.optimal_box {
	overflow: hidden;
	clear: both;
	padding: 50px 0;
	margin: 0 auto;
}
.optimal_box li {
	width: 28.333%;
	margin: 1% 2.5%;
	float: left;
}
.optimal_box li a {
	position: relative;
	display: block;
	background: #555;
	overflow: hidden;
	clear: both;
	/* -webkit-filter: grayscale(100%);
	-moz-filter: grayscale(100%);
	-ms-filter: grayscale(100%);
	-o-filter: grayscale(100%);
	filter: grayscale(100%); */
}
.optimal_box li a:hover {
	-webkit-filter: grayscale(0);
	-moz-filter: grayscale(0);
	-ms-filter: grayscale(0);
	-o-filter: grayscale(0);
	filter: grayscale(0);
}
.optimal_box li:first-child a {
	background: url("/images/top/3point1.jpg") center center;
	background-size: cover;
}
.optimal_box li:nth-child(2) a {
	background: url("/images/top/3point2.jpg") center center;
	background-size: cover;
}
.optimal_box li:nth-child(3) a {
	background: url("/images/top/3point3.jpg") center center;
	background-size: cover;
}
.optimal_box .op_title {
	position: relative;
	padding: 40px 0;
	width: 80%;
	font-size: 2.6rem;
	line-height: 1.4;
	margin: 140px auto;
	font-family: "游明朝体", "Yu Mincho", YuMincho, "ヒラギノ明朝 Pro", "Hiragino Mincho Pro", "MS P明朝", "MS PMincho",sans-serif;
    font-weight: bold;
	background: rgb(255,255,255,0.8);
	box-shadow: 0px 0px 16px -6px rgba(0,0,0,0.3);
}
h3.copy {
	font-size: 22px !important;
}



@media screen and (max-width: 768px) {
	.optimal_box {
		padding: 0;
	}
	.optimal_box li {
		width: 100%;
		margin: 5% 0;
		float: none;
	}
	.optimal_box .op_title {
		padding: 30px 0;
		width: 70%;
		font-size: 2rem;
		margin:30px auto;