<div id="navigation" style="display:none;">
                    <ul>
                        <li class="selected step-1">
                            <a href="#">Step 1</a>
                        </li>
                        <li class="step-2">
                            <a href="#">Step 2</a>
                        </li>
                        <li class="step-3">
                            <a href="#">Step 3</a>
                        </li>
                        <li class="step-4">
                            <a href="#">Step 4</a>
                        </li>
                        <li class="step-5">
                            <a href="#">Finish</a>
                        </li>

                    </ul>
                </div>

.checked{
    background:transparent url(../images/checked.png) no-repeat top left;
    position:absolute;
    top:0px;
    left:1px;
    width:20px;
    height:20px;
}
.error{
     background:transparent url(../images/error.png) no-repeat top left;
    position:absolute;
    top:0px;
    left:1px;
    width:20px;
    height:20px;
}