中间栏要放到文档流前面，保证先行渲染。
解法一：margin负值法
左右两栏均左浮动并采用负值margin，中间栏被一个宽度为100%且浮动的元素包含，中间栏设置margin值，类似于双飞翼布局，中间栏不变，将内容部分为两边腾开位置
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta http-equiv="X-UA-Compatible" content="ie=edge" />
<title>margin负值法</title>
<style>
#container {
float: left;
width: 100%;
height: 100px;
background-color: aquamarine;
}
#center {
margin: 0 200px;
}
#left {
float: left;
margin-left: -100%;
width: 200px;
height: 100px;
background-color: cornflowerblue;
}
#right {
float: left;
margin-left: -200px;
width: 200px;
height: 100px;
background-color: violet;
}
</style>
</head>
<body>
<div id="container">
<div id="center"></div>
</div>
<div id="left"></div>
<div id="right"></div>
</body>
</html>
解法二： 绝对定位法
左右两栏采用绝对定位，中间栏通过margin撑开左右间距
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta http-equiv="X-UA-Compatible" content="ie=edge" />
<title>绝对定位法</title>
<style>
* {
margin: 0;
padding: 0;
}
#center {
margin: 0 200px;
width: 100%;
height: 100px;
background-color: green;
}
#left {
position: absolute;
top: 0;
left: 0;
width: 200px;
height: 100px;
background-color: cornflowerblue;
}
#right {
position: absolute;
top: 0;
right: 0;
width: 200px;
height: 100px;
background-color: violet;
}
</style>
</head>
<body>
<div style="position: relative;">
<div id="center"></div>
<div id="left"></div>
<div id="right"></div>
</div>
</body>
</html>
解法三： flex布局
通过flex布局，中间栏设flex:1
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta http-equiv="X-UA-Compatible" content="ie=edge" />
<title>flex法</title>
<style>
* {
margin: 0;
padding: 0;
}
#container {
display: flex;
}
#center {
flex: 1;
width: 100%;
height: 100px;
background-color: #00c9a7;
}
#left {
width: 200px;
height: 100px;
background-color: #e9f3ec;
}
#right {
width: 200px;
height: 100px;
background-color: #608e6f;
}
</style>
</head>
<body>
<div id="container">
<div id="left"></div>
<div id="center"></div>
<div id="right"></div>
</div>
</body>
</html>
解法四：左右浮动法
将左右两栏分别左右浮动，中间栏用margin撑开间距，注意中间栏需要放在最下面。
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta http-equiv="X-UA-Compatible" content="ie=edge" />
<title>左右浮动法</title>
<style>
#center {
margin: 0 200px;
height: 100px;
background-color: #00c9a7;
}
#left {
float: left;
width: 200px;
height: 100px;
background-color: #e9f3ec;
}
#right {
float: right;
width: 200px;
height: 100px;
background-color: #608e6f;
}
</style>
</head>
<body>
<div id="left"></div>
<div id="right"></div>
<div id="center"></div>
</body>
</html>
解法五： grid布局
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta http-equiv="X-UA-Compatible" content="ie=edge" />
<title>grid布局法</title>
<style>
#container {
display: grid;
width: 100%;
grid-template-columns: 200px auto 200px;
}
#center {
width: 100%;
height: 100px;
background-color: #ffaec1;
}
#left {
width: 200px;
height: 100px;
background-color: #ffb7a6;
}
#right {
width: 200px;
height: 100px;
background-color: #ffacd6;
}
</style>
</head>
<body>
<div id="container">
<div id="left"></div>
<div id="center"></div>
<div id="right"></div>
</div>
</body>
</html>
