.clearfix:after {
	content: '';
	display: block;
	clear: both;
}
.main_visual {
	margin: 0 auto;
	position: relative;
	min-width: 660px;
	overflow: hidden;
}
.slider_container {
	width: 100%;
	overflow: hidden;
}
.slider {
	width: 400%;
	list-style: none; 
}
.slider li {
	width: 25%;
	float: left;
}
.slider > li > a { 
	display: block;
	width: 640px;
	margin: 0 auto;
}

.bg_visual1 {
	background: url("../img/bg01.gif") repeat-x 0;
}
.bg_visual2 {
	background: url("../img/bg01.gif") repeat-x 0;
}
.bg_visual3 {
	background: url("../img/bg01.gif") repeat-x 0;
}
.bg_visual4 {
	background: url("../img/bg01.gif") repeat-x 0;
}