              margin-top: -1in;
            }
            #div2, #div4
            {
                float: right;
                height: 1in;
                width: 1in;
            }
        </style>
    </head>
    <body>
        <p>Test passes if there is <strong>no red</strong>.</p>
        <div id="div1">
            <div id="div2"></div>
            <div id="div3"></div>
            <div id="div4"></div>
        </div>
    </body>
</html>