JSFiddle - React, Tailwind, and code Playground

HTML

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<body>
    <div>
        <p>
            <label for="usuario" class="form">Usuario</label>
            <input type="text" id="usuario">
            <label class="error">Campo obligatorio</label>
        </p>
        
        <p>
            <label for="fecha" class="form">Fecha</label>
            <input type="text" id="fecha">
            <label class="error">Formato dd/mm/aaaa</label>
        </p>
        
        <p>
            <label for="comment" class="form">Comentario</label>
            <textarea id="comment" rows="8"></textarea>
            <label class="error">Max. XXX caracteres</label>
        </p>    
        
        <p>
            <label class="form">Sexo</label>
            <input type="radio" id="radio_hombre" name="sexo"/>
            <label for="radio_hombre" class="option">Hombre</label>
            <input type="radio" id="radio_mujer" name="sexo"/>
            <label for="radio_mujer" class="option">Mujer</label>
            <label class="error">Campo obligatorio</label>
        </p> 
    </div>
</body>
</html>

CSS

body{
    margin: 8px;
    font-size: 14px;
    font-family: Lucida Sans Unicode, Lucida Grande, Arial, Helveticam, Verdana;
    color: #444;
}

p{
    padding-top: 20px;
}

input[type=text], textarea{
    padding: 4px 2px; 
    border: 1px solid #aaa;
    background: #fff;
    width: 30%;
    resize: none;
}

label.form{
    font-size: 14px;
    text-align: right;
    width: 15%;
    float: left;
    margin: .3em 2% 0 0;
}

label.option{
    margin-right: 20px;
}

.error{
    font-size: 13px;
    padding: 4px 18px;
    color: #D8000C;
    background-color: #FDD5CE;
    border: 1px solid #D8000C;
    margin: 40px;
}