Edit in JSFiddle

Result
JavaScript
HTML
CSS

$(document).ready(function () {
                $("#prevAll").click(function () {
                    $(".css").removeClass("css").prevAll().addClass("css");
                });
            });

<html>
        <head>
            <title>prevAll</title>
        </head>
        <body>
        <div>
        <p>This is paragraph element. This is colored.</p>
        <div>This is div element.</div><br>
        <span class="css">This is span elment.</span><br />
        </div><br />
        <input type="button" id="prevAll" value="prevAll" />
        <input type="button" id="reset" value="Reset" onclick="location.reload()" />
        </body>
        </html>

.css
            {
                color:Aqua;
                font-size:30px;
            }