<!DOCTYPE html>
<style>
body {
margin: 0;
}
.container {
position: absolute;
height: 1000px;
background-color: blue;
}
#child {
width: 600px;
}
.overflow {
width: 800px;
height: 50px;
}
</style>
<div class="container">
<div id="child">
<div class="overflow"></div>
</div>
</div>