[monolithed]

<style type="text/css">

#main {
    background: gray;
    position: relative;
    overflow: hidden;
    width: 100px;
    height: 200px;
}
       
#bottom {    
    background: red;
    margin-top: 100px;
    width: 100px;
    height: 100px;
}
</style>

<div id="main">
     <div id="bottom"></div>      
</div>  

<script type="text/javascript">
window.onload = function(){
     document.getElementById('bottom').style.display = (window.screen.height > 200) ? 'block' : 'none';
};
</script>