JSFiddle - React, Tailwind, and code Playground

HTML

<div class="c1">
    <div class="c2">
        1
    </div>
    2
</div>

CSS

.c1 {
    background: red;
    width: 100%;
    
}
.c1 {
    background: blue;
    width: auto;
    display: inline-block;
}