<a href="#">TIKLA</a>
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<span></span>

a{display: inline-block; background: #00FF99; padding:20px; border-bottom:4px solid #00CC00; color:#00CC99; text-decoration:none; margin-bottom:20px;}
span{display:block; font-size:30px; color:red; margin-bottom:20px;}

$("a").click(function(){
  $("span").html("W3TR");
});