div{
height: 650px;
background:#ccc;
/*the magic happens here*/
border-top:42px solid #fff;
}
ul{
top: 0;
width: 100%;
height:20px;
position: fixed;
background: deeppink;
margin:0;
padding:10px;
}
li{
float:left;
list-style:none;
padding-left:10px;
}
div:first-of-type{
margin-top:0;
}