item"></div>
        <div class="item"></div>
        <div class="item"></div>
    </div>
    <div id="bottom">
    </div>
</div>

CSS

#main {
height: auto;
width: 300px;
background: black;
}
#top {
height: 1px;
width: 300px;
background: yellow;
}
#mid {
height: auto;
width: 300px;
background:green;
}
.item {
height: 20px;
width: 90px;
color: red;
float: left;
margin-left: 2px;
margin-top: 2px;
}
#bottom {
width: 300px;
height: 1px;
background: yellow; 
}