<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        .hide{
            display: none;
        }
        .menu {
            height: 48px;
            background-color: #DDDDDD;
            line-height: 48px;
        }
        .item{
            float: left;
            height: 48px;
            line-height: 48px;
            padding: 0 40px;
            /*这里加框线的话会让下一列的内容一居中,*/
            border: 1px solid #47a447;
            cursor:pointer;
        }
        .content{
            width: 700px;
            height: 500px;
            background-color: #1d9ad6;
        }
        .active{
            background-color: red;
            color: black;
        }
    </style>
</head>
<body>
    <div style="width: 700px;height:900px;margin: 0 auto ;background-color: #DDDDDD">
        <div class="menu">
            <div class="item"  q="1">菜单1</div>
            <div class="item"  q="2">菜单1</div>
            <div class="item"  q="3">菜单1</div>
        </div>
        <div class="content">
            <div  b="1">内容1</div>
            <div class="hide" b="2">内容2</div>
            <div class="hide" b="3">内容3</div>
        </div>
    </div>
<script src="jquery.js"></script>
<script>
    $('.item').click(function () {
        $(this).addClass('active').siblings().removeClass('active');
     var n = $(this).attr('q');
//        $('.content ').children("[b='"+n+"']").addClass().removeClass('hide').siblings().addClass('hide')
//        $("[b='"+n+"']").addClass().removeClass('hide').siblings().addClass('hide');
        $('.content').children().eq($(this).index()).removeClass('hide').siblings().addClass('hide');
    })
</script>
</body>
</html>