<html>
<head>
<style>
#main {
width: 350px;
height: 100px;
border: 1px solid #c3c3c3;
display: flex;
}
#main div {
flex-grow: 0;
flex-shrink: 0;
flex-basis: 40px;
}
#main div:nth-of-type(2) {flex-basis: 80px;}
</style>
</head>
<body>
<div id="main">
<div style="background-color:coral;"></div>
<div style="background-color:lightblue;"></div>
<div style="background-color:khaki;"></div>
<div style="background-color:pink;"></div>
<div style="background-color:lightgrey;"></div>
</div>
<p><b>注意：</b>Internet Explorer 和 Safari 不支持 flex-basis 属性。</p>
</body>
</html>