exercise 3

by CloughyLow

HTML

<div></div>
<button>Click</button

CSS

div {
    width: 100px;
    height: 100px;
    background: red;
    opacity: 0.2;
}

JavaScript

$(document).ready(function() {

    $('button').click(function() {
        $('div').css('opacity','+=0.2');
    });

});