#wrap {width: 100%;}

header {
	display: flex;
	justify-content: space-between;
	border-bottom: 1px solid #ddd;
	height: 7rem;
}
header .logo {
	display: block;
	width: 85%;
	padding: 1.5rem 2rem;
}
header .logo img {
	height: 100%;
}
header .back {
	width: 7rem;
	height: 100%;
	display: block;
	background: url("../img/arrow.png") no-repeat center / 1rem;
}