JSFiddle - React, Tailwind, and code Playground

HTML

<span class="fraction">1/2</span>
<span class="fraction">3/4</span>
<span class="fraction">1/32</span>
<span class="fraction">77/102</span>

CSS

.fraction, .top, .bottom {
    padding: 0 5px;    
}

.fraction {
    display: inline-block;
    text-align: center;    
}

.bottom{
    border-top: 1px solid #000;
    display: block;
}

JavaScript

$('.fraction').each(function(key, value) {
    $this = $(this)
    var split = $this.html().split("/")
    if( split.length == 2 ){
        $this.html('<span class="top">'+split[0]+'</span><span class="bottom">'+split[1]+'</span>')
    }    
});