<!doctype html>
<html>
<head>
    <style>
        testcase::before {
            content:"Before";
            display: block;
            background-color: green;
            color: white;
            width: 100px;
            height: 100px;
        }
    </style>
</head>
<body>
    <p>Test the specificity of pseudo elements. If the text succeed, there should be a green rectangle with the text "Before".</p>
    <testcase class="testcase"></testcase>
</body>
</html>