JSFiddle - React, Tailwind, and code Playground

HTML

<form>
    <fieldset>
        <legend>This is the legend.</legend>
        <input type="text" />
    </fieldset>
    <fieldset>
        <legend>This is a very very very very very very very very very very very very very very very very very very very very very long legend.</legend>
        <input type="text" />
    </fieldset>
</form>

CSS

fieldset
{
    margin-left: 40px;
    width: 120px;
}

fieldset::before
{
    margin-left: -40px;
    float: left;
    
    content: "before";
}