Flex模型的属性介绍

此文记录一下flex布局相关的属性，具体的概念就不介绍了

基础的Html和Css

<!DOCTYPE html>
<html lang="">

<head>
    <meta charset="utf-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width,initial-scale=1.0">
    <title>flex layout</title>
    <style type="text/css">
        @import url('./base.css');
    </style>
</head>

<body>
    <div class="box">
        <div class="item item1">Item1</div>
        <div class="item item2">Item2</div>
        <div class="item item3">Item3</div>
    </div>
</body>
</html>

html,
body {
    margin: 0;
    padding: 0;
}

.box {
    height: 300px;
    width: 400px;
    background-color: yellow;
    color: white;
}

.item {
    width: 100px;
    height: 100px;
    text-align: center;
    line-height: 100px;
}

.item1 {
    background-color: red;
}

.item2 {
    background-color: blue;
}

.item3 {
    background-color: green;
}