Increase font
HTML
<p>
Some text here
</p>
<div class="increase">Click to increase size.</div>
CSS
.increase {
display: block;
padding: 5px;
background: mediumSeaGreen;
width: 150px;
}
p {
font-size: 12px;
}
JavaScript
$('.increase').on('click', function() {
var fontSize = parseInt($("p").css("font-size"));
fontSize = fontSize + 1 + "px";
$("p").css({'font-size':fontSize});
});