第二周-3：CSS核心技术

（1）神奇的float；

<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Document</title>
    <style type="text/css">
        div{
            height: 100px;
            float: left;
        }
        .container{
            border:1px solid blue;
            height: 300px;
             250px;
            background-color: antiquewhite;
        }
        .first{
            background: red;
        }
        .second{
            background: cyan;
        }
        .third{
            background: chartreuse;
        }
        .n{
            background: darkorchid;
        }
    </style>
</head>
<body>
    <div class="container">
        <div class="first">
            第一个div
        </div>
        <div class="second">
            第二个div
        </div>
        <div class="third">
            第三个div
        </div>
        <div class="n">
            第n个div
        </div>
    </div>
</body>
</html>

（2）定位position；

<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Document</title>
    <style type="text/css">
        div{
            height: 100px;
             100px;
        }
        .rel{
            background: red;
            display: inline-block;
        }
        .abs{
            background: green;
            display: inline-block;
        }
    </style>
</head>
<body>
    <div class="rel"></div>
    <div class="abs"></div>
</body>
</html>