.bd-placeholder-img { font-size: 1.125rem; text-anchor: middle; user-select: none; }

#bookshelf { background: linear-gradient(180deg, #fff 0%, #f7f3ec 100%); min-height: calc(100vh - 150px); }

a.book { display: block; color: inherit; text-decoration: none; }
a.book img {
    border-radius: 2px 4px 4px 2px;
    box-shadow: 0 2px 8px rgba(0,0,0,.25), inset -1px 1px 2px rgba(255,255,255,.5);
    transition: transform .15s ease-out;
}
a.book:hover img { transform: translateY(-2px); }

.big-book img {
    width: 100%;
    border-radius: 2px 4px 4px 2px;
    box-shadow: 0 4px 16px rgba(0,0,0,.35), inset -1px 1px 2px rgba(255,255,255,.5);
}