JSFiddle - React, Tailwind, and code Playground

HTML

<fieldset>
    <legend>Item 1</legend>
    <div class="tab" data-tab="001">Formato 1</div>
    <div class="tab" data-tab="002">Formato 2</div>
    <div class="tab" data-tab="003">Formato 3</div>
    <div class="tab" data-tab="004">Formato 4</div>
    <div class="tab" data-tab="005">Formato 5</div>
    <div class="atb" data-tab="006">Formato 6</div>
    
    <div class="content hide" data-tab="001">Conteudo oculto 1</div>
    <div class="content hide" data-tab="002">Conteudo oculto 2</div>
    <div class="content hide" data-tab="003">Conteudo oculto 3</div>
    <div class="content hide" data-tab="004">Conteudo oculto 4</div>
    <div class="content hide" data-tab="005">Conteudo oculto 5</div>
    <div class="content hide" data-tab="006">Conteudo oculto 6</div>
</fieldset>
<fieldset>
    <legend>Item 2</legend>
    <div class="tab" data-tab="001">Formato 1</div>
    <div class="tab" data-tab="002">Formato 2</div>
    <div class="tab" data-tab="003">Formato 3</div>
    <div class="tab" data-tab="004">Formato 4</div>
    <div class="tab" data-tab="005">Formato 5</div>
    <div class="atb" data-tab="006">Formato 6</div>
    
    <div class="content hide" data-tab="001">Conteudo oculto 1</div>
    <div class="content hide" data-tab="002">Conteudo oculto 2</div>
    <div class="content hide" data-tab="003">Conteudo oculto 3</div>
    <div class="content hide" data-tab="004">Conteudo oculto 4</div>
    <div class="content hide" data-tab="005">Conteudo oculto 5</div>
    <div class="content hide" data-tab="006">Conteudo oculto 6</div>
</fieldset>
<fieldset>
    <legend>Item 3</legend>
    <div class="tab" data-tab="001">Formato 1</div>
    <div class="tab" data-tab="002">Formato 2</div>
    <div class="tab" data-tab="003">Formato 3</div>
    <div class="tab" data-tab="004">Formato 4</div>
    <div class="tab" data-tab="005">Formato 5</div>
    <div class="atb" data-tab="006">Formato 6</div>
    
    <div class="content hide" data-tab="001">Conteudo oculto 1</div>
    <div...

CSS

.focus {
    color: blue;
}

.hide {
    display: none;
}

JavaScript

var todasTabs = document.getElementsByClassName('tab');

function onTabClick () {
    var tab = this;
    var tabs = tab.parentNode.getElementsByClassName('tab');
    var contents = tab.parentNode.getElementsByClassName('content');
    
    for (var i = 0; i < tabs.length; i++) {
        if (tab.dataset.tab == tabs[i].dataset.tab) {
            tabs[i].classList.add('focus');
        } else {
            tabs[i].classList.remove('focus');
        }
    }
    
    for (var i = 0; i < contents.length; i++) {
        if (tab.dataset.tab == contents[i].dataset.tab) {
            contents[i].classList.remove('hide');
        } else {
            contents[i].classList.add('hide');
        }
    }
};

for (var i = 0; i < todasTabs.length; i++) {
    todasTabs[i].onclick = onTabClick;
}