Overflow overflow:hidden

HTML

<div id="wrapper">
    <div id="parent">
        <button>I am a button</button>
    </div>
</div>

CSS

#wrapper{
    width:5px;
    height:5px;
    border:1px solid #000;
    overflow:hidden;
}

#parent{
    position:relative;
}

button{
    position:fixed;
    margin:10px 0px 0px 30px;
}