JSFiddle - React, Tailwind, and code Playground

HTML

<div class="vline">
    <div class="hline">
        <div class="box">
            123
        </div>
    </div>
</div>

CSS

body {padding: 8px;}
        
        .box {
            padding: 10px;
            background:#f0f0f0;
        }

        .vline {
            border: solid #666;
            border-width: 1px 0;
            margin: 15px 0;
        }

        .hline {
            border: solid #666;
            border-width: 0 1px;
            margin: -15px 15px;
            padding: 15px 0;
        }