<!DOCTYPE html>
<style>
#absolute {
    position: absolute;
    background-color: chartreuse;
    top: 100px;
    left: 100px;
    width: 200px;
    height: 20px;
}
#fixed {
    background-color: salmon;
    width: 50px;
    height: 20px;
}
#overlap {
    position:absolute;
    background-color: pink;
    top: 0;
    left: 0;
    height: 75px;
    width: 75px;
}
</style>
<div id="overlap"></div>
<div id="absolute">
    <div id="fixed"></div>
</div>