#context {
 width: 978px;
 height: 410px;
 position: absolute;
 top: 50%;
 left: 50%;
 margin: -287px 0 0 -489px;
}

#box_down {
 height: 215px;
 width: 978px;
 position: absolute;
 top: 50%;
 left: 50%;
 margin: 128px 0 0 -489px;
 padding: 0;
 background-color: transparent;
}

#box_down li{
 display: inline;
 height: 215px;
 width: 242px;
}

#box_down img {
	margin: 0 -2px 0 -1px;
	border-top: 20px solid black;
	border-bottom: 20px solid black;
	border-left: 20px solid black;
	border-right: 19px solid black;
}