JSFiddle - React, Tailwind, and code Playground

by Brunno Romero

HTML

<form action="envia.php" method="post" id="form1">
    <input type="text" name="nome" id="nome" class="name" value="Nome" onFocus="if(this.value =='Nome' ) this.value=''" onBlur="if(this.value=='') this.value='Nome'">
    <input type="text" name="email" id="email" class="email" value="Email" onFocus="if(this.value =='Email' ) this.value=''" onBlur="if(this.value=='') this.value='Email'">
    <input type="text" name="ddd" id="ddd" class="ddd" value="DDD" onFocus="if(this.value =='DDD' ) this.value=''" onBlur="if(this.value=='') this.value='DDD'" maxlength="3">
    <input type="text" name="telefone" id="telefone" class="telefone" value="Telefone" onFocus="if(this.value =='Telefone' ) this.value=''" onBlur="if(this.value=='') this.value='Telefone'" maxlength="9">
    <p></p>
    <p><strong>Escolha a Data do Evento:</strong>

    </p>
    <select name="dia" id="dia" class="dia">
        <option selected value="Dia">Dia</option>
        <option value="1">1</option>
        <option value="2">2</option>
        <option value="3">3</option>
        <option value="4">4</option>
        <option value="5">5</option>
        <option value="6">6</option>
        <option value="7">7</option>
        <option value="8">8</option>
        <option value="9">9</option>
        <option value="10">10</option>
        <option value="11">11</option>
        <option value="12">12</option>
        <option value="13">13</option>
        <option value="14">14</option>
        <option value="15">15</option>
        <option value="16">16</option>
        <option value="17">17</option>
        <option value="18">18</option>
        <option value="19">19</option>
        <option value="20">20</option>
        <option value="21">21</option>
        <option value="22">22</option>
        <option value="23">23</option>
        <option value="24">24</option>
        <option value="25">25</option>
        <option value="26">26</option>
        <option value="27">27</option>
        <option...

CSS

.hide {
    display: none;
}

.add {
    animation: fadein 2s;
    -moz-animation: fadein 2s;
    /* Firefox */
    -webkit-animation: fadein 2s;
    /* Safari and Chrome */
    -o-animation: fadein 2s;
    /* Opera */
}

.remove {
    display: none;
}
@keyframes fadein {
    from {
        opacity:0;
    }
    to {
        opacity:1;
    }
}
@-moz-keyframes fadein {
    /* Firefox */
    from {
        opacity:0;
    }
    to {
        opacity:1;
    }
}
@-webkit-keyframes fadein {
    /* Safari and Chrome */
    from {
        opacity:0;
    }
    to {
        opacity:1;
    }
}
@-o-keyframes fadein {
    /* Opera */
    from {
        opacity:0;
    }
    to {
        opacity: 1;
    }
}

JavaScript

var selectTemas = document.getElementById('temas');

selectTemas.addEventListener('change', function () {
    var selected = this.options[this.selectedIndex].dataset.section;
    document.querySelector('div[data-name]').className = 'hide';
    document.querySelector('div[data-name="' + selected + '"]').className = 'add';
});