JSFiddle - React, Tailwind, and code Playground

HTML

<fieldset>
    <legend>Fieldset Title</legend>
    
    <label for="input1">Input 1:</label>
    <span><input type="text" id="input1" name="input1"/></span>
    <label for="input1">Input 2:</label>
    <span><input type="text" id="input2" name="input2"/></span>
    <br/>
    <label for="input1">Input 3:</label>
    <span><input type="text" id="input3" name="input3"/></span>
    <label for="input1">Input 4:</label>
    <span><input type="text" id="input4" name="input4"/></span>
</fieldset>

<fieldset>
    <legend>Fieldset Title</legend>
    
    <label for="input1">Input 5:</label>
    <span><input type="text" id="input5" name="input5"/></span>
    
    <br/>
    <label for="input1">Input 6:</label>
    <span><input type="text" id="input6" name="input6"/></span>
    
</fieldset>

CSS

fieldset {
    padding: 20px 0;
    width: 600px;
    margin: 0;
    border: 0;
}

legend {
    display: block;
    width: 100%;
    background: black;
    color: white;
}

label, span{
    float: left;
    width: 150px;
}

input {
    width: 120px;   
}


br {
    clear: both;   
}