body {
	background: top center/100vw 10vw repeat-y url("./layout/body_background.jpg");
}
article {
	background: top center/100vw 100vw no-repeat url("./layout/visual_background.jpg");
}
article div.contents {
	width: 100vw;
	margin: 0vw auto;
	padding-top: 50vw;
	padding-bottom: 3vw;
}
article div.contents div.box_a,
article div.contents div.box_b {
	width: 80vw;
	padding: 4vw;
	margin: 4vw auto;
	border-radius: 1vw;
}

article {
	width: 100vw;
}

footer {
	width: 100vw;
}