JSFiddle - React, Tailwind, and code Playground

HTML

<div class="c1"><h1>1</h1></div>

<div class="c2"><h1>2</h1></div>

CSS

h1 {
    margin: 30px;
}

div {
    width: 100px;
    height: 100px;
    background: yellow;
}
.c1 {
    border: 0.00833px solid red;
}
.c2 {
    border: 0.00834px solid red;
}