JSFiddle - React, Tailwind, and code Playground

HTML

<ul>
<li><a href="#url1">link 1</a></li>
<li><a href="#url2">link 2</a></li>
<li><a href="#url3">link 3</a></li>
<li><a href="#url4">link 4</a></li>
<li><a href="#url5">link 5</a></li>
<li><a href="#url6">link 6</a></li>
<li><a href="#url7">link 7</a></li>
</ul>

CSS

a, a.visited{
    color: #333
}
a:after{
    margin-left: 5px;
    content: url(http://www.thaiseoboard.com/Themes/thaiseoboard_rev2009/images/thai-utf8/new.gif);   
}
a.visited:after{
    content:'';
}

JavaScript

$('a').click(function() {
    localStorage.setItem($(this).attr('href'), true);
    $(this).addClass('visited');
});

$("a").each(function(index, elem){
    if (localStorage.getItem($(elem).attr('href'))){
        $(elem).addClass('visited');
    }
});