You'll need JavaScript
or for an easier approach a JavaScript library like jQuery.
The basic approach is to add data-* attributes and classes to your elements:
<button class="langButton" data-language="en">EN ARTICLES</button>
<button class="langButton" data-language="de">DE ARTICLES</button>
<button class="langButton" data-language="it">IT ARTICLES</button>
<div class="article en">En 1...</div>
<div class="article en">En 2...</div>
<div class="article de">De 1...</div>
<div class="article de">De 2...</div>
<div class="article it">It 1...</div>
<div class="article it">It 2...</div>
than your jQuery might look like:
$(function() { // Document is now ready to be manipulated
// Cache all .article elements
var $articles = $('.article');
$(".langButton").click(function(){
// Get the "en", "de" or "it" value
var language = $(this).attr("data-language");
// Hide all articles
$articles.hide();
// Show only the ones that have the ."language" related class
$("."+ language ).show();
});
});
Here's a live jsBin example you can play with or even download