效果

代码
<!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>flexlayout</title>
<style type="text/css">
* {
margin: 0;
padding: 0;
}
body {
display: flex;
flex-direction: column;
min-height: 100vh;
}
.container {
flex: 1;
display: flex;
}
footer {
height: 40px;
background: #dddddd;
}
nav, aside {
width: 200px;
min-width: 200px;
max-width: 200px;
height: auto;
background: yellowgreen;
}
main {
flex: 1;
background: red;
}
@media (max-width: 1000px) {
aside {
display: none;
}
}
@media (max-width: 768px) {
.container {
flex-direction: column;
}
nav, aside {
width: 100%;
min-width: 100%;
max-width: 100%;
}
main {
height: 90vh;
}
}
</style>
</head>
<body>
<div class="container">
<nav>
<div>
<a href="#">link1</a>
</div>
</nav>
<main>
<div class="block1">
this is block1
</div>
<div class="block2">
this is block2
</div>
</main>
<aside>
<div class="side1">side1</div>
<div class="side2">side2</div>
</aside>
</div>
<footer>
copyrigtht C <a href="#">xuan</a>
</footer>
</body>
</html>