<html>
<head>
<style>
    #target {
        background-color:purple;
        width:25px;
        height:25px;
    }
</style>
<script>
    function clicked() {
        var result = parent.document.getElementById("result");
        result.innerHTML = "Pass!";
    }
</script>
</head>
<body>
    <div id="target" onclick="clicked()"></div>
</body>
</html>