How to give a div oval shape?

Question

I tried a lot on oval shape which have cut in both sides but not able to do it please

I need code for oval shape with cut in both side..

Here's my code below:-

.demo{
    width: 100%;
    height: 600px;
    background: white;
    -moz-border-radius: 100px / 50px;
    -webkit-border-radius: 100px / 178px;
    border-radius: 694px / 208px;

    z-index: 100;
    position: relative;
    }

Answer 1

Is this OK ?

HTML

<div id="oval_parent">
    <div id="oval"></div>
</div>

CSS

#oval_parent{
    background:black;
    width:200px;
    height:120px;
    overflow:hidden;
}

#oval{
    width: 220px;
    height: 100px;
    margin:10px 0 0 -10px;  
    background: white;
    -moz-border-radius: 100px / 50px;
    -webkit-border-radius: 100px / 50px;
    border-radius: 100px / 50px;
}

DEMO.