.box{
  	width:500px;	
  	border-radius:5px;
  	margin:0 auto;
  	height:80px;
    line-height:80px; 
    margin-bottom:30px; 
    padding-left:2em;
    background:#ddd; 
    position:relative; 
}
.nav{
    width:0; 
    height:0; 
    font-size:0; 
    border-width:15px; 
    border-style:solid; 
    border-color:transparent #ddd 		transparent transparent; 
    position:absolute; 
    left:-30px; 
    bottom:25px;
  	
}