<!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>Document</title>
</head>
<style>
div{
background:red;
border:1px solid white
}
#up{
position:absolute;
top:0%;
width: 100vw;
height: 50vh;
background:pink;
}
#bottom{
position:absolute;
bottom: 0%;
width: 100vw;
height: 50vh;
display: flex;
}
#bottom #left{
flex: 1;
background:yellow;
}
#bottom #right{
flex: 1;
background:orange;
}
</style>
<body>
<div id="up">
</div>
<div id="bottom">
<div id="left"></div>
<div id="right"></div>
</div>
</body>
</html>
