body {
	text-align: left;
	width: 750px;
	margin-right: auto;
	margin-left: auto;
	line-height: 2.5em;
}

.nav{
	margin:19px 0;
	text-align:center;
	clear:both
}
.nav a {
	margin: 20px 5px 20px 5px;
	padding: 10px;
	background-color: #8080c0;
	color: #fff;
	border-radius: 7px;
	-webkit-border-radius: 7px; /* Safari,Google Chrome用 */
	-moz-border-radius: 7px; /* Firefox用 */
	text-decoration: none;
}