tableGroup.html

<!DOCTYPE html>
<html>
<head>
    <title>CSS</title>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
    <link rel="stylesheet" type="text/css" href="./style/reset.css" />
    <link rel="stylesheet" type="text/css" href="./style/main.css" />
    <link rel="stylesheet" type="text/css" href="./style/tableGroup.css" />
</head>
<body>
<div class="table border bw3 bc0 bold">
    <div class="bottom">
        <div class="border bw6 bc1">div1</div>
    </div>
    <div class="top">
        <div class="table border-box border bw3 bc2">
            <div class="border bw3 bc1">div2</div>
            <div class="bottom">
                <div class="border bw3 bc1">div3</div>
            </div>
            <div class="border bw3 bc1">div4</div>
            <div class="top">
                <div class="border bw3 bc1">div5</div>
            </div>
        </div>
    </div>
    <div class="border bw6 bc1">div6</div>
    <div class="border bw6 bc1">div7</div>
</div>
</body>
</html>