h1 {
	text-align: center;
	font-size: 1.5rem;
}
main {
	max-width: var(--max-content-width);
	padding: 0 var(--sp-L);
}
.preface {
	text-align: center;
	font-size: 1.5rem;
}
.two-books-in-one {
	gap: var(--sp-XL);
	display: grid;
	grid-template-columns: repeat(auto-fit, minmax(min(28rem, 100%), 1fr));
}
.two-books-in-one input[type=checkbox] {
	z-index: -1;
	opacity: 0;
	visibility: hidden;
	align-self: center;
}
.two-books-in-one input[type=checkbox]:checked ~ label > img:first-child {
	display: none;
}
.two-books-in-one input[type=checkbox]:not(:checked) ~ label > img:last-child {
	display: none;
}
.two-books-in-one p {
	align-self: center;
}
.order {
	border-radius: .5rem;
	padding: var(--sp-XS) var(--sp-S);
	align-self: center;
	text-decoration: none;
	color: var(--fg-acc1);
	background: var(--bg-acc1);
}
.white-background {
	background: #FFF;
}
footer {
	padding-top: var(--sp-XL);
}
@media (min-width: 45rem) {
	h1 {
		font-size: 3rem;
	}
}